HomeMy WebLinkAboutApril 11, 2000 Agenda AGENDA
CITY OF DENTON CITY COUNCIL
April 11, 2000
Agendll No.
Agenda Item,,
Date_
After determining that a quorum is present and convening in an Open Meeting, the City Council
will convene in a Closed Meeting of the City of Denton City Council on Tuesday, April 11, 2000
at 5:15 p.m. in the City of Denton Council Work Session Room, Denton City Hall, at 215 East
McKinney, Denton, Texas to consider specific items when these items are listed below under the
Closed Meeting section of this agenda. When items for consideration are not listed under the
Closed Meeting section of the agenda, the City Council will not conduct a Closed Meeting at
5:15 p.m. and will convene at the time listed below for its regular or special called meeting. The
City Council reserves the right to adjourn into a Closed Meeting on any item on its Open
Meeting agenda consistent with Chapter 551 of the Texas Government Code, as amended, as set
forth below.
1. Closed Meeting:
[**Before the Denton City Council may deliberate, vote, or take final action on each of
the agenda items posted as a competitive matter in a Closed Meeting under the provisions
of TEX. GOV'T. CODE Section 551.086(c), the City Council must first make a good
faith determination, by majority vote of its members, that the particular agenda item is a
competitive matter that satisfies the requirements of Section 551.086(b)(3). The vote
shall be taken during the Closed Meeting and shall be included in the certified agenda of
the Closed Meeting. If the City Council fails to determine by a majority vote that the
particular agenda item satisfies the requirements of Section 551.086(b)(3), the City
Council may not deliberate or take any further action on that agenda item in the Closed
Meeting.]
Deliberations Regarding Certain Public Power Utilities: Competitive Matters ---
Under TEX. GOV'T. CODE Section 551.086.** Deliberations Concerning Real
Property --- Under TEX. GOV'T. CODE Section 551.072. Consultation With
Attorney --- Under TEX. GOV'T. CODE Section 551.071.
(1)
Receive information from Staff, discuss, deliberate, consider, and provide
Staff with direction respecting the valuation of, and the possible sale,
transfer, assignment, or other divestiture of real property pertaining to the
City of Denton's electric utility system, including, without limitation: the
Gibbons Creek generation facility located in Grimes County, Texas; the
Spencer generation facility located on Spencer Road in Denton County,
Texas; the two hydroelectric facilities located in Denton County, Texas;
and other components of the City's electric generation assets. Conduct a
consultation with the City's attorneys in order to obtain the advice and
recommendations of the City's attorneys concerning the above-referenced
issues, where to discuss such issues and matters in a public meeting would
conflict with the attorneys' duties and professional responsibilities to their
client under the Texas Disciplinary Rules of Professional Conduct.
B. Consultation with Attorney - Under TEX. GOV'T. CODE Sec. 551.071
Discuss and receive briefing from attorneys on status and possible
settlement of litigation styled Municipal Administrative Services, Inc. v.
City of Denton, Cause No. 99-50263-367 currently pending in the 367th
District Court of Denton County, Texas.
City of Denton City Council Agenda
April 11, 2000
Page 2
ANY FINAL ACTION, DECISION, OR VOTE ON A MATTER DELIBERATED IN A
CLOSED MEETING WILL ONLY BE TAKEN IN AN OPEN MEETING THAT IS HELD IN
COMPLIANCE WITH TEXAS GOVERNMENT CODE, CHAPTER 551, EXCEPT TO THE
EXTENT SUCH FINAL ACTION, DECISION, OR VOTE IS TAKEN IN THE CLOSED
MEETING IN ACCORDANCE WITH THE PROVISIONS OF SECTION 551.086 OF THE
TEXAS GOVERNMENT CODE (THE "PUBLIC POWER EXCEPTION"). THE CITY
COUNCIL RESERVES THE RIGHT TO ADJOURN INTO A CLOSED MEETING OR
EXECUTIVE SESSION AS AUTHORIZED BY TEX. GOV'T. CODE, SECTIONS 551.001,
ET SEQ. (THE TEXAS OPEN MEETINGS ACT) ON ANY ITEM ON ITS OPEN MEETING
AGENDA OR TO RECONVENE IN A CONTINUATION OF THE CLOSED MEETING ON
THE CLOSED MEETING ITEMS NOTED ABOVE, IN ACCORDANCE WITH THE TEXAS
OPEN MEETINGS ACT, INCLUDING, WITHOUT LIMITATION SECTIONS 551.071-
551.086 OF THE TEXAS OPEN MEETINGS ACT.
Work Session of the City of Denton City Council on Tuesday, April 11, 2000 at 6:00 p.m. in the
Council Work Session Room in City Hall, 215 E. McKinney Street, Denton, Texas at which the
following items will be considered:
NOTE: A Work Session is used to explore matters of interest to one or more City Council Members or
the City Manager for the purpose of giving staff direction into whether or not such matters should be
placed on a future regular or special meeting of the Council for citizen input, City Council deliberation
and formal City action. At a Work Session, the City Council generally receives informal and preliminary
reports and information from City staff, officials, members of City committees, and the individual or
organization proposing council action, if invited by City Council or City Manager to participate in the
session. Participation by individuals and members of organizations invited to speak ceases when the
Mayor announces the session is being closed to public input. Although Work Sessions are public
meetings, and citizens have a legal right to attend, they are not public hearings, so citizens are not allowed
to participate in the session unless invited to do so by the Mayor. Any citizen may supply to the City
Council, prior to the beginning of the session, a written report regarding the citizen's opinion on the
matter being explored. Should the Council direct the matter be placed on a regular meeting agenda, the
staff will generally prepare a final report defining the proposed action, which will be made available to all
citizens prior to the regular meeting at which citizen input is sought. The purpose of this procedure is to
allow citizens attending the regular meeting the opportunity to hear the views of their fellow citizens
without having to attend two meetings.
1. Receive a report from Willie Hudspeth regarding tree removal from his property.
Receive a report, hold a discussion, and give staff direction regarding a follow-up report
to the Teasley Lane Corridor Traffic Study.
o
Consider approval of the Preliminary Design Report by Freese & Nichols for the
Modifications to Lake Ray Roberts Surface Water Treatment Plant.
Receive a report, hold a discussion, and give staff direction regarding a resolution of the
City Council of the City of Denton, Texas determining competitive matters re,peering
certain public power utilities which are subject to protection under the Texas Open
Meetings Act and the Texas Public Information Act; adopting declarations and findings
in the preamble; and providing for an effective date.
City of Denton City Council Agenda
April 11, 2O0O
Page 3
Receive a report, hold a discussion, and give staff direction concerning dually certified
service areas between the City of Denton and Argyle Water Supply Corporation.
CERTIFICATE
I certify that the above notice of meeting was posted on the bulletin board at the City Hall of the
City of Denton, Texas, on the day of ~ 2000 at o'clock (a.m.)
(p.m.)
CITY SECRETARY
NOTE: THE CITY OF DENTON CITY COUNCIL WORK SESSION ROOM IS
ACCESSIBLE IN ACCORDANCE WITH THE AMERICANS WITH DISABILITIES ACT.
THE CITY WILL PROVIDE SIGN LANGUAGE iNTERPRETERS FOR THE HEARING
IMPAIRED IF REQUESTED AT LEAST 48 HOURS IN ADVANCE OF THE SCHEDULED
MEETING. PLEASE CALL THE CITY SECRETARY'S OFFICE AT 349-8309 OR USE
TELECOMMUNICATIONS DEVICES FOR THE DEAF (TDD) BY CALLING 1-800-
RELAY-TX SO THAT A SIGN LANGUAGE INTERPRETER CAN BE SCHEDULED
THROUGH THE CITY SECRETARY'S OFFICE.
Agenda IteJfl /
AGENDA INFORMATION SHEET
AGENDA DATE:
DEPARTMENT:
CM:
April 11, 1999
City Manager's Office
Mike Jez, City Manager~
SUBJECT
Receive a report from Willie Hudspeth regarding tree removal from his property.
BACKGROUND
Council has requested staff to place this item on a Work Session to allow Mr. Hudspeth an
opportunity to present his report in full rather than having to attend multiple Council meetings to
present his report under Citizen Reports.
R~e.~ft;[lly submitt?:
Sf~)~i~e~ Wj~lters
Secretary
AGENDA DATE:
DEPARTMENT:
CM/DCM/ACM:
AGENDA INFORMATION SHEET
April 11~, 2000 /
/
Dave Hill, 349-831~~5
A{lenda
Agenda item.,
Dm_
SUBJECT
Receive a report, hold a discussion, and give staff direction regarding a follow-up report to the
Teasley Lane Corridor Traffic Study.
BACKGROUND
This agenda item is the second phase ora three-part study. Two new documents have been prepared for
Council review, a revised Teasley Lane Corridor Traffic Study (Exhibit # 1) and a Level of Service
Evaluation (Exhibit #2). Staffwill present summaries of these reports during the April 11th work session.
The primary focus of the discussion is the issue of transportation concurrency, which is intended to
address the problems and solution options associated with the installation of roadway improvements
concurrent with (or in advance of) the needs generated by new development. The last phase of the study,
tentatively scheduled for May 23rd, 2000, is intended to outline a capital improvements strategy needed to
serve the Teasley Area at an acceptable Level of Service.
During the February 8th, 2000 Council work session, staff presented the Teasley Lane Corridor Traffic
Study, which estimated the roadway capacity needs of Teasley Lane and connecting thoroughfares given
assumed land uses and densities for the study area. The major conclusions of the study indicated that new
travel demand caused primarily by new home construction in Denton and Corinth has nearly exceeded
roadway capacity. The major concem identified by staff was the five to six-year time delay likely to be
encountered in expanding Teasley Lane from two to six lanes. The staff conclusions and options preferred
by City Council following February 8t~ work session discussion are included in Exhibit #3.
Traffic Study Revisions
New elements of the revised Teasley Lane Corridor Traffic Study include:
(1) New traffic counts were taken in March 2000, and Teasley Lane Levels of Service have declined
since February 1999; and
(2) The study assumptions were revised from an assessment of lane needs to a more realistic
assessment of a probable improvements schedule. For example, though Teasley Lane traffic
counts indicate a need for expansion now, the revised study indicates that 2006 is the earliest
time that expansion can reasonably be expected; and
(3)
(4)
The study assumptions have been changed regarding build-out. Only properties with recorded
final plats are assumed to continue building during the period from 2000 to 2006 (when Teasley
Lane is assumed to be expanded to six lanes). The reason for this change was to determine ifa
construction slowdown would yield any concurrency benefits. The effect of the "slowdown
assumption" extends Teasley Area build-out timing from Year 2010 (as originally assumed in
the February 8~h report) to Year 2016. C&P Engineering is now preparing an assessment of
build-out Levels of Services for study area roadways that extends from 2010 to 2016 to
determine if ultimate roadway capacities are adequate to service zoning densities assumed for
the Teasley Area. The 2016 assessment will be handed out to Council at the April 11th work
session; and
The impact of a potential new thoroughfare named the "State School Connector" was assessed to
determine if such a road would provide better traffic circulation to and from 1-35E. In addition,
the potential addition of one or two Community Activity Centers to reduce vehicle trips
currently destined for 1-35E retail services located at the Lillian Miller and Swisher Road
interchanges was assessed.
Traffic Study Conclusions
The March 2000 traffic count data indicates that one section of Teasley Lane, from Lillian Miller to
Robinson, now operates at a Level of Service "F" (LOS "F"). This does not mean that this road segment
operates at LOS F for the entire day. The road segment does operate at LOS "F" for an as yet undetermined
time during either peak morning (7AM to 8AM) and/or evening (4:30 to 6:30 PM) hours. The new traffic
data provides more evidence that travel demand on Teasley continues to increase. If concurrency issues are
not addressed now, the incidence of automobile accidents and related injuries will increase, travel delays will
become more frequent, and motorist frustration problems will worsen.
As indicated previously, the traffic study assumes that between 2000 and 2006 only recorded final plats will
continue with construction projects. This "slowdown assumption" still results in an LOS "F" for all of
Teasley from Lillian Miller to the Denton- Corinth city line, and also results in an LOS "E" for Teasley
from 1-35E to Londonderry.
Policy Issues
Comprehensive Plan- Mobility Plan Relationship
The first and most significant policy issue to be resolved is whether the roadway system that services the
Teasley Area can support traffc at an acceptable Level of Service (LOS). Staff recommends a minimum
LOS "D" for build-out of the area, once all roads have been built to their planned capacity. The "State
School Connector", from Ranchman to State School Road, provides significant benefits to the system, and
should be formally added to the city's Mobility Plan. FM 2499 is currently shown on the Mobility Plan, and
is an important noah-south route that will provide significant relief for FM 2181 (Teasley Lane), even if
only two of the eventual six lanes are constructed by 2010.
ii
The attached traffic study indicates that all roadways segments, if built or expanded according to the
timetable indicated in Table 6, will operate at an LOS "D" or better. However, build-out would not occur
until 2016 because of the "slowdown assumption". The 2010- 2016 traffic study addendum (which will be
completed by April 11th) will provide LOS levels for the completed roadway system at build-out. Until the
addendum is available, staff is unable to arrive at any conclusions regarding the relationship between the
Comprehensive Plan and the Mobility Plan. If the Mobility Plan roadway component cannot accommodate
Comprehensive Plan future land uses and densities, the incompatibilities should be reconciled by amending
one or both of the planning documents, or alternative trip reduction techniques could be considered. The
North Central Texas Council of Governments (NCTCOG) recommends the use of"Travel Demand
Management" (TDM) systems rather than resorting automatically to system capacity expansions.
Concurrency / Capital Improvements Approach
The issue of concurrency is significant, and will have profound impact on short-term property development
within the Teasley Area. If an LOS "D" is used as a minimum standard of acceptability, then Teasley Lane
between Lillian Miller and Robinson no longer operates at an acceptable level. Even more problematic is
the estimated six-year period for expansion of Teasley Lane from two to six lanes. A construction
slowdown or moratorium lasting a very short period of time, such as six to twelve months, might be
considered feasible if needed to make necessary road improvements. Six years, however, is a significant
time interval, and consideration of a slowdown or moratorium lasting six years places Council in a difficult
position.
Staffused a "slowdown assumption" considered to be equitable, given the presumption that once significant
investments in subdivision improVements have been made, it is difficult to envision halting construction
activity. Therefore, recorded plats are considered to be unaffected by any concurrency approach, and
requires consideration of an Interim LOS policy that allows temporary LOS "E" or "F" within specific limits
(see discussion below). The LOS values shown in Table 6 of the traffic study are based upon average daily
traffic; measures of LOS for shorter periods of time are not yet available.
Staff is concemed that the preliminary assessment of the Teasley Area roadway concurrency "gap" is six
years, and every effort should be made to shorten this time period. The real issue is whether a tolerable LOS
can lengthen current system usage, and whether improvements can be made more quickly to shorten the
time taken to expand system capacity. The approach recommended by staff is to develop a concurrency
strategy that is fair to developers and property owners, respects property rights issues, and is related to LOS
objectives that are clearly articulated. At the same time, an aggressive strategy should be developed to
expedite roadway improvements to shorten the gap between travel demand and roadway capacity.
Interim LOS versus Build-Out LOS
Travel demand in the Teasley Area will continue to increase even if new development is stopped entirely,
due to "Base" and "Thru" traffic described in the traffic study. The timeframe involved in achieving needed
roadway improvements spans a period often years, which requires consideration of property rights issues.
These factors raise the policy question of whether an interim LOS policy should be considered, which
expresses a tolerance limit, versus a build-out LOS policy, which expresses a minimum acceptable traffic
standard. Another factor to consider is the disruption in levels of service that will occur once roadway
construction occurs, which will conceivably result in an LOS worse than "D".
Ul
Exhibit #2 describes the recommended approach for addressing this policy issue. Included is the
recommendation that a system be implemented that allows regular monitoring of traffic counts during peak
and non-peak hours. The monitors can then be used to implement appropriate management strategies when
predetermined thresholds have been reached. Staff acknowledges that many variables can affect the actual
traffic patterns that occur, and recommends that tme field data be used as the basis for any land use
regulations that may be considered to address concurrency issues.
OPTIONS
1. Consider the imposition of a short-term moratorium (approximately 3 months) at an upcoming regular
Council meeting until conclusions regarding concurrency and a capital improvements strategy have been
reached.
2. Allow staff the time to meet with developers and property owners in the affected study area, and with
Denton County and TXDOT officials to determine the extent to which a public/private parmership can
be fro,ned to expedite Teasley Lane expansion from two to six lanes.
RECOMENDATION
Staff recommends Option #2. The use of a moratorium is a reactive option, and private developers in the
area should be asked to participate proactively in solutions for the Teasley Area mad improvements.
Potential private funding mechanisms such as assessment districts, public improvements districts, or tax
increment financing districts may be feasible, and are less restrictive. Careful consideration of all
alternatives should occur before a moratorium is imposed.
The City of Denton Mobility Plan should be amended to add the "State School Connector" as shown in the
traffic study. This connector provides an important link to the Teasley Area from State School Road for
northbound motorists that currently use the 1-35E / Lillian Miller intersection to retum to the Teasley Area.
Planning staff should also be instructed to provide an evaluation of potential Community Activity Centers
that could be located centrally within the Teasley Area. The Community Activity Centers provide
substantial benefits; they account for a diversion of 75 percent of the trips that would otherwise be destined
for the 1-35E retail centers located at Lillian Miller and Swisher.
Finally, staffrecommends consideration of the monitoring system that would be installed to take regular
traffic counts to allow evaluation of actual travel demand.
ESTIMATED PROJECT SCHEDULE
Unless instructed otherwise, staff will continue to develop detailed information for a combined concurrency
and capital improvements strategy. A work session has been tentatively scheduled to continue discussion on
these topics on May 23~d. Staff intends to meet with affected developers, Denton County representatives,
and Texas Department of Transportation (TXDOT) officials in the interim.
PRIOR ACTION/REVIEW
The first review of the Teasley Lane Corridor Study occurred on February 8th, 2000.
iv
FISCAL INFORMATION
Financial options will be discussed when the third phase of the Teasley Study is scheduled for Council work
session review.
ATTACHMENTS
Exhibit #1: Revised Teasley Lane Corridor Traffic Study
Exhibit #2: Level of Service Evaluation
Exhibit #3: February 8th, 2000 Council Work Session Summary
Exhibit #4: Teasley Lane Corridor Traffic Study - Land Use Data
Traffic Study and Level of Service Evaluation Prepared By:
C & P Engineering, Ltd.
3501 FM 2181, Suite 230
Corinth, Texas 76205
~Respectfully ~~
~ssistant City Manager, Development Services
V
Exhibit #1
TEASLEY LANE CORRIDOR STUDY
FINAL REPORT
prepared for
CITY OF DENTON
Prepared by
C&P Engineering, Ltd.
3501 F.M. 2181 · Suite 230 ° Corinth, Texas 76205 ° (940)270-0602
TEASLEY LANE CORRIDOR STUDY
CITY OF DENTON
PURPOSE OF STUDY
The purpose &this study is to address the traffic impact of future developments along the Teasley
Lane Corridor during the ten year period of 2000 - 2010. This corridor includes the influence area
affecting two specific street segments: Teasley Lane from IH 35E on the north to the Corinth city
limit on the east; and Lillian Miller from IH 35E on the north to Teasley Lane on the south,
Figure 1 has been developed to depict the influence area that will create the furore traffic impact on
the streets and roads in the Teasley Corridor. This area was identified by the City's Planning
Department in a document entitled "The South Denton Project",
Build out within the study area has been projected to occur by the year 2016. An addendum to this
report is being prepared to determine the level of service for all affected roadways once all study area
properties have been developed. The addendum will be ready by April 11, 2000.
Page 1
THE SOUTH DENTON STUDY AREA
The study area contains approximately 3,207 acres and includes a variety of land uses. Table 1 has
been prepared to ~ the various land uses as well as the assumed density of development for
each use. The table also includes the ITE (Institute of Transportation Engineers) code associated
with each land use. 1TE data willbe ufili?~xt to determine the trip ends calculated to be generated by
the South Denton area.
It should be noted that the land areas presented in Table 1 include approximately 545 acres that are
already built out and occupied. The impact of these 545 acres was accounted for as being part of the
existing traffic patterns in the study area.
The residential land uses in Table 1 account for 93.4% of the total acreage that makes up the South
Denton area: The majority of the residents that will live in this study area will have no nearby work
or shopping destinations, but will be required to travel significant distances to satisfy these needs.
Most of the retail zoning WIll occur in Unicorn Lake which is located in close proximity to IH 35E.
As a result, much of its trip attraction will be from the IH 35 corridor.
TABLE 1
Trip Generation Data
Residential 210 single family homes 8,600 units
(2,768 acres)
Residential 220 multi-family apartments 1,030 units
(69 acres)
Residential 250 retirement community 1,170 units
(157 acres)
Day Care 565 square feet of gross floor area 20,000 s.f.
(2 acres)
General Office 710 square feet of gross floor area 185,130 s.f.
(17 acres)
Commercial 820 square feet of gross floor area 969,210 s.f.
(89 acres) (for retail and light industrial)
Civic Uses N/A acres 85 acres
(85 acres)
Communication N/A towers 1 tower
Tower (20 acres)
Page
STUDY ASSUMPTIONS AND DATA
The completion of this study involved a cooperative effort between the Consultant and the City's staff
in temps of developing appropriate assumptiOns regarding several traffic and land use related issues
in the corridor. Much of this information was developed by the Planning Department and was
included in "The South Denton Project" document.
The key assumptions and data used in this study have been listed below.
Assumptions
All undeveloped agriculturally zoned or unzoned property in the study area is
assumed to be converted to single-family residential development at an average gross
density of 3.5 dwelling units per acre.
The annual population growth rate for the study period is assumed to be about 4
percent per year, corresponding to the Comprehensive Plan population estimates.
Traffic traveling through the study area is assumed to increase at a rate of 4 percent
per year.
Commercially zoned sites were assumed to develop with a floor to area ratio of 0.25
:1.
Two connector streets were assumed to be constructed: an east/west connector to
tie Teasley Lane with State School Road (year 2004); and a north/south connector
to tie Wind River with the east/west connector (year 2004). See Figure 2.
Two 10 acre Community Activity Centers were assumed to be included in the study
area - construction to occur in 2004 with their full impact shown in the 2006 traffic
projections.
Two Centers were selected because it was assumed that two would be needed to
provide an adequate level of retail services to this area. The assumed general location
of the Centers has been shown on Figure 2. This area was selected because of its
central location within the study area and because this location was assumed to be
able to attract retail customers from the entire study area.
For the 2000 - 2006 period building permits were assumed to be issued only for those
developments that have received final plat approval.
Page 4
10.
!1.
12.
Koy Data
1.
For the 2006 - 2010 period the trip generation for three parcels was assumed not to
occur: the Good Samaritan MF-1; the Acme Brick property; and PD-100. The year
2006 was chosen as the break point because it was assumed that 2006 was the
earliest date that Teasley (FM 2181) Lane could be expanded.
The 4% growth in through traffic was assumed to be constant throughout the study
period.
The extension of Hickory Creek from its intersection with Teasley Lane east to
intersect with the future FM 2499 roadway was assumed to be completed by the year
2005. This project will be private developer funded.
FM 2499 was assumed to be constructed by the year 2010.
The absorption rate for the 2006 - 2010 period was assumed as follows: 8% in the
first year; 7% in the second year; 6% in the third year; and 4% thereafter. Based on
these assumed absorption rates, the total build out of the South Denton area was
calculated to occur by the year 2016.
The City's Comprehensive Plan estimates a city-wide population increase of
approximately 33,000 from 1999 through 2008.
City-wide, during 1998 and 1999, single-family building permits were issued at an
average rate of 70 per month, or 840 per year. Multi-family building permits were
issued at an average rate of 42 units per month, or 504 per year. This represents an
annual growth rate of approximately 4 percent per year for the city as a whole.
Page 5
SCHOOL AREAS
Concern has been expressed regarding the impact of school related traffic on the South Denton area
street system - especially as it relates to school related trips that originate in the City of Corinth.
Figure 2 has been prepared to depict the relative locations of the existing and assumed schools that
may influence the South Denton area. Estimates of the level of influence on Denton schools have
suggested the following percentages of Corinth students at schools in the South Denton area.
McMath Middle School 30%
Houston Elementary School 50%
MeNair Elementary School 90%
Vehicular school related traffic from Corinth has a definite impact on Denton streets especially in the
morning commuter peak period. Studies have shown that the peaking characteristics around schools
are different in two ways from peak period conditions that would typically be encountered on the way
to work each morning.
School area peak period traffic volumes are two to three time higher than the
typical peak period volumes on non-school area streets.
The time period during which the school peak period occurs is typically 20
minutes in length while the typical non-school area peak period duration is 60
minutes~
A number of new schools have been planned for construction in the City of Corinth. This is a direct
result of the significant population growth in both Corinth and Denton. These new schools will
certainly relieve the Corinth school related traffic impact on Denton streets. However, the decline
in the Corinth population in Denton schools will be simply replaced by an increase in students from
the South Denton area.
In completing this corridor study we have interpreted this shift in the school populations in the
following manner.
The peak period traffic patterns will show a change from a definitive orientation to
and from the southeast to a more centralized local area pattern.
The overall daily traffic volumes and patterns will not reflect as significant a change
as will the peak periods. This is due to the influence of other major components of
the typical traffic stream: the home to work traffic; the work to home traffic; and the
retail/commercial traffic generated by the projected 10,800 residential units in the
South Denton area.
Page 6
McMATH
MS
HOBSON
H:OU.STON:.
:ES::,::-:.:::.:.
RYAN
I
CREEK
SCHOOL LOCATIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
d
ROBINSON
::~ / ::~ AREA SCHOOLS
HS/ES o~/ FUTURE STREETS
cq
h
TEASLEY (FM2181)
FIGURE 2
8058Fig1
Page 7
EXISTING CONDITIONS
A number of truffle related data collection efforts was undertaken to establish the existing conditions
for this study. These efforts resulted inthe collection of the following information.
The Consultant collected peak hour turning movement counts in November and
December 1998 at eight key intersection locations within and adjacent to the South
Denton area. These locations have been identified in Figure 3 and the count summary
sheets have been included in a separate attachment to this report,
The City collected 24-hour traffic counts in March 2000 at 12 locations in the study
area. Figure 4 has been prepared to depict these daily traffic volumes. This 24-hour
data was recorded by 60 minute periods and the computer print out for each location
has been included in a separate attachment to this report.
Field data with regard to the number of traffic lanes on the major streets in the study
area and the locations of traffic signal installations was collected by the Consultant.
This data has been recorded on Figures 5 and 6.
A license plate survey was conducted in February 1999 for the South Denton area.
In this effort the license plate numbers of all traffic entering and exiting the study area
were recorded during the morning peak period of 6:45 - 8:45 am and during the
afternoon peak period of 4:30 - 6:30 pm.
The purpose of the license plate survey was to collect data that would allow the
Consultant to quantify the amount of "through" traffic in the study area. In other
words, the amount of the traffic that passes through the area - it has no origin or
destination within the area.
This information was determined for traffic entering and exiting the South Denton
study area as follows: along Lillian Miller on the north; along Teasley Lane on the
north; along Ryan Road on the west; along Hickory Creek Road on the west; along
Robinson Road on the east; and along Teasley lane on the south.
The results of the license plate survey have been depicted on Figures C1 - C6 and
Figures D1 - D6 which have been recorded in a separate attachment to this report.
A table has also been included in a following section (Analysis of Traffic Stream
Components) of this report that summarizes the "through" traffic results.
Page 8
HOBSON
RYAN
PEAK HOUR COUNT LOCATIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
J
ROBINSON
TEASLEY (FM2181)
FIGURE 3
,,~,~F.g2
Page 9
3550
HOBSON --
4254
7397
5190
152
572
RYAN
2039
2171
1720
CREEK ~.~
1736
MARCH 2000
24-HOUR TRAFFIC VOLUMES
TEASLEY LANE CORRIDOR !DTUDY
DENTON, TEXAS
2065
1879
LEGEND
8422
ROBINSON
YEAR 2000
24-HR. VOLUME
TEASLEY (FM2181)
FIGURE 4
8058Fig3
Page 10
4D
°4
4D
4D
4U
HOBSONI~2U
4D
TRANSITION AT
BENT OAKS
RYAN
2U
2U
2U
'~?'~O¢~cREEK
2U
TRANSITION AT
CORINTH CITY LIMIT
LEGEND
2U 2 LANE UNDIVIDED
4U 4 LANE UNDIVIDED
4D 4 LANE DIVIDED
6D 6 LANE DIVIDED
ROBINSON
EXISTING STREET SECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
2U
~ 2U
TEASLEY (FM2181)
FIGURE 5
8058Fi~4
Page 11
HOBSON
RYAN
~CREEK
TRAFFIC SIGNAL LOCATIONS
TEA!gLEY LANE CORRIDOR STUDY
DENTON, TEXAS
ROBINSON
LEGEND
EXISTING SIGNALS
FUTURE SIGNALS
TEASLEY (FM2181)
FIGURE 6
8058Fi9 5,
Poge t2
PROGRA~V~ED CAPITAL IMPROVEMENTS
A number of capital improvements are planned for the general study area. These improvement
projects vary as to size and scope as well as to the level of impact they will have on the traffic
volumes and patterns on the existing South Denton area street system. These capital improvement
projects have been listed below along with their scheduled/estimated construction dates.
Wind River Extension... The extension of Wind River from its intersection with
Teasley/Lillian Miller east to intersect with the southbound IH 35E frontage road was
accomplished during 1999.
This project has created an alternative route for area residents that seek to travel
southbound on IH 35E and want to bypass the IH 35E and Loop 288/Lillian Miller
interchange,
IH 35E Ramp Reversals... The existing ramp configuration at IH 35E and Loop
288/Lillian Miller is estimated to be reconstructed by the year 2003.
This improvement should reduce the traffic volumes on both Lillian Miller and
Teasley Lane through the South Denton area, but its most significant impact will be
to improve traffic operations and safety at the interchange itself.
Hickory Creek Expansion... This project will result in the widening of Hickory
Creek Road from a two lane to a four lane cross section. The project will extend
from FM 1830 to FM 2181 and is scheduled to be completed by the year 2002.
This will be a City/County funded project and will provide increased capacity for area
motorists traveling along Hickory Creek between the limits of this project.
FM 2499.:. This project will result in the construction of a major arterial road from
the south over Lake Lewisville that will intersect IH 35E at the State School/Mayhill
Road interchange. This project has been estimated to be constructed by the year
2010.
This project will allow residents east of Teasley Lane an alternative to access IH 35E
other than using the existing route ofTeasley Lane/Lillian Miller.
The City's current Mobility Plan depicts the projected road system including these four projects that
affect the South Denton area.
Page 13
INITIAL SOUTH DENTON AREA GROWTH
In this section of the report we have responded to concerns expressed by City staffthat the initial
traffic growth in the South Denton area may have been quite significant. We determined that the
initial growth that has precipitated the concerns regarding the South Denton area began in 1997. In
order to quantify the initial growth, we obtained the city's 1997 count map and compared that count
data with corresponding count data that was collected in 1998. Table 2 has been prepared to
summarize the results of this comparison.
TABI.E 2
Initial Growth Evaluation
Lillian Miller: 12,672 vpd 14,668 vpd 15.6%
IH 35 - Southridge
[ Teasley: 6,433 vpd 9,923 vpd 54.3%
Londonderry - Hobson
Teasley: 7,983 vpd 9,561 vpd 19.8 %
Hobson - Lillian Miller
Teasley: 3,471 vpd 7,510 vpd 116.4 %
Lillian Miller - Robinson
As can be seen, the traffic growth over the South Denton area was significant - especially on Teasley
Lane south ofLillian 1Vflter. Our assumption for this study was an average annual growth rate of four
percent, but during the 1997 to 1998 period the growth rate averaged approximately 36%.
It should be noted that during 1997 to 1998 there were very few new residemial units completed in
the study area. Most of the new housing did not come on line until late in 1998. As a result, the
average 36% growth in the South Denton area traffic during that time period may be due to
the influence of the Corinth related growth as well as the growth in Denton jobs and retail
sales.
Page 14
TRIP GENERATION AND DISTRIBUTION
Estimated vehicle trip ends to and from the study area were calculated utilizing trip generation rates
and characteristics collected and compiled by the Institute of Transportation Engineers (ITE). Tables
3 and 4 have been prepared to summarize the associated trip generation data and the calculated trips
that are anticipated to be generated by the South Denton study area as depicted in Figure 1.
Table 3 reflects the land use and trip generation data for the development of the Teasley Lane
Conidor study during the six year period of 2000 - 2006. Only those properties that have received
final plat approval but have yet to be developed are included in this table.
TABLE 3
Calculated Trip Ends
Year 2000 - 2006 Period
S.F. Residential 20,432 400 1,201 1,380 776
(2A35 units)
M.F. Residential 0 0 0 0 0
(0 units)
Mobile Home Park 1,106 19 73 80 49
(230 units)
Retirement Community 0 0 0 0 0
(0 units)
Day Care 0 0 0 0 0
(0 s.f.)
General Office 2,038 254 35 47 229
(185,130 s.f.)
General Re~ail 1,402 21 13 59 64
(32,670 s.f.)
ADT = average daily trips; vpd = vehicles per day; vph = vehicles per hour; in = vehicles
entering the site; out = vehicles exiting the site; and s.f. = square feet.
Page 15
Table 4 reflects the land use and trip generation data for the development of the Teasley Lane
Corridor study during the four year period of 2006 - 2010. This four year development period
excludes three properties: Good Samaritan, Acme Brick, and PD-100.
TABLE 4
Calculated Trip Ends
Year 2006 - 2010 Period
S.F. Residential 16,326 320 959 1,103 620
(1,706 units)
M.F. Residential 1,930 24 125 121 60
(291 units)
Mobile Home Park 0 0 0 0 0
(o units)
Retirement Community 0 0 0 0 0
(0 units)
Day Care 556 47 42 43 49
(7,014 s,f.)
General Office 0 0 0 0 0
(0 s.f.)
General Retail 13,606 199 127 569 616
(317,008 s.f.)
~ ~i~i~ii!i!!~ii~ ~ii~ii~!i~ ~i~!~i~ii~ii~i~i~ii!!~i ~i~i~i~i~iiii!!!!ii i :::: ::::::::::::::::::::::::::::::::: :::::::::::::::::::::::::::::::::::::::::::
ADT = average daily trips; vpd = vehicles per day; vph = vehicles per hour; in = vehicles
entering the site; out = vehicles exiting the site; and s.f. = square feet.
The trip ends in Tables 3 and 4 were distributed to and from the study site based on the site's location
with respect to area development, nearby streets and roadways, and existing traffic patterns. It
should be noted that the actual number of trips distributed was adjusted (by an average of 9.6%) to
account for two types of trips: short internal trips between residential units and retail sites that do not
reach any of the major study streets; and work related trips that include a stop at a retail site on the
way to or from work.
Page 16
PROJECTED TRAIqlqC VOLUMES
In order to conduct our analyses of the study area's traffic impact on the streets and roads serving
.the South Denton area, the Consultant developed projected traffic volumes. As previously stated,
based on assumed absorption rates the total build out of the South Denton area was calculated to
occur by the year 2016. This study addressed the ten year period of 2000 - 2010 and as such traffic
volume projections were developed for each two year period during that ten year study period.
Figures 7 through i 1 have been developed to depict the projected traffic volumes along the major
streets within the South Denton study area. Three pieces of information are provided for each street:
the projected traffic volume for that design year; the existing street cross section; and the street cross
section recommended to support the projected volume, These projected volumes consist of three
components: the 2000 traffic volume (base traffic) for that street; the through traffic volume
(background traffic) as detefJ~fined from the license plate survey; and the trip ends generated by the
South Denton area (site traffic in Tables 3 and 4) and distributed along the streets within the study
In order to account for the average annual growth in traffic due to the growth in the county's
population, the through traffic volumes were increased by an annual growth rate of 4.0%.
Page 17
HOBSON.~..
8,550
2U/2U
RYAN
13,000
20,500
4D/4D
5,150
2U/2Ui
17,500
4D/4D
14,100
4D/4D
5,350
5,250
~CREEK a~l~u/2u
10,350
2U/2U
YEAR 2002 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
1,500
4U/4U
4,850
x~/2U
ROBINSON
I
9,400
2U/4U
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
EXISTING STREET SECTION
9,250
.LU/2U
TEASLEY (FM2181)
FIGURE 7
80.55Fi96
Page 18
21,650
4D/6D
14,200
4D/4D
19,050
4D/4D
HOBSON
9,300
2U/2U
15,700
4D/4D
17,700
6,100
RYAN 2U/2u,~L
12,700
2U/4D
YEAR 2004- PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
2,500
4U/4U
1,000
-/2U
5,750
'N~/2U
J
ROBINSON
9,400
2U/4U
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
EXISTING STREET SECTION
11,500
,.Lu/4D
TEASLEY (FM2181)
FIGURE 8
8058Fig7
Page 19
20,350
4D/4D
12,850
4D/4D
15,550
4D/4D
HOBSON ~
9,900T
2U/2U
15,950
4D/4D
18,550
11,000
RYAN 2U/4Di
2,450
4U/4U
2~~ 000v
-/2U
7,150
J
ROBINSON
~CREEK
10,050
J~u/2u
14,600
2U/4D
YEAR 2006 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
9,400
2U/4U
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
EXISTING STREET SECTION
13,950
.LU/4D
TEASLEY (FM2181)
FIGURE 9
8058Fig8
Page 20
21,950
14,450
4D/4D
17,750
4D/4D
HOBSON.~..
11,o5oT
2U/4U
18,200
4D/4D
950
15,100
RYAN 2U/4D!
3,800
4U/4U
3,550
-/2u
8,700
2U/2U
J
11,950
CREEK .,
18,000
2U/4D
YEAR 2008 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
ROBINSON
9,400
2U/4U
[__
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
EXISTING STREET SECTION
16,700
2U/4D
TEASLEY (FM2181)
FIGURE 10
8058Fig9
Page 21
23,700
4D/6D
16,250
4D/4D
19,950
4D/40
HOBSON
12,300T
2U/4U
20,600
4D/4D
25,700
5,350
4U/4U
15,450
RYAN 2U/4D]L
5,250
-/2U
10,350
2U/4U
ROBINSON
14,100
,~L2u/4D
CREEK
21,800
2U/6D
YEAR 2010 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
9,400
2U/4U
19,750
k.,,,..... ,.b2U/4D
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
EXISTING STREET SECTION
TEASLEY (FM2181)
FIGURE 11
.... 8~ ~. 0
Page 22
IMPACT OF FM 2499 ON T~ TEASLEY LANE CORRIDOR
The capital improvements discussed in a previous section are needed improvements and will be
constructed at varying points in the future. However, the FM 2499 project has a significant amount
of uncertainty with regard to its construction date. In this study we have assumed that it would be
constructed in the year 2010.
Since this is a very important as well as political project, the construction date could occur well
beyond or well before the build out of the study area. As a result, we have developed Figure 12 to
illustrate the projected impact of FM 2499 on the study area streets assuming a year 2010
construction completion date for FM 2499.
We have identified three key components of the study area traffic stream that would utilize FM 2499.
The first component would be the South Denton area traffic located in the area
bounded by IH 35 on the north, State School Road on the east, Teasley Lane on the
west, and the City of Corinth on the south. This would be the most likely source to
use FM 2499. However, since the alignment of this road is on the very east edge of
the South Denton area, some of the study area traffic would still seek to utilize
Teasley Lane.
The second component would be the background traffic that passes through the South
Denton area. Our analysis assumed that approximately 50% of the possible
north/south through traffic would utilize FM 2499.
The third component would include those motorists that would seek a less congested
north/south route like FM 2499 rather than face the congested traffic operations along
Lillian Miller and Teasley Lane. As traffic volumes steadily increase and the ability
of the street system to carry and move the vehicular traffic decreases, there will be a
greater tendency for motorists to seek nearby less congested routes. This will become
very evident when capacity levels exceed the City's established acceptable level of
service '~".
Our analysis of the traffic data in Tables 3 and 4 indicated that the construction of FM 2499 would
result in a reduction of the projected traffic volumes on Lillian Miller/Teasley Lane between IH 35
and the Corinth City Limit by 15 - 20%. This reduction would result in acceptable levels of service
on the streets and roads within the study area. All service levels would be at a level of"D" or better.
Page 23
22,500
HOBSON
12,300
2U/4U
15,450
4D/4D
19,550
4D/4D
20,550
16,950
4D/4D
5,350
4U/4U
15,450
RYAN 2U/4D,~L
5,250
-/2U
10,350
2U/4U
ROBINSON
~CREEK
14,100
~L2u/4D
18,550
2U/4D
IMPACT OF FM 2499
YEAR 2010 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
17,800
9,400
2U/4U
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
--EXISTING STREET SECTION
TEASLEY (FM2181)
FIGURE 12
8C)SBF'igl 1
Page 24
ANALYSIS OF TRAFFIC STREAM COMPONENTS
For this report we have prepared Table 5 to summarize the three basic components of the traffic
volumes and projections that have been prepared for this study. The three components have been
previously identified in this report and are described as follows.
"Base" - These values represent the existing local traffic that was counted in our traffic counts
in 2000. They were derived by removing the "thru" traffic volumes (obtained in the license
plate surveys) from the 2000 counts.
'°thru' - These values are indicated in red and represent the through traffic volumes obtained
in the license plate surveys. When added to the "base" values the results equal the existing
2000 volumes.
"Dev." - These values represent the new development traffic expected to be generated by the
assumed development in the South Denton Area. When added to the "base" and "thru" traffic
values, the results equal the projected volumes.
These three values as well as their percentage of the total traffic (represented in the table by the "all"
value) have been included in Table 5.
As can be seen in the table, the "thru" traffic volumes in the exisfmg (2000) conditions represent a
significant percentage of the total traffic. As the South Denton area develops over the 10 year study
period, the percentage ofthe"thru" traffic significantly decreases in some cases while the percentage
of the "development" traffic significantly increases in all cases.
A review of the table will reveal a discontinuity in the traffic volumes beginning in the year 2006. It
was at this point that the impact of the two State School Road connector streets and the two activity
centers was introduced into the analysis. In order to simulate the resulting change in the existing
traffic patterns, we had to assume new "base", '~thm", and "dev." values - thus the discontinuity in
the traffic volume projections.
Page 25
:::::::::::::::::::::::::: ::ii::::i!::!~ oo~ ~o~ ~' ~- ~ ~o~ (q ,~ ~,~ ~o c< ~ ~ ~ ~ ~ ~ ~ ~ ~
::::::::::::::::::::::::::::::::::::
========================= ~o ~ ~ ~
~0~ oooo ooco
FINAL OBSERVATIONS
Based on the results of our analyses and the findings presented in Figures 7 - 11, we have developed
observations regarding potential intersection turn lane requirements as well as street and roadway lane
needs.
Table 6 has been developed to present the operational service level of the key streets in the study area
based on the city's capital improvement strategy. The table summarizes each street/roadway segment
with its projected cross section based on the city's current capital improvements construction
estimates for the 2000 - 2010 period.
Table 6 also includes the "level of service" associated with each street over the 10 year study period.
Levels of service begin with "A" which suggests light, flee flowing traffic with negligible interruptions
and proceed to "F" which suggests heavy, nearly stopped traffic with many interruptions. Typically
the desirable levels of service are "A" through "D" with "E" and "F" being undesirable. We have
attached a detailed description of the six possible levels of service as well as a figure that illustrates
the level of traffic congestion and vehicular density associated with each service level.
As urbanization from the Dallas metroplex area creeps northward towards Denton, citizens of this
area are going to gradually experience more and more '~oig city" type traffic congestion problems on
the City's streets. The "B" and "C" levels of service that w.e[e typically the norm in the past are going
to be replaced with "D", "E", and even "F" service levels in the future. The need to address these
future traffic congestion problems is real and should not be minimized or ignored.
It should also be noted that the levels of service presented in this report reflect the traffic operations
that are projected to occur during the peak periods of operation on each street and road. These peak
periods will typically last for one to two hours during the morning and evening commuter time
periods. The service levels during the non-peak periods are expected to occur at acceptable levels.
A review of Table 6 suggests that an aggressive approach to the funding of street improvements for
the South Denton study area may be needed. If the City of Denton continues to grow as has been
suggested in the South Denton Project report prepared by the City's Planning Department and then
expanded upon in this study, then major street widening improvements will be necessary over the next
ten years.
Also for your information we have attached a table that summarizes street capacities and their
corresponding levels of service. This was the table used to determine the service levels expressed in
this study. The values in the table were detemfined through an interpolation of values included in a
Texas Department of Transportation table that was presented to the North Central Texas Council of
Governments.
Page 29
TABLE 6
Lane Needs Based on Capital Improvement Strategy
Lillian Miller: 4D 4D 4D 4D 4D 4D
Teasley: 4D 4D 4D 4D 6D 6D
IH 35 - Londonderry "A" "D" "E" "D .... A .... A"
Teasley: 4D 4D 4D 4D 4D 4D
Londonderry - Hobson "A .... A" "A" "A" "A" "A"
Teasley: 4D 4D 4D 4D 4D 4D
Hobson - Lillian Miller "A" "A .... A" "A" "C" "D"
Teasley: 2U 2U 2U 6D 6D 6D
Lillian Miller - Robinson "F" "F" '~ .... A" "A" "A"
Teasley: 2U 2U 2U 6D 6D 6D
Robinson - Hickory Creek "B" "D/E" "F .... A" "A .... A"
Teasley: 2U 2U 2U 6D 6D 6D
Hickory Creek - City Limit "A" "C/D" "F .... A" "A .... A"
Hobson: 2U 2U 2U 2U 4U 4U
Country Club - Teasley "B .... C" '*B" "B .... A .... A"
Wind River: 4U 4U 4U 4U 4U 4U
Teasley - IH 35 "A" "A .... A" "A" "A .... A"
Ryan: 2U 2U 2U 4D 4D 4D
Country Club - Teasley "A" "A .... A" "A" 5'A .... A"
Robinson: 2U 2U 2U 2U 2U 4D
Teasley - Harvard "A" "A" "A" "A" "C .... A"
Hickory Creek: 2U 2U 4D 4D 4D 4D
City Limit - Teasley "A" "A" "A .... A .... A .... A"
FM 2499: ........ 4D
IH 35 - FM 2181 "A"
Hickory Creek: ...... 4U 4U 4U
Teasley - FM 2499 "A" "A .... A"
State School Connector: .... 2U 2U 2U 2U
Ranchman - State School "A" "A" "A" "A"
Page 30
The City should be aware that widening projects on Lillian Miller will require the attainment of
additional fight-of-way because the existing right-of-way is only 80 feet. Future sections of Lillian
Miller may require a six lane divided cross sectionl The minimum right-of-way width for such a
section is 93 feet while the desired width is 102 feet. Existing sites will lose parking and/or portions
of their side yards with significant screening walls possibly required.
However, the City has done well on several of the streets in this area and has designed and
constructed them to satisfy the anticipated growth for many years to come. These streets are listed
below.
Wind River between Lillian Miller and IH 35 will be able to adequately serve the
City's traffic demands in its present condition for the next 15 years if not indefinitely.
Teasley Lane between Londonderry and Hobson will be able to adequately serve the
City's traffic demands in its present condition for the next 12 years.
Teasley Lane between Hobson and Lillian Miller will be able to adequately serve the
City's traffic demands in its present condition for the next 10 years.
Figure 13 depicts the potential turn lane requirement needs at the key intersections within the South
Denton area. These lane needs will be highly dependent on the development of adjacent and nearby
land parcels. Because of this it is difficult to identify a forecast year by which the intersection lane
needs should be implemented.
The City should continue to review and evaluate each development site in this area for its impact on
nearby intersections. Continued developer participation should be sought in the construction of
needed intersection improvements. In this manner the ultimate intersection lane requirements will be
accomplished in a manner consistent with the traffic impact at that point in time.
Page 31
INSET "A"
_J
HOBSON
INSET "A"
SEE INSET "B"
RYAN
F-
ROBINSON
~ CREEK
POTENTIAL TURN LANE NEEDS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
L
TEASLEY
FM2181)
FIGURE 1 5
8058F igl 2
Page 32
CLOSING
C&P Engineering, Ltd. has conducted a comprehensive traffic study to assess the future infrastructure
needs with regard to the major streets and roads within the South Denton area. Based on the results
of our study Table 6 has been developed to identify the operational service levels based on the city's
current capital improvement strategy.
A review of Tables 3, 4, and 5 indicates that by the end of the 10 year study period the development
traffic will constitute the major portion of the typical traffic stream within the study area.
To address the infrastructure needs summarized in Table 6, especially on the state's facility Teasley
Lane, will require new and aggressive funding mechanisms. It is imperative that the City establish
the process to create these funding mechanisms as quickly as possible in order to implement the Table
6 lane needs in a timely manner. With the appropriate process in place the City's growth can be
maintained rather than halted or stagnated and traffic flow throughout the South Denton area can be
provided in a manner acceptable to Denton residents.
Page
LEVEL OF SERVICE
GENERAL DESCRIPTIONS
LOS
DESCRIPTION
AandB
C
D
E
F
No delays at intersections with smooth progression of traffic. Uncongested
operations; at signalized intersections all vehicles clear in a single signal cycle.
Moderate delays at intersections with satisfactory to good progression of
traffic. Light congestion; occasional back-ups on critical approaches.
40 percent probability of delays of one cycle or more at every signalized
intersection. No progression of traffic along the roadway with 90 percent
probability of being significantly stopped at every intersection experiencing
'~D" condition. Significant congestion on critical approaches, but intersection
functional. Vehicles required to wait through more than one cycle during
short peaks at signalized intersections. No long standing lines formed.
Heavy traffic flow condition. Delays of two or more cycles probable at
signalized intersections. No progression. 100 percent probability of being
significantly stopped at intersection. Limit of stable flow. Blockage of
signalized intersections may occur if traffic signal does not provide for
protected turning movements.
Unstable traffic flow. Heavy congestion. Traffic moves in forced flow
condition. Three of more cycles required to pass through signalized
intersections. Total breakdown with stop-and-go operation.
Page 34
AND BY LEVEL OF SERVICE
ROADWAY
CLASS
I
LOS A ! LOS B LOS C
I
I
LOS D
LOS E
Urban Freeways
4-lane I 44,000
6-lane 66,000
8-lane 88,000
48,400
72,600
96,800
52,800
79,200
105,600
58,600
87,900
1i7,200
64,400
96,600
128,800
LOS F
70,200
t05,300
Urban Divided Streets
4~lane 16,100 I 17,600 19,100 21,050 I 23,000 24,950
6-lane I 23,500 I 25,700 27,900 30,450 I 33,000 35,550
8-lane I 29,400 I 32,150 34,900 38,450
42,000 45,550
Urban Undivided Streets
2-lane 7,700 I 8,400 I 11,000 11,950
4-lane 12,600 I 13,750 14,900
16,450 18,000
6-lane 19.800 ! 21,650 23,500 25,900 28,300
19,550
30,700
Rural Freeways
4-lane I 20,800 I 26.200 I 31,600 I 36,800 I 42,000 47,200
6-..n~'oo ! 31,200 I 39,300 I I 47,400 55,200 ,163.000 70,800
Rural Divided Highways
6-lane i 23,400 26,600 29,800 36,600 43,400 50,200
Rural Undivided Highways
Roiling Terrain
2-lane i 2,200 i 3,000 I 3,800 I 6,900 i i0,000 i 13,100
Level Terrain
2-lane 3,20014,250 5,300 9,400113,500117,600
4-lane 9,500 11,250 13,000 15,300 17,600 19.900
6-lane
15,000 ! 17,250
19,500
23,300 !27,100 [30,900
Page 35
Exhibit #2
LEVEL OF SERVICE (LOS) EVALUATION
Congestion and the resulting delay to motorists typically occurs during the AM and PM peak travel
periods. These two periods are associated with the home-to-work and work-to-home trips and in the
City of Denton they typically occur in the rooming during the one hour period of 7 - 8 AM and in the
afternoon during the two hour period of 4:30 - 6:30 PM. The remaining 21 hours of the day are
referred to as off-peak travel periods.
During the periods of peak travel demand, motorists in metropolitan areas such as exist in the Dallas-
Fort Worth area have learned to expect congested traffic flow and delay on major roadways and
streets. During these peak periods traffic operations will typically occur at less than acceptable
service levels - LOS "E" or "F". These peak periods may function at an acceptable service level for
a portion of their time, but due to traffic volume fluctuations, a portion of the peak period may also
occur at an unacceptable level.
Conversely, during the off-peak travel periods motorists have learned to expect uneongested traffic
flow and smoother and less interrupted vehicular trips. During these off-peak periods traffic
operations will typically occur at acceptable service levels - LOS "A" through "D".
This acceptance of specific service levels associated with off-peak and peak hour travel demands has
become the norm. As a result, organizations such as TXDOT and NCTCOG develop their traffic
control and traffic management strategies and guidelines around this concept.
A key question raised was how to monitor the results of this study, that is, how do we know if traffic
growth in the study area is occurring as we have projected. If it is growing less quickly than
anticipated, the City can then choose to delay specific capital improvements or expedite development
in the area. On the other hand, if the growth is occurring more rapidly than anticipated, the City can
then choose to slow down development or expedite implementation of the appropriate capital
improvements.
We have developed a general methodology that we believe will accomplish this goal.
1. Establish six permanent count stations in the Teasley Lane study area.
Compare the count data on a monthly basis with the traffic projections developed in
this study.
Adjust the timing of the capital improvements or modify the regulatory strategy as
necessary according to the results of the comparison.
We recognize that a multitude of variables exist in attempting not only to monitor the results of this
study, but also to determine the timings, priorities, and mechanisms of the funding of related capital
improvements. As a result, it is possible and quite probable that some streets will operate at or above
acceptable service levels for extended periods of time while capital improvements arc programed and
ultimately constructed.
With this in mind we suggest that the City also monitor the length of the peak hour periods that occur
at or above a level of service "E". If traffic counts consistently indicate a period of level of service
"E" that occurs for a continuous I20 minutes or a period of level of service "F" that occurs for a
continuous 60 minutes, then special steps should be taken to ameliorate the problem. These steps
could take the form of traffic management techniques; mass transit; fast tracking of geometric
improvements; etc.
We believe that the referenced 120 and 60 minute periods are consistent with what is typically being
experienced by area motorists on major streets and highways. When vehicular delays begin to exceed
the expected norm, the dissatisfaction of motorists increases and their patience becomes even more
tested such that the safety of the driving environment is significantly threatened.
We should point out that the context within which we are describing the peak hour data, the levels
of service, and the monitoring oftbe study results is one of vehicular volumes only. The congestion,
the delays, and the dissatisfaction is predicated on a lack of capacity and not on incident situations.
In other words, we do not believe that congestion due to stalled vehicles, accidents, objects in the
roadway, or street/roadway constmction should be justification for implementing a capital
improvement project.
If congestion and delay due to incident situations is a common occurrence at a location that has
adequate capacity, then specific action should be taken to address the problem that is causing the
incident situation.
It is our belief that the ideas suggested in this document be implemented or utilized on an interim basis
until the capital improvement strategies developed as a result oftbe Teasley Lane Corridor study have
been put into place. When this occurs, motorists in the South Denton area should experience
excellent traffic operations with minimal congestion and delay.
TEASLEY LANE CORRIDOR TRAFFIC STUDY
FEBRUARY 8TM, 2000 COUNCIL WORK SESSION SUMMARY
Exhibit #3
A summary of conclusions offered during the February 8th, 2000 Council work session are listed
below, in response to the Teasley Lane Corridor Study:
Future travel demand will exceed Teasley Lane's current capacity.
At current construction rotes, Teasley Lane will experience serious safety and traffic congestion problems before
necessary roadway improvements can be programmed and constructed.
Minimum Level of Service ("LOS")
A minimum Level of Service "D" should be designated for Teasley Lane, and the rote of building permit issuance
should be regulated to match Teasley Lane's ability to accommodate increased traffic demand.
Lillian Miller Parkway improvement options are severely limited.
Lillian Miller Parkway is a four-lane divided arterial that would normally be expanded to six lanes, but because of
right-of-way cost constraints, will likely not be expanded. The Teasley Corridor improvement strategy should use
a variety of methods to reduce travel to shopping destinations and to the 1-35E connection through Lillian Miller
Parkway.
Investigate Adequate Public Facilities Requirements.
The issuance of building permits may need to be regulated using "Adequate Public Facilities" requirements. Such
an approach would create a "window" of time to allow public improvements to catch up with anticipated traffic
demand.
A Community Activity Center would divert trips from 1-35E intersections.
The designation ora "Community Activity Center" in a central location within the Teasley Study Area that
reduces shopping trips, particularly during P.M. peak hour traffic, should be considered.
Teasley Lane expansion from 2 lanes to 6 lanes should be expedited.
An aggressive capital improvements strategy should be developed to expand Teasley Lane to its ultimate design
capacity as indicated in the Roadway Component of the Denton Mobility Plan. The City of Denton ($143,000) is
prepared to participate with Denton County (143,000) and the City of Corinth ($ t 00,000) in the first stages of
project design, Environmental Assessment and Design. Expansion fi'om a two-lane rural roadway to a six-lane
divided arterial, from the Lillian Miller intersection south to the Denton / Corinth city line, should be pursued. To
expedite completion of the expansion, the City of Denton may have to consider removing F.M. 2181 (Teasley
Lane) fi'om the state highway system and assume long-term maintenance of the roadway.
The City of Corinth, Denton County, the North Central Texas Council of Govemments (NCTCOG), and the state
should be strongly encouraged to extend the six-lane improvements to the 1-35E Swisher Road exit. Denton
County and the City of Corinth intend to expand F.M. 2181 from the Swisher Road exit to Parkridge.
Teasley Lane feeder roads should also be programmed and funded for expansions.
A longer-term strategy should be developed to improve Hobson Lane, Ryan Road, Robinson Road, Nowlin Road,
and Lake Sharon Drive. Of existing feeder roads that connect to Teasley Lane, only Hickory Creek Road is
currently programmed for expansion to a four-lane collector by 200~ using Denton County CIP funding.
Construction of two new roads within the Teasley Study Area should be considered within the next ten
years.
Two new roadways should be considered during the next two CIP bond elections. The first road is F.M. 2499,
which is identified on the Denton Mobility Plan as a primary arterial intended to traverse the eastern side of the
Tcasley Study Area. Thc second road, which is not part of the Denton Mobility Plan, would connec~ the
subdivisions east of Tcasley to State School Road. These roadways need to be considered as the Study Area
approaches build-out.
Several options were discussed on February 8th, with two major options preferred by Council:
Option #1: Address Concurrency Issues
As can be noted in Table 5, many roadway segments will experience lane needs in excess of the number of lanes
currently available. When the roadway is built to ultimate design capacity, most roadway segments will operate at
acceptable Levels of Service. The challenge is to build capacity improvements (new lanes or new roads) concurrent
with the Imffic load the roadway is expected to carry. Adequate Public Facilities (APF) requirements are relatively
new, and provide an optional regulatory tool that has been used in other part of the country to address concurrency
issues. If used in the Teasley Area, APF requirements would likely slow construction activity considerably until major
capacity improvements are installed. The 1999 comprehensive plan indicates that APF requirements will be explored
by the City of Denton. An explanatory publication has been provided as Attachment 4.
The use of a moratorium is another option to consider. A moratorium would "freeze" construction activity and reduce
anticipated increases in traffic volume until necessary roadway improvements are built. The use of a long-term
moratorium could also cause negative effects such as disinvestment, stagnation of partiallY completed infrastructure
systems, or leapfrog interest in undeveloped areas outside the area subject to the moratorium.
Option #2: Increase Roadway Capacity
The City of Denton has already demonstrated a limited level of commitment to Teasley area capacity increases by
virtue of adoption of the Denton Mobility Plan in 1999 (see Attachment 3). The Plan is used to officially designate the
approximate location of new roadways and to identify existing roadways expected to be expanded (or widened).
During subdivision and plat review, right-of-way dedications are made by developers to fix the location of future
improvements, and in many instances the developer installs roadway improvements as part of a private development
project. This approach depends upon the timing of private development, and as is the case of the Teasley Lane
Corridor, home construction is anticipated to occur faster than Mobility Plan roadway improvements.
The need for capacity improvements ultimately becomes a question of funding. Several potential funding participants
include private developers, property taxpayers, sales taxpayers, city, county, state, and/or federal governments. The
funding options available will be discussed in detail when the second part of Teasley Corridor Study is prepared for
Council review on April 11a.
TEASLEY LANE CORRll)OR TRAFFIC STUDY
LAND USE DATA
Prepared for Council Discussion: ~lpril 11~, 2000
Exhibit #4
Tract Name Area in acres Number of Lots Final Platted Built
Chaucer Estates, Phase 3B 33 120 76 3
Estates of Forest Ridge, Phase 1 21 43 43 13
Hickory Creek Heights, Phase 3A 17 94 94 49
Hickory Creek Ranch, Phase 5 63 213 126 3
Oakmont II, Phase IIB 61 212 119 22
Oaks of Montecito, Phase 3B 80 232 152 35
Ridgemont, Phase I 20 74 74 34
River Oaks, Phase 5 205 677 675 105
Ryan Ranch, Phase 3B 115 275 77 0
Summit Oaks, Phase 2A 78 332 160 32
Sundown Ranch, Phase 2A 173 433 287 61
Thistle Hill, Phase 3A 53 129 36 0
Wind River Estates, Phase 2A 136 434 316 158
Wynstone at Oakmont, Phase 4B 99 556 252 2
tOTAL 1154 3824 2487 517
Average Density 3.3
(New means approved since 1/1/97)
(Phase listed is most current phase)
Tract Name Area in acres Number of Lots Final Platted Built
Bent Oaks, Phase 1 16 41 41 25
Denton West MHP, Phase 1 56 307 307 249
Forest Ridge, Phase 1 162 317 317 224
Lakewood MI-IP, Phase 2B 80 410 410 238
Montecito del Sur 93 116 116 70
Montecito, Phase 1 146 90 90 88
Southmont, Phase 1 9 31 31 26
Total 562 1312 1312 920
Average Density 2.3
(Old means approved prior to 1/1/97)
Tract Name Area in Acres Max. Number of Lots Final Platted Built Zoning
Briscoe- Clark 23 74 0 0 SF-7
Kirby Tract 39 143 0 0 !PD
Lexington Park (Freeman) 58 254 0 0 SF-10
Shadow Brook 34 92 0 0 SF-16
Teasley Harbor 35 133 0 0 SF-7
Top of the Hill 65 243 0 0 PD
Unicom Lake 22 127 0 0 PD-20 for SF-10
Wheeler Ridge 152 628 0 0 PD
TOTAL 428 1694 0 0
Average Density 4.0
Tract Name Area in Acres Max. Number of Lots Final Platted Built
Acme Brick 83 291 0 0
Forester Tract 37 130 0 0
Helm Drive Tract 181 529 0 0
Kirby Tract 6 21 0 0
Nowlin Road Tract 9 39 0 0
NW Hickory Creek, Teasley 77 270 0 0
Oakmont Area 24 84 0 0
Ryan Tract 80 280 0 0
South of Bent Oaks 30 t30 0 0
South Shadow Brook 30 11 11 8
Stewart Tract 56 196 0 0
SW Hickory Creek, Teasley 51 179 0 0
TOTAL 664 2160 11 8
(3.5 units per acre multiplier used)
l//lllll
Density
Tract Name Area in Acres Max. Number of Units Final Platted Built Zoning (dua)
Archer Tract 10 170 0 0 PD 17
Good Samaritan - Retirement 157 1170 0 0 PD 7.5
PD-100 29 254 0 0 PD varies
Unicom Lake 30 660 0 0 PD 21
TOTAL 226 2254 0 0
Average Density 10.0
Name Area in Acres
Unicom Lake 33
St. Marks Church 13
Southmont Church 8
Library/Fire Station 3
Sam Houston Elementary 15
McNair Elementary 13
TOTAL 85
Name Area in Acres Zoning Final Hatted Built
Unicom Lake 55 PD-20 0 0
Archer Tract 4 GR 0 0
KDNT 20 A 20ac. 20ac.
PD- 100 2 PD for GR 0 0
PD- 16 9 PD for GR 0 0
Robinson/Teasley 3 GR 3ac. 3ac.
Ryan/Teasley 1 GR 1 ac. 1 ac.
Teasley Harbor 2 NS 0 0
Teasley Office District 17 O 17ac. 0
Wheeler Ridge 15 PD for GR 0 0
TOTAL 128 41ac. 24ac.
South Denton and Teasley Lane Corridor Study GIS Map located in Exhibit
File
AGENDA INFORMATION SHEET
AGENDA DATE: April 11, 2000
DEPARTMENT:
ACM:
Utility Administration
Howard Martin, 349-8232
SUBJECT:
Consider approval of the Preliminary Design Report by Freese & Nichols for the Modifications
to Lake Ray Roberts Surface Water Treatment Plant.
BACKGROUND:
On August 23, 1999, staff held a discussion with the PUB regarding the advantages and
disadvantages of building a 10-mgd vs. 20-mgd treatment capacity at the proposed Lake Ray
Roberts Water Treatment Plant (LRRWTP). Based on this discussion, the PUB recommended
moving forward with the design of a plant with a 20-mgd capacity. Staff presented the PUB
recommendation to the City Council in the workshop session on August 24, 1999. The City
Council also endorsed the PUB recommendation to move forward with the 20-mgd design.
Staff has worked with the consulting firm of Freese and Nichols, Inc. who were the original
designers of the 10-mgd plant in 1990, to develop the scope of work and cost proposal for the
preliminary design of the 20-mgd LRRWTP. The decision to undertake the preliminary design
was made as several process units have to be modified to meet the current regulations; and
instrumentation and Supervisory Control And Data Acquisition (SCADA) system technology has
changed drastically since 1992. The preliminary design will help identify the design changes
that need to be made and the feasibility of the alternative designs and costs for each alternate.
The preliminary design effort then will help to develop the scope and costs associated with
developing plans and specifications for the final design of the LRRWTP. The contract for the
preliminary design effort and final report was approved by the PUB on October 4, 1999 and by
the City Council on November 2, 1999. The consultants scope of services and the cost proposal
are attached as Exhibit II.
During the preliminary design process, the Water Utilities Department formed a review team
comprised of staff members from the administration, engineering and water production divisions.
This review team met with the consultant in a series of two and three day workshops to review
the consultant's progress, facilitate guidance and direction on preliminary design decisions, and
to provide staff with a more detailed understanding of the project leading into the design phase.
Two significant recommendations that resulted from these workshops included the addition of
ozonation facilities with the initial plant construction and the relocation of the ground storage
and high service pump station facilities from the Hartlee Field Road site to the LRRWTP site.
Staff provided an update on the economic and regulatory justification of these two
recommendations to the PUB on January 24, 2000 and to the City Council on February 8, 2000.
The preliminary design effort has identified the desired design modifications for the LRRWTP
facilities. It also determined the estimated construction costs for these facilities to be
incorporated into the FY 2001 - 2005 Water Utilities Capital Improvements Plan. The report
also provides the basis for staff to identifying the scope of services and negotiate a professional
services agreement with Freese & Nichols, Inc. for completing the final design of the facilities.
OPTIONS:
Approve the preliminary design report as submitted.
Recommend desired changes to the preliminary design report.
RECOMMENDATIONS:
Staff recommends approval of the preliminary design report as submitted by Freese and Nichols,
Inc.
PRIOR ACTION REVIEW (COUNIL, BOARDS, COMMISSION)
August 23, 1999 - Discussion on the LRRWTP cost update and 10-mgd vs 20-mgd plant
construction.
October 4, 1999 - Approval of the preliminary design contract with Freese & Nichols,
Inc.
January 24, 2000 - Receive an update from staffon the major decisions and
recommendations from the preliminary design report workshops.
City Council:
August 24, 1999 -Discussion on the LRRWTP cost update and 10-mgd vs 20-mgd plant
construction.
November 2, 1999 - Approval of the preliminary design report contract with Freese &
Nichols, Inc.
February 8, 2000 - Receive an update from staff on the major decisions and
recommendations from the preliminary design report workshops.
ESTIMATED SCHEDULE OF PROJECT:
The plant should be operational by the late summer of 2002. The current schedule for the project
is detailed in Exhibit IV.
FISCAL INFORMATION:
The professional services agreement with Freese & Nichols, Inc., for the preliminary design
report was based upon a lump sum amount of $142,700. The estimated construction cost of the
20-mgd plant facilities including the raw water pumping station, ozonation facilities, ground
storage and high service pumping station facilities is approximately 35 million dollars.
A detailed breakdown of these costs is included in the preliminary design report (Exhibit III). A
summary comparison of the costs for these facilities from the FY 2000-2004 Water Utility
Capital Improvements Plan and the 1998 Capital Improvements Plan for Water and Wastewater
Impact Fees (Duncan Associates) is shown in Exhibit V.
Based upon the estimated construction costs identified for this project in the preliminary design
report, this project can be funded without an anticipated rate increase provided impact fee
revenues match current projections.
See Exhibit I
Respectfully submitted:
Assistant Director of Water Utilities
Exhibit I
Exhibit II
Exhibit III
Exhibit IV
Exhibit V
- Location Map
- Freese and Nichols Scope of Work and Cost Proposal
- Preliminary Design Report for the Modifications to Lake Ray Roberts WTP.
- Project Schedule
- Cost comparison summary
$
~4
~ fie, id Road
Pump
D4ENTON
EXHIBIT 1
J.'..A,-cviev~h'o~ectsWay Robert~ W'i'P.
September 28, 1999
FREESEoNICHOL$
Mr. P.S. Arora, P.E.
City of Denton Water Utilities
215 E. McKinney
Denton, TX 76201
Proposal for Preliminary Design Phase
Lake Ray Roberts Water Treatment Plant
City of Denton
Off99050/DT63/1160
Dear Mr. Arora:
The attached spreadsheet is the basis for our estimate of hours and costs to prepare a revised
Preliminary Design Report for the Lake Ray Roberts Surface Water Treatment Plant. The
design team for the preliminary phase includes Freese and Nichols, Montgomery Watson,
and Gary Juren Architects. Montgomery Watson will prepare the elements of the PDR
related to the electrical and instrumentation design. Gary Juren, the original architect will
be involved in an advisory role on the revisions to the Administration Building. Freese and
Nichols will complete all of the other tasks, inclusive of overall project administration. Our
previously submitted scope and the attached fee are based on the following:
Reliance on previous design and analysis, to the extent possible.
Increase of the plant design flow from 10 MGD to 20 MGD.
Process and design changes will be evaluated and determined in a workshop
setting with the D~3,~' staff in FNI's Ft. Worth office, per our letter dated
August 27, 1999.
Additional su~'ey and geotechnical work will be contracted directly by the
City. It is currently anticipated that the existing info~ixxation will be adequate
for the revision to the PDR.
City of Denton Professional Services Agreement is to be used.
The estimated fee is $142,700. This is approximately one-fourth of the original preliminary
design phase fee, when the two are compared on a common year basis. This represents a
salvage value of our original work of about 75%. For the preliminary design phase we
request the compensation basis be lump sum, since the scope is clear and it will facilitate
project administration.
Freese and N~chols. Inc Engineers Enwronmen[al Sc~er~t~sts Architects
4055 Internat~ona~ Plaza Suite 200 Fort Worth, Texas 76109-4895
817-735-7300 Fax 817-735-7491
EXHIBIT II
Mr. P.S. Arora, P.E.
August 6, 1999
Page 2 of 2
In that there have been several modifications in the ~'ederal regulations pertaining to water
quality and site accessibility and safety, and there have been significant advances in the water
treatment industry in the past 10 years, it is expected that substantial modifications may be
required to the final design elements. These will be presented, evaluated and decided upon
by the City during the planned workshops. Upon completion of the PDR, an estimate of
hours and cost for the final design and construction phase will be prepared based on the
elements modified or supplemented.
We hope that this information assists you in your decision process and, if you need further
information, please contact us.
Very truly yours,
Freese & Nichols, Inc.
R/x~ond R. Longoria
Principal
[of'tggO50Jtl,T: LETPDR COST PROPOSAL REV 0l WPD
'.r
X
Ltl
CITY OF DENTON
REPORT ON LAKE
RAY ROBERTS
SURFACE WATER
TREATMENT
PLANT
PRELIMINARY
DESIGN
CITY OF DENTON
MODIFICATIONS TO
LAKE RAY ROBERTS
SURFACE WATER TREATMENT PLANT
PRELIMINARY DESIGN
PROJECT DTN99479
MARCH 2000
Prepared for
FREESE ° NICHOLS
Freese and Nichols, Inc.
4055 International Plaza
Suite 200
Fort Worth, TX 76109
$17/735-7300
03-24-00 FINAL - MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Executive Summary
EXECUTIVE SUMMARY
ES.1 PROJECT BACKGROUND
The 10~mgd Lake Ray Roberts Water Treatment Plant (LRRWTP) for the City of Denton
Water Utilities (DWU) was originally designed by Freese & Nichols, Inc. (FNI) in 1990/91, but
was not constructed due to the City's re-evaluation of water demand projections. The original
design included the 10-mgd Raw Water Pump Station and Pipeline from Lake Ray Roberts and
the 10-mgd Conventional Water Treatment Plant. A separate but related project was the 35-mgd
Hartlee Field Road Storage and High Service Pump Station project. The combined cost for those
two projects, if built now, would be $27 million (estimated Year 2001 construction costs).
Growth in Denton and Denton County in the last half of the decade and the associated
increase in water usage/demand prompted the City to reinitiate the treatment plant construction
project. A primary goal was to utilize as much of the previous design as practical to shorten the
project implementation time and reduce costs. The DWU staff took a three-step approach to
detemdning the best course of action. The first step updated the projection of water needs for the
City of Denton and its customers. The second looked at the continued suitability of a plant at the
existing site. The third identified the required and the recommended modifications to the
original WTP to account for the regulatory, site condition, and technology and operational
strategy changes in the water industry since 1991.
The "Long-Range Projections of Population and Water Requirements"(Apdl, 1999)
updated the demand projections and suggested that a total of 20-mgd of treatment plant capacity
should be added by the year 2002. The "Letter Report on Site Suitability" (January 1999),
determined the existing site was still the preferred site.
The third step, the required and recommended modifications to the plant design, is
covered in this report.
ES.2 REQUIRED AND RECOMMENDED CHANGES
The 1991 plant design was evaluated with respect to changes in:
1. US Environmental Protection Agency (USEPA) and Texas Natural Resource
Conservation Commission (TNRCC) regulations
2. Site conditions
3. Treatment technology and' equipment
4. DWU WTP operational and staffing strategies
5. DWU treated water distribution strategies
ES- 1
03-24-00 FINAL- MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Executive Summary
There are specific changes that were made in direct response to regulations that have
been enacted since 1991. There were other changes that were regulation driven but allowed for
alternative approaches for compliance. In those cases, technical and economic alternative
evaluations were prepared and recommendations made.
The three major changes in the plant design are 1) Increase in plant capacity from 10 to
20 mgd, 2) Change from Conventional Coagulation treatment and Chlorine Disinfection to
Pre. Ozonation with Conventional Coagulation and Ozone Disinfection, and 3) Relocation of
Treated Water Storage and High Service Pumping from the Hartlee Field Road site to the
LRRWTP site. The first change resulted from the updated water demand projection work. The
second was the result of a technical and economic evaluation prompted by proposed
USEPAfrNRCC regulations. The third was the result of a technical and economic evaluation
prompted by the change from the LRRWTP being a regional treated water provider to being
principally a treated water provider for the City of Denton. In all three cases, the recommended
alternative was the lowest cost option using a standard 20 year life-cycle cost basis.
Other significant modifications include:
1. Addition of Raw Water Splitter Box. Increase of plant size from 10 to 20 mgd
requires that an additional treatment train be added. Of the alternatives evaluated,
the hydraulic splitter box was recommended due to ease of maintenance, accuracy
and cost.
2. Filter Modifications. The concept and overall configuration of the filters
remains unchanged. However, process enhancements were recommended to
improve the filtered water quality. The modifications include a) change from
surface wash to air scour during backwash; b) addition of filter-to-waste
capability; and c) change from conventional dual media filters to deep bed GAC
filters.
3. Chlorine and Ammonia Storage and Feed. Current regulations and overall site
safety issues are the basis for changing the approach on chlorine and ammonia
chemical storage on site. These chemicals will be stored in fewer but larger bulk
containers and will be enclosed in areas with air scrubbing systems to handle and
treat any accidental releases. A preliminary equipment arrangement and layout is
presented in this report. The ultimate sizing and configuration of the bulk storage
and chemical feed equipment and scrubbers will be finalized in a design
workshop.
4. Slurry Trench Wall for Containment of Groundwater. Freese and Nichols
determined that the elevated groundwater level at the site would adversely impact
the filters, washwater reclamation basin, and the interim filtered water pump
station. The area for these facilities (current and future) is to be isolated from the
ES - 2
03-24-00 FINAL - MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Executive Summary
groundwater using a bentonite clay slurry trench wall. Permanent pumping
facilities and monitoring wells are included.
5. Back Up Power System. The relocation of the HSPS from the Hartlee Field
Road site to the LRRWTP site requires a high level of reliability of power supply
to the site. The distance from the nearest independent electric power substation
(City of Denton, or other electric power supplier) to the site makes back-up power
via dual feed economically unattractive. Additionally, the control of reliability of
electric power to the site would diminish if the City of Denton Electric Utility
were to be sold as a result of the imminent electric power industry deregulation.
Accordingly, back up power in the form of diesel powered generators has been
added to the LRRWTP.
6. Administration/Operations Building. The basic overall dimensions and
exterior appearance remain unchanged. One comer of the building that originally
was covered but not enclosed has been enclosed. The interior of the building was
modified extensively to comply with the current requirements of the Americans
with Disabilities Act (ADA) and the Uniform Building Code (UBC) and to make
the interior space more functional.
An overview of the current plant site and plant hydraulics is given in Figures ES-1 and
ES-2, respectively. The site layout drawing illustrates the original facilities, the modified
facilities, and the new facilities. The current design includes a 20-mgd Raw Water Pump Station
and Pipeline from Lake Ray Roberts, the 20-mgd Ozone Water Treatment Plant, a 6 MG Storage
Tank and the High Service Pump Station facilities.
The estimated opinion of probable construction cost for the current 20-mgd raw water
conveyance, LRRWTP with ozone treatment/disinfection and the relocated Hartlee Field Road
storage tank and High Service Pump Station is approximately $35 million dollars. A breakdown
of the major construction components is given in Table ES-1.
The current Implementation Schedule is given in Figure ES.3. The current schedule
estimates substantial completion at 18 months, with final completion requiring and additional 2
to 4 months. Substantial completion for the LRRWTP is defined as all units being in operation,
with the exception of the ozone facilities, the back-up power facilities, and the SCADA Control
System. The plant will rely on chlorination/chloramination disinfection for start-up, single
source power supply and manual control.
ES.3 PRELIMINARY DESIGN REPORT FORMAT
This report serves as an addendum to the original report "Lake Ray Roberts Water
Treatment Plant - Final Preliminary Design Report, April 1990". The information or
ES - 3
03-24-00 FINAL - MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Executive Summary
TABLE ES-1
Opinion of Probable Construction Cost Summary
Lake Ray Roberts Water Treatment Plant
City of Denton
Facility
Raw Water Pump Station and
20 MGD Ozone WTP
High Service Pump Station and
Total:
Estimated
recommended facilities from the original report remains valid unless modified in the current
Preliminary Design Report. In the current report, Section I- Introduction gives the project
background and scope of the work. The information in Sections 2 - 12 present the information
on the areas of the plant that is to be modified. Section 13-Recommended Facilities gives a
summary description of the current design. Section 14 - Opinion of Probable Construction
Costs presents the estimated project costs.
ES - 4
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Table of Contents
TABLE OF CONTENTS
CHAPTER ............................................................................................................................ PAGE
CHAPTER 1.0 INTRODUCTION ........................................................................................... 1-1
1.1 PROJECT AND REVIEW BACKGROUND .................................................~ ......... 1-1
1.2 REGULATORY REVIEW ........................................................................................ 1-2
1.3 ALTERNATIVE CHEMICAL TREATMENT EVALUATION .............................. 1-2
1.4 RAW WATER SPLITTING AND CHEMICAL MIXING ...................................... 1-3
1.5 GROUND WATER CONTROL ............................................................................... 1-3
116 FILTER DESIGN ...................................................................................................... 1-3
1.7 HIGH SERVICE PUMP STATION AND STORAGE ............................................. 1-3
1.8 SLUDGE MANAGEMENT ...................................................................................... 1-4
1.9 ADMINISTRATION BUILDING ............ i ................................................................ 1-4
1.10 HYDRAULIC ANALYSIS ....................................................................................... 1-5
1.11 BACKUP POWER SUPPLY .................................................................................... 1-5
1.12 INSTRUMENTATION AND CONTROL ................................................................ 1-5
CHAPTER 2.0 REGULATORY REVIEW ............................................................................. 2-1
2.1 PURPOSE .................................................................................................................. 2-1
2.2 EXISTING AND PROPOSED DRINKING WATER REGULATIONS ................. 2-1
Disinfectants and Disinfection By-Products Rule (D/DBP) Stage 1 ................... 2-1
Requirements ..................................................................................................... 2-2
Compliance ........................................................................................................ 2-3
Interim Enhanced Surface Water Treatment Rule (IESWTR) ............................ 2-6
Requirements ............................................................................... 2-6
Compliance ..................................................................................................... 2-7
2.3 ANTICIPATED FUTURE DRINKING WATER REGULATIONS ........................ 2-7
Long-term (Stage 2) D/DBP Rule ........................................................................ 2-7
Requirements ....................................................................................................... 2-8
Compliance ........................................................................................................ 2-8
Compliance Schedule ........................................................................................... 2-8
Long-term Enhanced Surface Water Treatment Rule (LTESWTR) .................... 2-8
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Table of Contents
Requirements ........................................................................................................................ 2-8
Compliance .............................................................................................................................. 2-8
Compliance Schedule ................................................................................................................. 2-9
2.4 RISK MANAGEMENT PROGRAM (RMP) ..........................................................2-11
2.5 SEPTIC SYSTEM DESIGN CRITERIA REVISION ............................................. 2-13
CHAPTER 3.0 ALTERNATIVE CHEMICAL TREATMENT
EVALUATION (OZONE) ......................................................... 3-1
3.1 PURPOSE .................................................................................................................. 3-1
3.2 REGULATORY REQUIREMENTS AND ALTERNATIVE EVALUATIONS ..... 3-1
Stage 1 D/DBP Compliance .............................................................3-2
Stage 2 D/DBP Compliance .............................................................3-3
Ozone Treatment Process ..............................................................3-3
3.3 ECONOMIC ANALYSIS BETWEEN ENHANCED COAGULATION AND
OZONE ALTERNATIVES ....................................................................................... 3-4
3.4 RECOMMENDATION ............................................................................................. 3-6
CHAPTER 4.0 RAW WATER SPLITTING AND CHEMICAL MIXING ...................... 4-1
4.1 PURPOSE .................................................................................................................. 4-1
4.2 RAPID MIX SYSTEM/CHEMICAL ADDITION OPTIONS ................................. 4-1
4.3 RECOMMENDATION ............................................................................................. 4-2
CHAPTER 5.0 GROUND WATER CONTROL .................................................................. 5-1
5.1 PURPOSE .................................................................................................................. 5-1
5.2 GROUNDWATER MITIGATION ALTERNATIVES ................................. 5-1
5.3 RECOMMENDATION ............................................................................................. 5-2
CHAPTER 6.0 FILTER DESIGN .......................................................................................... 6-1
6.1 PURPOSE .................................................................................................................. 6-1
6.2 ALTERNATIVE CONFIGURATION ...................................................... 6-1
6.3 RECOMMENDATION ............................................................................................. 6-1
CHAPTER 7.0 HIGH SERVER PUMP STATION AND STORAGE ................................ ?-1
7.1 BACKGROUND ....................................................................................................... 7-1
7.2 STORAGE TANKS ................................................................................................... 7-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Table of Contents
7.3 PUMP STATION LAYOUT ..................................................................................... 7-2
7.4 ELECTRICAL AND INSTRUMENTATION .......................................................... 7-3
7.5 DISCHARGE PIPELINE ........................................................................... ~ .............. 7-3
CHAPTER 8.0 SLUDGE MANAGEMENT ......................................................................... 8-1
8.1 PURPOSE .................................................................................................................. 8-1
8.2 ALTERNATIVE EVALUATION ............................................................................. 8-1
8.3 RECOMMENDATION ......... i ................................................................................... 8-2
CHAPTER 9.0 ADMINISTRATION BUILDING ............................................................... 9-1
9.1 PURPOSE .................................................................................................................. 9-1
Project Background .............................................................................................. 9-1
Original Building Description .............................................................................. 9-1
9.2 BUILDING REVISIONS .......................................................................................... 9-2
Revised Design Criteria ....................................................................................... 9-2
Design Concepts .................................................................................................. 9-2
Planning Procedures ............................................................................................. 9-3
Cost Differences ................................................................................................... 9-3
9.3 RECOMMENDATION ............................................................................................ 9-4
CHAPTER 10.0 HYDRAULIC ANALYSIS ....................................................................... 10-1
10.1 PURPOSE ................................................................................................................ 10-1
10.2 HYDRAULIC PROFILE ......................................................................................... 10-1
CHAPTER 11.0 BACKUP POWER SUPPLY EVALUATION ........................... ~ ........... 11-1
11.1 PURPOSE ................................................................................................................ 11-1
11.2 EVALUATION ANALYSIS ................................................................................... 11-1
Load Evaluation ................................................................................................. 11-1
Cost Comparisons .............................................................................................. 11-1
11.3 RECOMMENDATION ........................................................................................... 11-2
CHAPTER 12.0 ELECTRICAL/INSTRUMENTATION AND CONTROL .................. 12-1
12.1 PURPOSE ............................................................................. ~ .................................. 12-1
12.2 ALTERNATIVE EVALUATION ........................................................................... 12-1
12.3 RECOMMENDATION ........................................................................................... 12-3
iii
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Table of Contents
Description of Recommended Control System .................................................. 12-3
CHAPTER 13.0 RECOMMENDATIONS .......................................................................... 13-1
13.1 RECOMMENDATIONS ......................................................................................... 13-1
13.2 BULK CHLORINE/AMMONIA STORAGE AND FEED ............................ 13-2
CHAPTER 14.0 PROBABLE CONSTRUCTION COSTS ............................................... 14-1
iv
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Table of Contents
List of Figures
Figure ...................................................................................................... Page
ES-1 Modified Site Layout .................................................................................. After Page ES-3
ES-2 Modified Hydraulic Profile ......................................................................... After Page ES-3
ES-3 Construction Schedule ................................................................................ After Page ES-3
3.1 Preozone Contactor Plan and Section ............................................................ After Page 3-6
3.2 Intermediate Ozone Contactor Plan and Section ........................................... After Page 3-6
3.3 Ozone Building Layout .................................................................................. After Page 3-6
4.1 Splitter Box Plan and Section ........................................................................ After Page 4-2
5.1 Slurry Trench Wall Layout ............................................................................ After Page 5-2
6.1 Filter Site Plan .................................................................. i ............................. After Page 6-2
6.2 Filter Sectional Plan ....................................................................................... After Page 6-2
6.3 Filter Sections ................................................................................................ After Page 6-2
7.1 High Service Pump Station Floor Plan .......................................................... After Page 7-2
7.2 High Service Pump Station Typical Section .................................................. After Page 7-2
7.3 High Service Pump Station Layout ................................................................ After Page 7-4
9.1 Operations Building First and Second Floor Plan ......................................... After Page 9-4
10.1 Modified Hydraulic Profile .......................................................................... After Page 10-1
I 1.1 Backup Power Generator Layout ................................................................. After Page 11-3
13.1 Modified Site Layout ................................................................................... After Page 13-1
13.2 Ammonia and Chlorine Feeding System Plan View ........................... After Page 13-3
MODIFICATIONS TO LRR WTP PRELIMINARY DESIGN
Table of Contents
List of Tables
Table
ES-1
2-1
2-2
.................................................................................................................................... Page
Opinion of Probable Construction Cost Summary ..........................................ES-4
New Drinking Water Goals and Standards of the D/DPP Rule ............................ 2-5
Required Percent Removal of TOC Required by
Enhanced Coagulation/Softening ............................................................... 2-5
2-3 Existing and Proposed Regulatory Requirements Summary ................................ 2-10
2-4 Additional DCHD Septic Tank Design Criteria .............................................. 2-13
3-1 Estimate of Chemical Cost Savings with Pre-Ozonation ..................................... 3-7
6-1 Filter Design Parameters .......................................................................... 6-3
13-1 Preliminary Design Criteria ..................................................................... 13-4
14-1 Opinion of Probable Construction Cost ....................................................... 14-2
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03/24/00 FINAL - MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Introduction
CHAPTER 1.0 INTRODUCTION
1.1 PROJECT AND REVIEW BACKGROUND
The 10 MGD LRRWTP for the City of Denton was originally designed by FNI in 1991,
but it was not constructed due to the City's re-evaluation of water demand projections. The water
demand projections suggested that the City could supply adequate water on an interim basis from
the existing Lake Lewisville WTP. The growth in Denton and Denton County in the last ten
years and the associated increase in water usage has prompted the City to move ahead at this
time with the construction of the LRRWTP project. Current water demands suggest that a new
plant with a 20 mgd capacity needs to be operational by year 2002.
Since 1991, there have been significant changes in the design and operation of water
treatment plants in the United States. These changes were driven by both new drinking water
regulations and technological changes. For example, chlorination was considered a standard
disinfection strategy in the early 90s; but its usage is being discouraged currently due to stricter
chlorination byproduct limits set by the EPA. The major technical changes include changes in
chemical mixing equipment, filter design and control, sludge dewatering processes and
instrumentation and control equipment.
Another design element in the LRRWTP that has changed significantly over the years is
the Administration building design. Since 1991, several editions of the Uniform Building Code
(UBC) have been issued, some of which have changed life safety issues in the design of this
building. There have also been major changes in handicapped requirements (Americans with
Disabilities Act) over that same period. In addition, there are areas where the City's criteria used
to plan the buildings have changed.
There also have been permanent changes in the groundwater conditions at the proposed
LRRWTP site. These changes in the groundwater conditions were first observed during the
original design period, (1990/91). The initial, rapid filling of Lake Ray Roberts appeared to
impact the groundwater levels surrounding the lake, including the groundwater at the proposed
LRRWTP site. Observations of the groundwater levels during 1998 and 1999 suggested that the
impact wa~ permanent. Thc observed groundwater level warranted an evaluation of groundwater
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03/24/00 FINAL - MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Introduction
control strategies at the LRRWTP to insure the structures could be safely maintained over a long
term period using the original design.
The original concept for the LRRWTP design was to have most of the water storage at
the Hartlee Field Road Pump Station (HFRPS). The major reason for this concept in 1991 was
that the LRRWTP was intended to serve as a regional plant, and the wholesale customers would
provide their own storage. Now, the LRRWTP is intended to serve mostly the City of Denton.
Therefore, a comparative study was needed to determine any cost savings in locating the HFRPS
at the LRRWTP site.
This revised preliminary design report presents the changes to be included in the original
design to comply with the new regulations, water demands, and additional issues such as changes
in groundwater level and technologies.
1.2 REGULATORY REVIEW
Since the completion of the original LRRWTP design in 1991, there have been
significant regulatory changes in the design and operation of water treatment facilities. The City
requested that FNI review the existing and proposed drinking water regulations, risk
management program (RMP) requirements, Americans with Disabilities Act (ADA), and
Uniform Building Code (UBC) requirements applicable to the LRRWTP and recommend design
modifications in meeting those regulations and the projected water demands. Chapter 2 -
Regulatory Review identifies .the requirements of the existing and proposed drinking water rules,
RMP and septic tank design. Compliance strategies of these regulations were also developed in
this chapter.
1.3 ALTERNATIVE CHEMICAL TREATMENT EVALUATION
Since 1991, there also have been significant drinking water regulatory changes. Recently
promulgated regulations would require the plant to operate in enhanced coagulation mode,
increasing the cost of operation and possibly making turbidity removal more difficult. Chapter 3-
Alternative Chemical Treatment Evaluation (Ozone), presents the results of the enhanced
coagulation study and an economic comparison between enhanced coagulation and ozonation
procc~e~. Ozonation for conditionin~ of water and disinfection was recommended to comply
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03/24/00 FINAL - MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Introduction
with the new regulations. Ozonation involves a high capital cost but can offer reduction in
operating costs and would produce a higher quality finished water.
1.4 RAW WATER SPLITTING AND CHEMICAL MIXING
Flow splitting had not been designed in the initial design since there was only one 10
MGD train to be constructed. Since the modified plant's rated capacity will be 20 MGD with two
I0 MGD trains, a means of splitting flow to each treatment train will need to be constructed.
The rapid mix/chemical addition system design was also reviewed with respect to being
constructed jointly with the recommended flow splitting structure. Three rapid mix/fiow
splitting system alternatives were selected for evaluation and are described in Chapter 4-Raw
Water Splitting and Chemical Mixing. Maintaining the pump diffusion system for chemical
mixing, and adding a hydraulic flow splitter box are recommended.
1.5 GROUND WATER CONTROL
At the time of initial design, Lake Ray Roberts was being filled and the groundwater
levels surrounding the lake, including the proposed plant site, were impacted. Piezometers were
installed at the plant site and have been monitored periodically since that time. Observations
made in 1998 and 1999 suggest that the change to the groundwater level is permanent. Under
the original plant hydraulic design the filters, clearwell, washwater reclamation basin and main
drain pump station foundations would be below the observed groundwater level (by
approximately five to twenty five feet). This condition presented a threat to the treated water
quality inside basins and to the structures themselves. Chapter 5-Groundwater Control presents
different alternatives to keep the treatment units protected from. Construction of a slurry trench
wall and dewatering pumps is recommended.
1.6 FILTER DESIGN
Chapter 6-Filter Design identifies the filter design changes to be made to comply with the
new regulatory requirements and provide filter technologies that are compatible with the
ozonation process. Three different layouts of filters were evaluated. A layout similar to the
original design is recommended, with the addition of air scour for backwashing, deep bed GAC
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Introduction
with a sand cushion in lieu of the dual media as the recommended filter media and filter to waste
capabilities to minimize turbidity spikes.
1.7 HIGH SERVICE PUMP STATION AND STORAGE
The original concept for the development of the LRRWTP was to have most of the water
storage at the HFRPS. The major reason for developing this concept in 1991 was that the
LRRWTP was intended as a regional water plant, and the customers would provide their own
storage to meet peak demands. Now, the LRRWTP is intended to serve only the City of Denton.
A study was performed by FNI comparing the costs of locating the high service pump station and
storage tanks at either HFRPS or LRRWTP sites. The results of this study are included in a
memo dated January 8, 2000. In this study, FNI recommended eliminating the HFRPS and
locating the 60 MGD (ultimate) high service pump station at the LRRWTP site. Chapter 7-High
Service Pump Station and Storage provides the preliminary design of a 60 MGD (ultimate) high
service pump station with a 6.0 MG ground storage tank at the LRRWTP site.
1.8 SLUDGE MANAGEMENT
Chapter 8-Sludge Management presents an evaluation of different sludge dewatering
options. Among the four alternatives considered, the sludge dewatering by a centrifuge was the
least expensive initial cost option. However, there is little operational experience using
cen.trifuges for dewatering ferric hydroxide sludge. Therefore, we recommend that the sludge
lagoons be constructed as originally designed due to the proven operational performance and the
reduced operating and maintenance requirements.
1.9 ADMINISTRATION BUILDING
Since 1991, when the initial administration building was designed by Gary Juren, Inc.,
several editions of the Uniform Building Code (UBC) have been issued, some of which have
changed life safety issues used in the design of this building. There have also been significant
changes in handicapped requirements (Americans with Disabilities Act) over that same period.
In addition, there are areas where the Owner's criteria used to plan the buildings has changed.
The existing drawings were evaluated in regard to these changed conditions and the original
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03/24/00 FINAL - MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Introduction
design modified to reflect the revisions necessary to comply with the latest regulatory
requirements.
1.10 HYDRAULIC ANALYSIS
Due to the addition of several new treatment units the plant hydraulics were recalculated.
Chapter 10-Hydraulic Analysis presents an evaluation of the gradeline through the plant, and the
revised hydraulic profile.
1.11 BACKUP POWER SUPPLY
When constructed, the LRRWTP and HSPS will become a significant source of treated
water for the Denton water supply system. Backup power will be required to meet the TNRCC
delivery requirements. The reliability of service from the Denton Electric Utility may diminish if
the system is owned, or controlled and operated by others. Alternatives for a secure power
source were examined to maintain reliability of production. Chapter 11-Backup Power Supply
covers the backup power supply alternatives considered and recommends the addition of diesel
generators for backup power.
1.12 INSTRUMENTATION AND CONTROL
The original design utilized a Distributed Control System (DCS) for plant automatic
control and monitoring. Since that time, there have been significant changes in control system
technology and instrumentation systems that can be applied to the control and monitoring of the
plant. Two alternatives were evaluated and direct communication link (using smart transmitters)
is recommended for the LRRWTP.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
CHAPTER 2.0 REGULATORY REVIEW
2.1 PURPOSE
Since the original LRRWTP design was completed in 1991, there have been significant
regulatory changes in the design and operation of water treatment facilities. The City requested
that FNI review the existing and proposed drinking water regulations, risk management program
(RMP) requirements, Americans with Disabilities Act (ADA), the Uniform Fire Code (UFC) and
Uniform Building Code (UBC) requirements applicable to the LRRWTP and recommend design
modifications in meeting those regulations. This chapter reviews the requirements of the
existing and proposed drinking water regulations, RMP requirements and design criteria changes
for septic system design. The requirements of the ADA, UFC and UBC are discussed in Chapter
9.0, Administration Building.
2.2 EXISTING AND PROPOSED DRINKING WATER REGULATIONS.
The regulatory changes of the 1990's were the principal drivers of the design review and
produced the majority of the changes. Many of the regulations that were promulgated during the
1990 design still apply, such as the Total Trihalomethanes Rule, Surface Water Treatment Rule,
Total Coliform Rule, and the Lead and Copper Rule. Historically, the City has been in
compliance with all these at the Lake Lewisville Water Treatment Plant (Spencer Road WTP),
and the original design for the LRRWTP should not have any problems in complying with the
1990 regulations either. The recently proposed regulations that were not considered in the 1990
design and have caused this review are the Stage 1 Disinfectants and Disinfection By-Products
Rule (D/DBP), and the Interim Enhanced Surface Water Treatment Rule (IESWTR), both of
which are discussed in this chapter. A summary of all the relevant roles is shown in Table 2-1.
Disinfectants and Disinfection By-Products Rule (D/DBP) Stage 1
The D/DBP rule was proposed on July 29, 1994 and it was promulgated on December 16,
1998. The compliance date for larger water systems like the City of Denton (population greater
than 10,000) is set for January 1, 2002. The final D/DBP Rule addressed several complex and
interrelated issues. The intent of the rule is to balance the risk of acute health problems
associated with microbial disease outbreaks against the risks of chronic health problems
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
associated with disinfectants and their by-products. Disinfection by-products are formed when
disinfectants used for pathogen inactivation react with naturally-occurring organic matter found
in water.
The D/DBP Rule was proposed for promulgation in two stages. The intent of the first
stage was to provide a near-term, minimum level of regulation in regard to DBPs based on
existing health effects data. Although the second stage was proposed in 1994, it will be
renegotiated and revised following the collection of additional occurrence and treatment data
under the Information Collection Rule (ICR). Health effect studies and other research are also
expected to be completed for developing the Stage 2 requirements.
Requirements
Proposed new drinking water standards under the D/DBP Rule are shown in Table 2-1.
The term "Maximum Contaminant Level Goal," or MCLG, refers to a desired maximum
concentration that is calculated by a prescrib~ed EPA method based on health effects. These
goals are non-binding and indicate the concentrations below which there are no known health
effects. These values are generally below the corresponding MCLs for these compounds. The
term "Maximum Residual Disinfectant Level" or MRDL, has been newly created with the
release of the proposed D/DBP Rule. The MRDL requirements are similar to the MCL
requirements and the City must achieve an annual running average, computed quarterly, less than
the MRDL valuel
Stage 1 of the D/DBP rule also included a t~:eatment technique, known as enhanced
coagulation/softening, for removing certain percentages of total organic carbon (TOC), an
established indicator of DBP precursors. The objective of this requirement is to limit the
formation of both known and unknown DBPs. The level of TOC removal required will be based
on the source water alkalinity and initial TOC concentration as shown in Table 2-2. If a TOC
removal limit (Step I) cannot be met, the system will be allowed to conduct bench-scale tests to
determine an alternative site-specific limit (Step 11).
Systems can avoid enhanced coagulation/softening requirements if they meet one of the
following exemption criteria:
1) The system's source water TOC is less than 2.0 mg/L
2) The system's treated water TOC is less than 2.0 mg/L
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
3)
4
5
6
7
8).
The system's source water TOC less than 4.0 mg/L, its alkalinity greater than 60
mg/L (as CaCO3), and the system is achieving TTHMs less than 0.040 mg/L, and
HAA5 less than 0.030 mg/L (or the system has made a clear and irrevocable
financial commitment to technologies that will meet the TTHM and HAA level).
The system's TTHMs is less than 0.040 mg/L and HAA5 is less than 0.030 mg/L,
and when only chlorine is used as primary and secondary disinfectant.
The system's source water specific ultraviolet absorbance (SUVA) prior to any
treatment is less than or equal to 2 L/mg-m.
The system's treated water SUVA is less than or equal to 2 L/mg-m
For softening plants, remove magnesium hardness to at least' 10 mg/L as CaCO3.
For softening plants, lower alkalinity to less than 60 mg/L as CaCO3.
Raw water TOC data on Lake Ray Roberts- indicated that the LRRWTP would not meet
exception criteria No. 1 and No. 3 because raw water TOC is generally above 4.0 mg/L. The
finished water TOC data (generally above 2.0 mg/L) from the existing plant indicated that the
LRRWTP would probably not meet exception criteria No. 2. The TTHMs levels in the City's
distribution system were slightly above 0.05 mg/L. Therefore, the City would not meet exception
criteria No. 4. The raw water SUVA for the existing plant was generally above 2 L/mg-m. Since
the water quality for both Lake Lewisville and Lake Ray Roberts are sin'filar, it is likely that the
LRRWTP will not meet exception criteria No. 5 Jar testing indicated that the LRRWTP could
meet criteria No. 6, finished water SUVA, less than or equal to 2 L/mg-m, with a 20 mg/L alum
dose and 1.0 mg/L polymer dose. However, this test data would not be considered valid by the
TNRCC since the testing was done on raw water that had been pre-oxidized with KMn04. The
presence of an oxidant like KMn04 would cause interference in the SUVA measurement.
Discussions with the TNRCC indicated that the City most likely would be required to add
sufficient coagulant to meet the Step 1I TOC requirements (TOC removal at the point of
diminishing return) or provide alternate chemical treatment.
Compliance
The City of Denton should meet the D/DBP Stage 1 TTHM and HAA limits of 0.08 and
0.06 mg/L, respectively without modifications to the original design. However, the City's
LRRWTP would be required to remove at least 35 percent TOC (or Step 11 requirement) by
enhanced coagulation or other treatment processes unless the finished water SUVA exception
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
criteria are continuously met and accepted by the TNRCC. The City collected data over a week
at the existing plant while adding approximately 55 mg/L ferric sulfate. The TOC removal
varied from 27 to 34%, which is below the required 35%.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
Maximum C°fitaminant Level GOalS (MCLGs in mg/L)
Chloroform
Bromodichloromethane
Bromoform
Bromate
Dichloracetic acid
Trichloroacetic acid
Chlorite
0
0
0
0
0
0.3
0.8
Dibromochloromethane 0.06
Stage 1 Maximum Contarmnant Levels (MCLs in mg/L)
Total trihalomethanes (TTHMs) 0.080
Haloacetic acids (five) HAA5) 0.060
Bromate 0.010
Chlorite 1.0
(Not all compounds with MCLGs will have an
MCL established
Proposed stage 2 Maximum Contaminant Levelg (MCLs in rog/L)
TTHMs I 0.04
THAAs 0.03
Limits on Disinfectants (MRDLS in mg/L) ,~ ~
Chlorine I 4.0 (as C12)
Chloramines ~ I 4.0 (as total chlorine)
Chlorine dioxide 0.8 (as C 102)
Source Water Source Water Alkalinity (mg/L as CaC03)
TOC (mg/L)
0-60 >60-120 >120
>2-4 35 % 25% 15%
>4-8 45% 35% 25%
>8 50% 40% 30%
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
Interim Enhanced Surface Water Treatment Rule (IESWTR)
Requirements
Since the promulgation of the SWTR in 1989, several waterborne outbreaks of
cryptosporidiosis have occurred in the United States. The SWTR does not specifically address
Cryptosporidium. The degree of protection against this organism provided by the current SWTR
is uncertain. In the worst case, protection may be inadequate, particularly if a system is supplied
by poor-quality source water.
The IESWTR was finalized simultaneously with the D/DBP Rule on December 16,
1998. The compliance date of this rule was set on January 01, 2002. This interim rule applies
only to systems serving 10,000 people or more. The City of Denton falls into this group. The
IESWTR includes establishing an MCLG for Cryptosporidium, setting more stringent finished
water turbidity limits than currently required by the SWTR, and making no further changes to the
SWTR. Also, continuous monitoring of an individual filter is required by the IESWTR. The
more specific requirements of the IESWTR that might impact the City's water system are
summarized below:
1) Cryptosporidium MCLG: The IESWTR set a Cryptosporidium MCLG at zero.
2) Cryptosporidium log removal: All water systems that are required to filter must
achieve at least a 2-log removal of Cryptosporidium. Systems which use direct
filtration or conventional filtration treatment and meet turbidity requirements
described in the next paragraph (Item # 3) are assumed to achieve at least a 2-log
removal of Cryptosporidium.
3) Finished water turbidity performance requirements: The combined filtered water
turbidity must be less than or equal to 0.3 NTU in at least 95 percent of the
measurements taken per month and no turbidity measurements shall exceed a
maximum turbidity limit of 1.0 NTU.
4) Individual filter requirements: All water systems shall conduct continuous
monitoring of turbidity for each individual filter and shall provide an exception
report to the TNRCC on a monthly basis. The exception report shall include the
following: 1) any individual filter with a turbidity level greater than 1.0 NTU
based on two consecutive measurements fifteen minutes apart, and 2) any
individual filter with a turbidity level greater than 0.5 NTU at the end of the first
four hours of filter operation based on two consecutive measurements fifteen
minutes apart.
5) Disinfection profile development: Each public water system shall develop a
disinfection profile. The profile consists of a compilation of daily Giardia larnblia
log inactivations, or virus log inactivations where applicable, computed over the
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
period of one year. Systems would not be required to develop disinfection
profiles, if at least one of the following criteria are met.
a) TTHM levels are less than 80% of the Stage 1 D/DBP MCL (0.064 mg/L)
b) HAA5 levels are less than 80% of the Stage 1 D/DBP MCL (0.048 mg/L)
Compliance
With new filter design (either dual-media or deep bed mono-media) at the LRRWTP, the
City would be able to meet a fihished water turbidity of 0.3 NTU in 95% of the samples taken in
a month. To meet continuous turbidity monitoring requirements, an on-line turbidity meter will
be installed for each filter in the LRRWTP.
Regarding the disinfection profile development, the LRRWTP likely will not be required
to develop disinfection profiles since the current TTHM and HAA5 levels are below the 80%
levels of their Stage 1 D/DBP MCLs.
2.3 ANTICIPATED FUTURE DRINKING WATER REGULATIONS
New drinking water regulations will continue to develop as required by the 1986 and
1996 amendments to the federal Safe Drinking Water Act. The primary focus of these
regulations is to reduce the levels of microbiological pathogens and disinfection by-products in
water delivered to system customers. By the very nature of the regulations, water suppliers like
the City of Denton using surface water sources will be required to modify, and in some cases,
upgrade treatment unit processes.
This section of the memorandum will present the proposed requirements of the
regulations and the City of Denton's ability to comply with these proposed requirements will be
discussed.
Long-term (Stage 2) D/DBP Rule
Stage 2 of the D/DBP role proposes to further reduce drinking water standards, or MCLs,
for D/DBPs. New D/DBP standards will be proposed under Stage 2 if it is determined that
treatment techniques such as enhanced coagulation/softening, alone or in combination with
reduced or alternative application of disinfectants, can be implemented without increasing the
risk from microbiological constituents. As noted above, information developed during the ICR
will be used to develop additional requirements, if any, for the Stage 2 rule.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
Requirements
As currently proposed, the MCLs for TTHMs and THAAs would be reduced to 0.040
mg/L and 0.030 mg/L, respectively.
Compliance
The current annual average TTHM level for the City's distribution system is slightly
above 0.05 mg/L. Therefore, the City of Denton is not likely to meet the Stage 2 D/DBP limits
for TTHMs if the current disinfection strategy used in the existing plant is installed in the
LRRWTP.
Compliance Schedule
Stage 2 of the D/DBP role is scheduled to be proposed in November 2000 for
promulgation within two years. The compliance date for the City of Denton would likely be
within three years after the rule promulgation, probably in the year 2004 or 2005.
Long-term (Stage 1 & 2) Enhanced Surface Water Treatment Rule (LTESWTR)
A long-term Enhanced Surface Water Treatment Rule (LTESWTR) is under
development. Stage 1 (LT1ESWTR) is similar to the current regulation (IESWTR) and basically
extends the requirements of the IESWTR to water systems serving less than 10,000 people. It is
expected to be finalized by August 2000. Stage 2 (LT2ESWTR) is expected to include
additional requirements such as backwash water recycling and filter-to-waste issues that would
be applicable to the larger water systems, including the City of Denton. The proposed and final
rules for the LT2ESWTR are expected February 2001 and May 2002, respectively.
Requirements
The City of Denton may be required to treat filter backwash water prior to recycling and
have filter-to-waste capability.
Compliance
It is recommended that the City install an air scour backwash system in the LRRWTP.
Air scour backwash has been demonstrated to consistently produce a cleaner and more uniformly
cleaned filter media at the completion of the backwash cycle. Additionally, by adding an air
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
scour backwash system, the City will reduce backwash water volume by 20 to 30%, thus
reducing the capital and operating costs for backwash water treatment (if required). The filter
design will include filter-to-waste capability.
Compliance Schedule
If this rule is promulgated as scheduled, the City will be required to meet the
requirements by November 2003.
Table 2-3 summarizes the regulations that have been discussed in this chapter. The
information contained in this table for the proposed regulations is current as of October 1999.
Due to the preliminary nature of these rules and changing political climates in the Federal
government, these rules may be significantly different when finalized. Nevertheless, the City
will likely encounter increasingly complex regulatory requirements in the future relative to
microbial removals and disinfection by-products.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
Table 2-3 - Existing and Proposed Regulatory Requirements, Summary
City of Denton
Trihalomethanes Nov. 29, 1979 Active; Proposed D/DBP Rule Set an MCL of 0.100 mg/L for sum
would revise this regulation total of four trihalomethanes. Based on
an annual average of running quarterly
values.
SWTR June29, 1989 Active; Proposed ESWTR Required filtered water turbidities of
May increase requirements for less than 0.50 NTU 95 pement of the
microbial removal, time in any month. Required 3-log and
4-log removal of Giardia and viruses
through treatment and disinfection.
Required minimum disinfectant
residual be maintained in distribution
system.
TCR June 29, 1989 Active Requires sampling for total coliforms in
the distribution system. No more than
one sample may be total coliform
positive.
LCR June7,1991 Active Established monitoring requirements
and "action level" concentrations of
0.015 and 1.3 mg/L for lead and
copper, respectively. Concentrations
are measured at consumers' taps.
Stage 1 D/DBP July 29, 1994 Active Increased the number of DBPs
Rule regulated and set standards for
maximum levels for chlorine-based
disinfections in Stage 1.
IESWTR July29, 1994 Active MCLG for Cryptosporidium is set at
zero. New levels of inactivation for
Cryptosporidium. Reduced finished
water turbidity requirements to 0.3
NTU in 95% measurements per month.
Continuous monitoring of filters is
required. Development of disinfection
by-product profiles is required.
~,~ Prop,s ~ ~
Stage 2 Proposed Rule is scheduled Will set lower MCLs for DBPs than the
D/DBP Rule for November 2000. MCLs set under Stage 1
Final Rule is scheduled for
May 2002.
LTF-,$WTR Proposed Rule is scheduled Will set requirements for treating and
for November 1999. recycling filter backwash water and
Final Rule is scheduled for have provisions for filter-to-waste.
November 2000.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
2.4 RISK MANAGEMENT PROGRAM (RMP)
The Risk Management Program (RMP) was created as part of the Clean Air Act
Amendments of 1996. The program focuses on preventive measures to reduce the likelihood of
accidental releases of chemicals such as chlorine. Facilities with more than a threshold quantity
of any specifically listed chemical are required to develop and implement a Risk Management
Program. The Clean Air Act (CAA) of 1996 states that facilities have a "general duty ...to
identify hazards which may result from such releases using appropriate hazard assessment
techniques, to design and maintain a safe facility taking such steps as are necessary to prevent
releases, and to minimize the consequences of accidental releases which do occur."
[CAA{} 1129(0(I)]
The RMP rules require the following actions to be undertaken:
identification of management officials responsible for the implementation of the RMP
(management system);
an inventory of significant previous releases involving regulated chemicals (five-year
accident history);
an off-site consequence analysis, which estimates the potential affected area of accidental
releases (worst-case scenario and alternative release scenario);
development and documentation of safety systems (prevention program);
development of an emergency response program; and
submission of a Risk Management Plan to Environmental Protection Agency (EPA) on or
before regulated chemical is first present at or above its threshold quantity.
The RMP has three prevention program levels; Program 1, Program 2, and Program 3.
Water Treatment plants in the State of Texas owned and operated by state or local governments,
such as municipalities, are likely subject to Prevention Program 2. If worst-case release scenario
shows no public receptors within impact area, plant may be subject to Prevention Program 1.
Program 3 is for heavy industry and states that have adopted OSHA Process Safety Management
requirements for public employers. In the state of Texas water treatment plants are not subject to
prevention Program 3.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
The Risk Management Plan (RM Plan) is a summary of the RMP, and must be submitted
to EPA on electronic diskette. All elements of the RM Plan are available to the public on the
Intemet, except for the off-site consequence analysis (OCA) information, which is publicly
accessible in hard copy format. The Federal government is currently conducting an assessment
and will issue regulations governing future public access to OCA data. Until then, the plant will
likely be required to conduct a public meeting summarizing the RMP.
The City of Denton Surface Water Treatment Plant provides treated water to residential,
commercial and industrial sectors of th.e City. Raw water is processed and treated with chlorine
and ammonia in the treatment process.
It is common practice to size the chlorine bulk storage tank to equal the standard load
delivered from the supplier. This is done to minimize the risk of overfilling. Therefore, the
LRRWTP will maintain a maximum inventory of 25 tons of chlorine. The 25 tons is above the
2,500 pounds RMP threshold value. As a result, the LRRWTP must develop the RMP and
submit a R_M Plan to the EPA before chlorine is present at the plant in quantities exceeding 2,500
pounds. Only approximately 4 tons of anhydrous ammonia will be stored at the plant. It is
common for ammonia bulk tanks to be specified/constructed to match the feed requirements as
opposed to sizing to match the delivery track load, as the risks for overfilling are less than for
chlorine. This is below the 10,000 pounds RMP threshold for anhydrous ammonia. As a result,
the LRRWTP would not have to submit a RM Plan for anhydrous ammonia.
The prevention program for Program 2 contains the following elements:
Process Safety Information: Compilation of all safety related information for each process
involving a regulated substance.
Hazard Review: Documented comprehensive review of all processes involving regulated
chemicals which follow an organized checklist developed for each regulated process. The
review must be updated at least once every five Years or when there is a major change in the
process.
Operating Procedures: Written procedures which describe what tasks an operator must
perform when working on a regulated process.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Regulatory Review
Operator Training Program: Documented records which illustrate that each employee
working on a regulated process has received the proper operational and safety training.
Mechanical Integrity (Maintenance): Written maintenance schedules and procedures for
ail regulated processes.
Compliance Audits: Documentation that the prevention program has been periodically
reviewed to assure accuracy and up-to-date information on all aspects of the program. A
compliance audit must be performed at least every three years.
Incident Investigation: Written summary of any accident involving, regulated process,
including recommendation and actions to prevent future incidents.
2.5 SEPTIC SYSTEM DESIGN CRITERIA REVISION
FNI contacted the Denton County Health Department (DCHD) and obtained the updated
design criteria for septic system design. Most of the design criteria effective in 1991 are still
valid. Additional criteria have been added in the septic tank design, which are presented in Table
2-4. The design of the existing septic system will be modified to comply with the current design
criteria. The system will be designed as an evapotransporation bed system due to the likelihood
that the City will recycle the groundwater collected from the plants dewatering wells. The ET
beds will have a suitable liner system to prevent possible introduction of the effluent into the
groundwater. For more details on this discussion refer to Technical Memorandum No.1, "Safe
Drinking Water Acts Regulatory Review" in the Appendix.
1. For septic tanks, the entry point of the outlet device shall be below the liquid level of the tank at a
depth between 25 to 50% of the overall liquid depth of the tank
2. For septic tank cleanout ports, the openings smallest dimension shall be not less than 12 inches
3. All precast septic tanks shall be marked with manufacturer's name, address and tank capacity.
4. Septic tanks must be installed so as to provide at least 12 inches of drop in. elevation from the
bottom of the outlet pipe to the bottom of the disposal area.
5. For evapotranspirative drainfield, backfill material shall consist of soil Class II.
6. The porous media of evapotranspirative drainfield shall extend at least one foot beyond the edge of
the drainline horizontally.
7. The evapotranspirative drainfield shall be divided into two or more separate units connected by
flow control valves.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
CHAPTER 3.0 ALTERNATIVE CHEMICAL TREATMENT
EVALUATION (OZONE)
3.1 PURPOSE
Since 1991, when the initial design of the LRRWTP was completed, there have been
significant regulatory changes and changes in the design, technology and standard practice of
operation of water treatment facilities. The City requested that FNI review the changes in the
regulations and technology and recommend necessary design modifications.
A principal area explored was the basic chemical treatment process-coagulation using
ferric sulfate. Promulgated regulations would require the plant to operate in enhanced
coagulation mode, increasing the cost of operation and possibly making turbidity removal more
difficult. Ozonation for conditioning of water and disinfection was also identified as a candidate
process to comply with the regulations. Ozonation involves a high capital cost but can offer
reduction in operating costs and would produce a higher quality finished water.
The purpose of this chapter is to present the results of the enhanced coagulation jar
testing and develop a compliance plan with respect to the total organic carbon (TOC) removal
requirements of the Stage I Disinfectants/Disinfection By-product (D/DBP) role. Also, an
economic analysis of enhanced coagulation and ozonation processes is presented in this chapter.
3.2 REGULATORY REQUIREMENTS AND ALTERNATIVE EVALUATIONS
Stage 1 of the D/DBP rule was promulgated on December 16, 1998 and it will be
effective on January 01, 2002, prior to the projected summer 2002 start-up date for the
LRRWTP. It sets the MCL's for TTHM's and HAA5 at 0.03 and 0.06 mgfl, respectively. An
additional requirement of this rule is a specific TOC removal requirement by the treatment
process. This TOC removal requirement is dependant on the raw water TOC and alkalinity
levels. If a TOC removal limit (Step I) cannot be met, the system will be allowed to conduct
bench-scale tests to determine an alternative site-specific limit (Step ID.
Stage 2 of the D/DBP Rule will most likely lower the MCL's for TTHM's and HAAS to
0.04 and 0.03 mg/L, respectively. The role is reportedly to be finalized in May 2002. Historical
difficulties in arriving at consensus on a rule of this magnitude and discussions with members of
3-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
the task fome working on the Rule suggests that it likely will be the year 2004/05 before the role
is promulgated, and another 36 months before it is effective.
Stage 1 D/DBP Compliance
Historical operating data at the DWU's Lake Lewisville WTP and jar test results on Lake
Ray Roberts raw water suggest that the City will be able to comply with the Stage 1 TTHM and
HAA5 MCL's by following current operating practices. Compliance with the Step I and I1 TOC
reduction requirements of the Stage 1 D/DBP was the more difficult to achieve parameter and
was shown to be the governing parameter, requiring operation in the Enhanced Coagulation
mode or some alternate form of treatment.
Recent water analyses from Lake Ray Roberts show that TOC and alkalinity levels in the
raw water are 4 to 8 mg/L and 60 to 120 mg/L (as CaCO3), respectively. Based on this raw
water quality, Step I would require the LRRWTP to remove at least 35% TOC. Step II, if
necessary, requires removal to the percentage set at the point of diminishing return (PODR). The
PODR is defined as the point on the TOC versus coagulant dose plot where the slope changes
from greater than 0.03 mg/L TOC/mg/L Coagulant to less than 0.03 mg/L XOC/mg/L Coagulant and remains less
than 0.03.
The best available technology to achieve either the Step I or Step 11 TOC removal
requirements is enhanced coagulation. Enhanced coagulation is defined as the process of
obtaining additional TOC removal by adding increased amounts of coagulant. Enhanced
coagulation is not required for the LRRWTP if the plant can meet one of the six exception
criteria discussed in Chapter 2.0. The City of Denton demonstrated through jar testing that they
could meet the criteria for exception No. 6 which requires treated water specific ultraviolet light
absorbance (SUVA) to be less than or equal to 2 L/mg-m. However, this test data would not be
considered valid by the TNRCC since the testing was done on raw water that had been pre-
oxidized with KMn04. The presence of an oxidant like KIVIn04 would cause interference in the
SUVA measurement. Preliminary discussions with the TNRCC indicate that the TNRCC would
require DWU to meet the Step. 11 TOC requirements instead of allowing the utility to avoid
enhanced coagulation by meeting exception criteria No. 6. Therefore, Enhanced Coagulation or
some other form of treatment would be required.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
Enhanced Coagulation Jar Tests were conducted using raw water from Lake Ray Roberts
to determine the enhanced coagulation dosage for removing at least 35% raw water TOC (Step I)
and to detemdne the ferric sulfate dose to reach the PODR (Step I~.
The jar testing indicated that the Lake Ray Roberts water was recalcitrant and would not
be able to meet the 35% removal requirement. The Step 11 PODR-TOC removal will govern the
dosage requirement for the LRRWTP. The jar testing demonstrated that the LRRWTP could
meet the Stage 1 D/DBP Rule if operated in the PODR Enhanced Coagulation mode. The PODR
dosage of 42 mg/1 of ferric sulfate yielded a TOC reduction of 23.9%. These would be the
values assumed for Enhanced Coagulation for any treatment alternative comparisons, or for
preliminary design.
Stage 2 D/DBP Compliance
Historical operating data at the DWU's Lake Lewisville WTP and jar test' results on Lake
Ray Roberts raw water suggest that the City will not be able to comply with the Stage 2 D/DBP
Rule as currently proposed. A treatment process other than enhanced coagulation will be
required to meet the proposed regulations.
Ozone Treatment Process
An alternative to enhanced coagulation in meeting the TOC removal requirement is
ozonation with biologically active filtration, also referred to as biofiltration. Ozone has been
shown to break down high molecular weight TOC into smaller molecular weight TOC which can
subsequently be assimilated by microorganisms attached to the filter media (biofiltration). The
oxygen rich water created by the normal breakdown of ozone into molecular oxygen and the
abundant supply of easily assimilated organics in the ozonated water create an ideal environment
for the microorganisms. Without ozone, biofiltration would not occur in the filters. More
effective biological filtration is obtained with granular activated carbon filters using (GAC)
media than in filters using either sand or anthracit~ media due to the greater surface area and the
adsorptive properties of GAC. However, to accomplish the required turbidity removal, a deeper
bed depth of GAC media is needed than would be required with sand or anthracite mono or dual
media.
Ozone also serves as the primary disinfectant. This eliminates the use of free chlorine as
a primary disinfectant, under normal operating conditions, to comply with the CT requirements
3-3
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
of the SWTR. However, the secondary disinfectant, chloramine, still would continue to be used.
By eliminating free chlorine usage, the LRRWTP will increase the likelihood of complying with
the Stage 2 D/DBP limits for TTHMs and HAA5 of 40 and 30 ug/L, respectively.
Ozone, a powerful oxidant, is being applied more frequently as a primary disinfectant in
water treatment plants in the United States. It offers an additional benefit of reducing taste and
odor in the finished water. Adding ozone in raw water will eliminate potassium permanganate
and/or powdered activated carbon (PAC) usage at the LRRWTP.
Experience at other plants in this region suggests pre-ozonation will reduce coagulation
chemical usage by 30 to 50%. Intermediate ozonation acts as a filter aid by agglomerating
particles in the settled water. Overall, ozonation (pre plus intermediate ozonation) dramatically
improves finished water quality as measured by TOC and turbidity removal.
A disadvantage of ozone is the formation of bromate which will be regulated at 10 ~tg/L
level by the Stage 1 D/DBP role. Experience with raw water quality in the North Central Texas
area indicates that bromate formation in the LRRWTP is not likely to exceed the regulatory limit.
However, baseline bromide data for Lake Ray Roberts will be necessary to predict the specific
bromide formation.
Montgomery Watson America conducted bench-scale and pilot plant studies for the
Upper Trinity Regional Water District using Lake Lewisville Water, which is similar in quality
to Lake Ray Roberts. The report concluded that treatment using ozone would be able to comply
with the bromate MCL without pH adjustments or other bromate control techniques.
The City of Dallas, Texas, Elm Fork WTP also treats Lake Lewisville water with pre-
ozonation, and has not reported elevated bromate concentrations.
With ozonation and deep bed filters using GAC media, the LRRWTP should meet the
Stage 1 and 2 TTHM and HAAS MCL's as well as the Stage 1 D/DBP TOC removal
requirement.
3.3
ECONOMIC ANALYSIS BETWEEN ENHANCED COAGULATION AND
OZONE TREATMENT ALTERNATIVES.
The historical operating data at the DWU Lake Lewisville WTP, jar tests performed on
the Ray Roberts water by Freese and Nichols, and pilot scale treatability testing by others on
similar North Central Texas raw waters suggest that the LRRWTP will be able to comply with
3-4
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
the Stage 1 D/DBP Rule by operating in the PODR Enhanced Coagulation mode of operation,
but will not be able to comply with the Stage 2 D/DBP Rule without going to an alternative
mode of treatment, such as ozonation. The alternative treatment facilities could be constructed
as part of the initial construction of the LRRWTP or delayed to coincide with the anticipated
start date of the Stage 2 Rule
According to best available information, the proposed Stage 2 rule will be promulgated as
proposed, in the 2004-05 time frame and will become effective sometime during the years 2007-
08. Since the timeline for adoption of the Stage 2 rule occurs near the anticipated completion
timeline of the initial construction of the LRRWTP (2002-03) it was appropriate to consider two
scenarios for implementing the alternate treatment/disinfection economic evaluation process.
The first scenario phases the construction of the ozone facilities to coincide with the Stage 1 and
Stage 2 rule implementation schedule. This scenario would initially employ Enhanced
Coagulation for TOC and turbidity removal and chlorination as the primary disinfectant with
ozone disinfection facilities added in year 2006.
The second scenario included ozone facilities as part of the initial LRRWTP
construction. The capital and annual costs of both alternatives were calculated and a life cycle
cost analysis was done on a 20 year and a 50 year basis. The 20 year analysis is the industry
standard for projects of this type. It generates costs that are comparable to the total project cost
projections made for the other components of the LRRWTP. The 50 year analysis was prepared
to deter'mine the sensitivity of the analysis with respect to the assumption made on the when the
Stage 2 Rule would be promulgated.
The analysis indicated that constructing the ozone facilities as part of the initial
construction as opposed to deferring the construction of the ozone facilities until 2006 would
result in a savings of $187,000/yr for each year of the 20 year planning period. To determine
how closely this result was tied to the assumed timeline of rule promulgation in 2004-05, a cost
sensitivity analysis was performed to determine at what point the savings would disappear. The
required timeline for promulgation of the Stage 2 rule would have to be delayed in excess of 30
years for the economics to favor deferring the construction. The detailed alternative cost
analysis is included in the Appendix.
3-5
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
3.4 RECOMMENDATION
FNI recommend that the city include ozonation facilities in the initial construction of the
plant. It is recommended that some specific Lake Ray Roberts pilot scale treatability tests be
performed during the Spring/Summer of 2000 to establish the optimal ozone configuration
(intermediate ozonation only, or pre-ozonation with intermediate ozonation) and the design
parameters. Intermediate ozonation only will produce the required treatment and will involve
less construction. The addition of pre-ozonation involves additional construction cost but will
reduce the overall chemical requirements. Operational data at ozone plants in North Central
Texas showed that ozone addition in the raw water reduced primary coagulant chemicals by 30
to 50%. Table 3.1 estimates the potential chemical savings on the LRRWTP at $285,000 over the
first 20 years of operation.
The ozonation facilities as proposed include preozonation contactors, intermediate
ozonation contactors, a liquid oxygen storage tank, ozone generators, ozone destruct equipment,
a building to house ozone generation equipment, and instrumentation and control. The
intermediate ozone contactors (ozone contactors between the sedimentation basins and filters)
will be used to meet primary disinfection requirements and to control taste and odor. The
preozonation contactors will be used to add ozone in the raw water in achieving
microflocculation benefits of ozonation. The size of a preozonation contactor is generally one
half the size of an intermediate ozone contactor. The ozone dose in the preozonation contactors is
low as compared to the ozone dose in the intermediate contactors. The preozonation dose is
normally twenty percent (20%) of the total ozone dose (ozone demand). The proposed ozone
facilities are shown in Figures 3.1, 3.2 and 3.3. For plant layout and construction budgeting
purposes, we have assumed the inclusion of pre and intermediate ozone facilities. The ultimate
configuration will be detemfined from both the results of the pilot testing and input during a
design workshop during the design phase.
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MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
TABLE 3-1
Estimate of Chemical Cost Savings
with Pre-Ozonation
If we assume thirty percent (30%) reduction of ferric sulfate and caustic due to ozone
addition for the LRRWTP, the City will save a total chemical cost of approximately $285,000
over a 20-year period. The calculations are as follows:
Design average ferric sulfate dose = 12 mg/L
Design average caustic dose = 4.8 mg/L
Average flow = 16 MGD
Ferric sulfate unit cost = $92.0/Ton
Caustic unit cost = $175/Ton
Total ferric sulfate usage for
20 years =12 mg/L*8.34 Ib/MG* 16 MGD*365 days/yr*20 yr/(2000 lb/Ton)
= 5845 Tons
Total ferric sulfate savings (30%) due to
preozonation = 5845 Tons * (30/100) * $92/Ton
= $162,000
Total caustic usage for 20
years = 4.8 mg/L*8.34 Ib/MG*16 MGD*365 days/yr*20 yr/(2000 lb/Ton)
= 2338 Tons
Total caustic savings (30%) due to
preozonation -- 2338 Tons * (30/100) * $175/Ton
= $123,000
Total Savings in Chemical Costs = $285,000
3-7
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Alternative Chemical Treatment Evaluation (Ozone)
CHAPTER 4.0 RAW WATER SPLITTING AND CHEMICAL MIXING
4.1 PURPOSE
Flow splitting was not included in the initial design since there was only one 10 MGD
train to be constructed. Since the modified plant's rated capacity will be 20 MGD with two 10
MGD trains, a means of splitting flow to each treatment train would need to be constructed. The
rapid mix system/chemical addition design was also reviewed.
Three rapid mix/flow splitting system alternatives with the most apparent application for
the LRRWTP were selected for evaluation.
4.2 RAPID MIX SYSTEM/FLOW SPLITTING OPTIONS
Complete and instantaneous dispersion of chemical coagulants is required to achieve
optimum coagulation and minimize chemical costs. Conventional mixing design provides for 30
to 60 seconds detention time with a velocity gradient of 500 to 1500 sec 4. More recent
applications suggest near instantaneous mixing of 0.5 seconds with a velocity gradient of at least
1000 sec '~
The flow splitting alternatives need to have the flexibility to allow the flow to split into
two trains during the initial construction, and up to five trains by the time it reaches the 50 MGD
capacity. When using mechanical mixing, redundancy is required by the state design criteria.
The analyzed alternatives were:
Alternative A.-
Pumped diffusion and rate-of-flow control valves. This alternative requires additional
space between the chemical tank storage area and the flocculation basins to allow for adequate
upstream conditions prior to the flow meters in each meter vault. This will require adjustments to
the site plan, paving, and drainage. The pumped diffusion requires one 15-HP pump operated
continuously. The opinion of probable construction cost for this alternative is $486,000 at 20
MGD and $838,000 at 50 MGD.
4-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Ground Water Control
Alternative B.-
Pumped diffusion and splitter box. For the initial 20 MGD plant design, only a portion of
the structure would need to be constructed. This alternative utilizes the pumped diffusion vault
for rapid mixing and chemical addition. This alternative requires continuous operation of one 15
HP pump. The opinion of probable construction cost for this alternative is $329,000 at 20 MGD
and $503,000 at 50 MGD.
Alternative C.-
Rapid mix structure with mechanical mixing and splitter box. As discussed for
Alternative B, only a portion of the splitter box would need to be constructed for the initial 20
MGD plant. This alternative requires continuous operation of one 25 HP mixer for the 20 MGD
plant. When the plant is expanded, two 25 HP mixers will be operated continuously. The
probable construction cost for this alternative is $368,000 at 20 MGD and $545,000 at 50 MGD.
4.3 RECOMMENDATION
The pumped diffusion system, the mixing alternative considered in the original design, is
the recommended chemical mixing alternative. The primary coagulant is added to the discharge
side of a pump and then injected countereurrent to the raw water flow through a high velocity
nozzle. This provides an intense mixing zone in which rapid dispersion of the coagulant occurs.
Different treatment plants using the system were contacted to detemtine operational history of
the system. Some of the advantages mentioned were cleanness, silence, chemical savings and
low maintenance. The disadvantages mentioned were low flexibility, lack of experience using
ferric sulfate and nozzle clogging. Therefore, spare feed taps upstream of the nozzle and
provisions for removal of the nozzle without taking the raw water pipeline out of service will be
provided.
Because of its economic advantage, the splitter box flow splitting alternative is
recommended. The structure will be designed to uniformly distribute velocity gradients across
the basin. The initial construction will include the required structure for two trains. The splitter
box will be expanded when more treatment trains are added in the future. The proposed splitter
box is shown in Figure 4-1.
For more details on this discussion refer to Technical Memorandum No.3 "Rapid Mix
and Flow Slitting Evaluation" in the Appendix.
4-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Ground Water Control
CHAPTER 5.0 GROUND WATER CONTROL
5.1 PURPOSE
Lake Ray Roberts filled rapidly as the original plant design was being completed in 1990.
This filling of the lake impacted the groundwater conditions at the LRRWTP site. The City
installed piezometers in the early 90's and has been monitoring groundwater levels at the
LRRWTP site. Initial piezometer readings in 1990/91 indicated groundwater levels ranging
from El. +582 feet to El. +592 feet. The ground surface elevation a the site is approximately El.
+598 feet. The geotechnical report prepared in 1990 to account .for higher than anticipated
groundwater levels recommended using an assumed groundwater level of El. +595 feet for
structural design relative to uplift pressures and lateral wall pressures. More recent (1998/99)
piezometer readings indicate groundwater levels of El. +582.42 feet to El. +592.82 feet
suggesting the impact of the lake on the groundwater at the plant is permanent.
The original and current plant designs included foundations with depths that range from
approximately 5 to 25 feet below the groundwater level, as shown previously in Figure ES-2,
Modified Hydraulic Profile. This situation presented a threat to the treated water quality through
infiltration of the groundwater and to the structures themselves, indicating that structural
facilities to mitigate the impact of the groundwater were needed.
5.2 GROUNDWATER MITIGATION ALTERNATIVES
In the current preliminary design study different alternatives were studied to mitigate the
impact of high groundwater levels. These alternatives were:
· Place an intermediate pump station using vertical propeller pumps between the filters and
clearwell to allow the clearwell structure to be raised above the groundwater.
· Place an intermediate pump station using screw pumps between the filters and the
clearwell, for the same purpose.
· Both previous options, placed between sedimentation basins and the filters, raising both
the filters and clearwell.
· Installing dewatering wells next to the impacted units.
· Soil bentonite barrier installed with a slurry trench cutoff
· Grout curtain installed with high pressure grout methods.
· Installing a vinyl sheeting barrier
· Installing a permanent dewatering interceptor trench.
5-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Ground Water Control
5.3 RECOMMENDATION
The soil bentonite barrier with intermittent dewatering alternative was the lowest cost and
most reliable approach to minimize the exposure of the treatment units to the groundwater, as
shown in the December 15, 1999 memorandum - "Dewatering Alternatives for the Proposal
Clearwell Area" included in the Appendix.
A permeability of 1.0xl0-7 can be achieved with this system. The wall will be 1680 feet
long, surrounding the filters, washwater reclamation basin, main drain pump station, and transfer
pump station. The trench wall is shown in Figure 5.1. The trench will be deep enough to
intersect the top of the weathered shale located 37 feet below ground. Dewatering wells will be
placed inside the barrier walls.
Initial dewatering will drop the water level down to safe levels for the construction and
operation of the units. After this, only minimal, intermittent dewatering will be necessary.
5-2
(;ND.
WATER ·
EL..+590
EXISTING
SOIL
APPROX.
:'IN.
(;RADE
EL.+598
FT(+)
TRANSFER
PUMP
I
I
I
WEATHERED
SHALE
SECTION
1 "=20'
FLOW
METER
FUT. WASHWATER
RECL.
FREESE o
WASHWATER
BASIN
SLURRY TRENCH
WALL
MAIN DRAIN SUMP
0 50' 100'
1 "=100'
F,~N aol~ I~r~9947§
CITY OF DENTON, TEXAS
RLE FI0--5-- 1 .OWG
D~'~ RUARY 2000
SCALE
AS SHOWN
SLURRY TRENCH WALL LAYOUT
DRAFTED
SB
200'
5-1
FIGURE
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Filter Design
CHAPTER 6.0 FILTER DESIGN
6.1 PURPOSE
Significant advances have occurred in filter technology since 1991. The original design
is to be modified to take advantage of these advances. Also, some additional changes are needed
to optimize the benefits of the added upstream ozone process and to comply with new
regulations. These changes relate to the type of filter media used. Filter to waste provisions also
are to be included.
6.2 ALTERNATIVE CONFIGURATIONS
Three different layouts were presented together with their corresponding advantages and
disadvantages. The alternative descriptions are included in the Appendix. These options
included:
Original Layout
Cluster Arrangement Layout
· Conventional Arrangement Layout
The recommendation of FNI and the decision of the City was to remain with the original design.
6.3 RECOMMENDATION
The recommended alternative is to maintain the basic configuration of the gravity sand
filters as originally designed. These are Self Backwashing Filters with influent controlled by a
downward opening weir and the effluent controlled by a Set level in the transfer pump station
wetwell. The level in the wetwell will be set by plant staff and maintained by the variable speed
pumps in the transfer pump station. A back-up system for controlling the set level via a motor
operated weir gate will also be considered during the design phase.
Minor modifications to the initial design are recommended, such as a change of the
media to GAC mono-media over a 6-inch thick sand cushion to take advantage of the ozone
process and to comply with future regulations. The GAC media following ozonation has a
demonstrated ability for effective removal of TOC. The deep depth of the GAC and the added
sand cushion will provide the required turbidity removal. The underdrain ~y~tem will have air
scour backwashing capabilities for more effective cleaning of the media. The design also
6-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Filter Design
includes filter to waste provisions, in-line turbidity meters and particle counters to minimize and
monitor turbidity spikes in the filter effluent.
There initially would be 8 filters with a total capacity of 25 MGD. Design elements are
explained in Table 6-1 and shown in Figures 6-1, 6-2, and 6-3.
For more details on this discussion, refer to Technical Memorandum, "Gravity Sand
Filter Alternatives" in the Appendix.
6~2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Filter Design
Table 6-1
Filter Design Parameters
Media
Backwash
Parameter
Mode of Operation Capacity
Filter to Waste
Advantages
Disadvantages
Design
44" GAC over 6" sand cushion
1/d~0 greater than 1250
Air over Water Backwash Programmable for
Collapse Pulsing Bed Backwash
3-5 scfm/sf air blower design
15 gpm/sf water backwash design
Constant Rate influent controlled
Total Capacity
One Filter off-line
Two Filters off-line
25 MGD
21.9 MGD
18.75 MGD
Individual lines off the filter effluent that will
require widening access corridor
Duplex submersible pump station return with
routing to sedimentation basin effluent channel or
downstream of pump diffusion
Gravity flow to Washwater Reclamation Basin
Maximizes use of original design
High level of reserve capacity with filters off-line
Moderate cost
Minimal O&M through self backwashing feature
- Separate influent and effluent pipe access areas
- Deep construction
- Major redesign to accommodate different mode of
filter operations
6-3
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
High Service Pump Station and Storage
CHAPTER 7.0 HIGH SERVICE PUMP STATION AND STORAGE
7.1 BACKGROUND
The original concept for the development of the LRRWTP was to have most of the water
storage at the Hartlee Field Road Pump Station (HFRPS). The major reason for developing this
concept in 1990 was that the LRRWTP was intended as a regional water treatment plant, and that
the wholesale customers would provide their own storage to meet peak demands. Now, the
LRRWTP is intended to serve only the City of Denton. A study was performed by FNI
comparing the costs of locating the high service pump station and storage tanks at the HFRPS
and LRRWTP sites. The results of this study are found in a memo dated January 8, 2000. In this
study, FNI recommended eliminating the HFRPS and locating the 60 MGD high service pump
station at the LRRWTP site. The revised concept was approved by the City of Denton.
7.2 STORAGE TANKS
The revised concept will have a transfer pump station after the filters that will allow
clearwell storage to be above ground. One 6 MG tank will be constructed initially with room for
five additional 6 MG tanks. FNI will evaluate prestressed concrete tanks and welded steel tanks,
taking into account the life-cycle costs, foundation considerations, construction cost, and the
experience of city personnel.' Our previous cost estimates have assumed pre-stressed concrete
tanks will be used.
Freese & Nichols will investigate using an aluminum dome as a roof for the storage
tanks. The aluminum dome has several advantages including lower cost, higher corrosion
resistance, and lower weight that will lessen the soil bearing load. We recommend the following
appurtenances be installed for the new 6 MG tank:
· Inlet and outlet piping and isolation valves
· Overflow piping with erosion protection and air-break
· Tank drain line and air break off the tank discharge
· Painted exterior ladder with safety cage
· Stainless steel interior ladder with safety cage
· Roof ladders for access to vents and manholes
· 1-30" diameter roof access manhole
· 3-30" screened roof vents
· 2-30" shell manholes with davits
7-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
High Service Pump Station and Storage
· Lightning protection
· Exterior lighting
· 4-20 mA level transmitter with indicator inside the pump station
· Low level and high level cut-off switches
7.3 PUMP STATION LAYOUT
The pump station will be designed for an initial firm capacity of 30 MGD and a future
firm capacity of 60 MGD. The pump station will be constructed with approximately six pump
slots. The preliminary selection includes four pumps initially, three 14 MGD pumps and one 6
MGD pump. Two 14 MGD pumps could be installed at a later date to bring the firm capacity to
62 MGD. The number of pumps and the sizes will be re-evaluated during the final design phase.
The smaller pump will have a low voltage variable frequency drive to allow for greater pumping
flexibility. The type of starters will be verified after coordination with the electric utility. For
the purpose of this report, we have assumed that each pump will have a soft starter to minimize
electrical in-rush.
FNI will evaluate canned vertical pumps and horizontal split-case pumps. Horizontal
pumps not~xially provide higher efficiency and lower maintenance costs; however, vertical
pumps allow a wider range of suction and discharge head conditions. The type of pumps will be
selected after the head conditions are verified.
Figures 7-1 and 7-2 show the preliminary layout and section for the high service pump
station. The typical section illustrates that the six suction lines will diverge from the header.
Gate valves will be used for isolation of the suction lines. A flexible, harnessed dresser coupling
will be provided to allow for easy pump removal. A pump control valve will be used to reduce
surges during pump start-up and during pump shutdown. The pump control valves will be ball
valves or cone valves. The pump control valve will have a central nitrogen-charged hydraulic
accumulator to close the pump control valves during an electrical power failure. Each pump will
have an isolation valve°for maintenance of the pump and control valve. The discharge piping
from each pump will turn down under the floor and converge into a 54" header.
The high service pump station building will have a steel frame with precast concrete
panels. A bridge crane will be included to aid in the installation and servicing of the pumps,
motors, and valves. The building will have a truck access door for equipment removal. The
building will have a small control room that will be climate controlled and house the VFD and
7-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
High Service Pump Station and Storage
SCADA equipment. Toilet facilities will not be included in the building layout. The pump room
will be ventilated to reduce heat build-up from the pump motors.
7.4 ELECTRICAL AND INSTRUMENTATION
Preliminary studies indicate the larger pumps will be medium voltage and the smaller
pumps will be low voltage. The electrical power design will be determined at a later date.
Coordination with the power company will determine the type of starters required. Power factor
correction capacitors will be used if required by the power company.
Instrumentation will include the following:
· Pump Status
· Pump Control Valve Status
· VFD speed and set-point
· Pumping Pressure
· Flow Rate
· Accumulator pressure
· Motor bearings and RTD temperature
· Pump room and control room temperature
· Tank Levels
General alarm status will be provided for the following:
· High / Low Tank Level
· Motor protection features
· Pump failure
· VFD and Starter alarms
· Pump Control Valve failure
· Switchgear alarm
· Hydraulic accumulator low and high pressure
· Loss of communication
· Intruder Alarm
7.5
DISCHARGE PIPELINE
The City of Denton is designing the seven mile pipeline from the high service pump
station to the distribution system. Although the original design of the Hartlee Field Road Pump
Station included 4200 feet of discharge line, we recommend this line segment be included with
the seven mile pipeline to reduce construction cost. We recommend the pipeline be 54-inch
diameter to allow for acceptable head losses at the maximum pumping rate of 62 MGD. FNI
will coordinate with the City of Denton to verify system head conditions.
7-3
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
High Service Pump Station and Storage
A single flow meter and vault will be constructed on the discharge side of the pump
station. However, individual flow meters on each pump will be evaluated during the final
design. FNI recommends ultrasonic flow meter(s) be used because of low cost and the wide
operating range. A future pig launching station on the discharge pipeline will be provided for in
the design layout. Figure 7.3 shows the proposed layout of the treatment plant, tank field, and
pump station.
For further detail in this discussion, refer to Memorandum, "Cost Comparison of Hartlee
Field Road vs. Lake Ray Roberts Water Treatment Plant."
7-4
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Sludge Management
CHAPTER 8.0 SLUDGE MANAGEMENT
8.1 PURPOSE
There are two primary sludge generation soumes at the LRRWTP: 1) sludge from the
sedimentation basins, and 2) backwash waste sludge from the washwater recovery basin. The
backwash waste sludge volume from the washwater recovery basin is small compared to the
sludge from the sedimentation basins. Therefore, this section primarily focuses on sludge from
the sedimentation basins.
As initially designed, the LRRWTP would draw sludge from the sedimentation basins
and discharge it to four sludge lagoons. Also, the sludge that accumulated in the washwater
recovery basin periodically would be routed to the lagoons, via the basin drain system and
pumps. Sludge production calculations for the base case Conventional Coagulation, using an
empirical equation published by the AWWA Research Foundation suggest that the average
sludge production would be 3028 pounds per day.
The proposed regulations Stage 1 D/DBP on removal of the organic precursors
contributing to chlorine disinfection by-products would require DWU to change to an alternative
chemical treatment system (Ozonation) or dose the coagulant at a rate to achieve Enhanced
Coagulation. Under the first scenario (ozonation) the sludge production would be 2,788 pounds
per day, less than the conventional coagulation average production rate, due to the lower
chemical dosage. Under the second scenario (Enhanced Coagulation), the sludge production
would be 4,275 pounds per day, more than the conventional coagulation average production rate,
due to the greater chemical dosage. If the second scenario with the higher rate of sludge
production is selected, a re-evaluation of alternatives sludge disposal methods would be needed.
8.2 ALTERNATIVE EVALUATION
The daily sludge production data is necessary to evaluate the different sludge disposal
alternatives. Since the LRRWTP is a new plant and no sludge production data is available, the
daily sludge production rate was estimated based on the anticipated average chemical usage and
turbidity data. The average sludge production assuming Conventional Coagulation at a design
flow of 20 MGD is approximately 3,028 pounds per day on a dry weight basis. The volume of
8-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Sludge Management
wet sludge is calculated to be approximately 9,076 gallons per day by assuming 4.0 % solids in
the wet sludge. At a design flow of 50 MGD, the average sludge production is approximately
7,570 pounds per day on a dry weight basis and 22,690 gal/day assuming 4.0% solids in the wet
sludge.
The following sludge disposal alternatives, including the currently designed lagoon
system were considered:
Alternative No. 1: Construction of Lagoons: Under this alternative, the City would
remain with the initial design, and construct a four-compartment lagoon as designed.
Alternative No. 2: Installation of Sewer Line: This alternative would require construction
of a sewer line from the LRRWTP to the nearest sewer interceptor from the plant site. The sewer
line has to be designed to meet the plant's ultimate capacity of 100 MGD.
Alternative No. 3: Installation of a Belt Filter Press Facility: In this altemative, the City
would install a 1-meter belt filter press to mechanically dewater the sludge. One cell of the
existing lagoon would be used to store the sludge before the sludge is pumped to the belt press.
Alternative No. 4: Installation of Centrifuge Facility: In this alternative, the City would
install a centrifuge to mechanically dewater the sludge. One cell of the existing lagoon would be
used to store the sludge before the sludge is pumped to the centrifuge.
To evaluate and compare the various sludge disposal alternatives, the capital and
operating costs associated with each alternative were estimated. The capital cost was amortized
over 20 years at an interest rate of 7%. Both chemical (polymer) and power costs were assumed
to be constant over the next 20 years. The polymer usage data for the belt press facility was
obtained from the sludge settleability tests conducted by vendors on sludge collected from the
Lake Lewisville plant. The polymer usage data for the centrifuge option was provided by the
vendors. The sludge production was estimated to increase linearly, starting with the volumes
produced at 20 MGD and ending up at year 20 with the sludge production corresponding to the
50 MGD plant.
8.3 RECOMMENDATION
The evaluation was done assuming a base case sludge production scenario. Since
ozonation facilities are to be constructed at the facility, the sludge volumes are expected to
decrease significantly. This does not lower the construction cost of the lagoons since they are
8-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Sludge Management
designed for a 50 mgd capacity plant. However, it does lower the frequency of maintenance and
the surface loading on the lagoons, increasing their efficiency and economy.
Sludge lagoons have the advantage of requiring very little operation and maintenance.
The absence of sophisticated technologies makes it easier to operate, especially when compared
with the mechanical options.
The recommendation is to remain with the initial design. Under this alternative, a four-
compartment lagoon will be constructed. The lagoons will receive sludge discharged from the
sedimentation and washwater reclamation basins. After a lagoon compartment is filled with
sludge, it will be taken out of service. Water in the sludge will evaporate and solids will slowly
settle. Periodically, the water level will be lowered in the lagoon by removing stop logs or
opening shear gates. The decant water will drain by gravity to the washwater reclamation basin,
from where it will be returned to the head of the plant. Over time the sludge will dry and
become more concentrated. Upon reaching a solids concentration of approximately 30%, the
lagoon will be cleaned out with skip loaders. The solids would then be disposed of at the City's
landfill or land applied if a site becomes available.
For more details on this discussion, refer to Technical Memorandum No. 5, "Sludge
Dewatering Alternative Evaluation" in the Appendix.
8-3
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Administration Building
CHAPTER 9.0 ADMINISTRATION BUILDING
9.1 PURPOSE
Project Background
The original architectural design and related construction documents for the
administration building for the LRRWTP was prepared by Gary Juren in 1991; however, the
water treatment plant was not constructed at that time. Since 1991, several editions of the
Uniform Building Code (UFC) have been issued, some of which have changed life safety issues
used in the design of this building. There have also been significant changes in ADA
requirements over that same period. In addition, there are areas where the owner's criteria used
to plan the buildings has changed. The existing drawings have been evaluated by Freese and
Nichols with regard to these changed conditions and the original design has been modified to
reflect the revisions necessary to comply with the latest requirements.
Original Building Description
The original design consists of a linear floor plan having an administration area, a
maintenance shop along with associated parts storage and ancillary spaces, a chemical process
space, and an ammonia/chlorine storage and processing area, ail enclosed within a single
building shell. The administration area was designed as a two-story building, while the
remainder of the building is a one-story structure. The first floor consisted of an entrance lobby,
an office, conference room, a break room and restrooms, while the second floor had a control
reom, a laboratory and additional restrooms. A hydraulic elevator connected the two-story
portion of the building. The design included one interior staircase and a second set of stairs at an
exterior balcony which runs the length of the administrative area along the rear of the building.
The basic construction is a structural steel frame with steel joist and a metai deck, covered by an
insulation board and a metal standing seam roof system. The wall construction consisted of face
brick veneer.
The original mechanical system consisted of multiple small fan coil units and remote
condensing units located outside the building. This resulted in numerous small air conditioning
units rather than one central air handling unit.
9-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Administration Building
Advantages of this system include:
· Systems can easily be maintained by local mechanics. (These units are very similar to
residential units and can be serviced by any number of local companies.)
· Loss of one unit does not affect the air conditioning for the remainder of the building.
· Multiple units provide more individual control of room temperature.
Disadvantages of the original mechanical system include:
As each of the smaller units are designed slightly over the required loading conditions,
the more smaller units used, the greater the over-design of capacity provided.
The units are not as efficient as the larger systems, resulting in greater energy cost and
higher energy consumption.
9.2 BUILDING REVISIONS
Revised Design Criteria
Since the time the original building was planned and construction documents completed,
the building criteria have been re-evaluated by the owner. These modifications to the design
criteria required a re-evaluation of the entire program and modifications to the existing plans.
Basic considerations used in re-evaluating the floor plan are as follows:
Maintain the exterior profile of the building, along with maintaining the exterior
appearance as close to the original as possible.
Remove the hazardous materials (Ammonia and Chlorine) from the building and
construct a separate building dedicated exclusively for this purpose at a remote
location.
· Use the additional space gained by removing the ammonia/chlorine functions to
expand the various areas. This provides more flexibility and allows for future
growth.
Provide additional offices within the administration area.
Expand the break room and laboratory to allow for future growth.
· Re-design the spaces to avoid having a "wet" area above the electrical room.
· Utilize some of the lobby area for more functional usage.
Design Concepts
A particular concern was the location of hazardous materials within the same building
occupied by employees, as covered by the Uniform Fire Code (UFC). Regulations concerning
buildings housing hazardous materials have become more stringent in the last several years,
particularly in regard to toxic and highly toxic products, such as ammonia and chlorine.
Buildings housing ammonia and chlorine are considered as "hazardous occupancies", which
9-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Administration Building
requires that the design of these spaces comply with more stringent regulations than are required
for other type of occupancies. Removing these toxic producing gases from the building
simplifies the building design, including types of separation and fire protection standards that
would otherwise be required.
In addition to revisions in fire safety and building codes, there have been changes in
ADA requirements for buildings since this building was designed, which required re-evaluation
of the building in general, and restrooms in particular. The re-design of the building has taken
into consideration the newer ADA requirements. At the same time, the restrooms locations were
studied, and after careful consideration those restrooms located on the first floor were re-
positioned to be between the administrative functions and the shop area, so as to be available to
both. A hallway was added to connect both areas to the restrooms and break area, and which
provided an opportunity to install doors as sound barriers between these functions.
Planning Procedures
The FNI architectural team met with the owner's representatives in a series of workshops
to review the original building plans and discuss new design criteria. From these meetings, a
series of preliminary floor plans were prepared and discussed with the owner's representatives.
After several preliminary designs were prepared and discussed, a final scheme was prepared,
which is included as Figure 9-1. This schematic floor plan will be used to prepare the
construction documents for bidding and construction purposes. Additional meetings with the
owner's representatives during the final design phase will determine finishes and details
nec¢"~ary to complete the design.
Cost Differences
Construction costs have increased in the past ten years and these increased costs are
reflected in the latest estimate of probable construction cost. Addition of a new
Ammonia/Chlorine Building will also result in additional cost. Otherwise, relative costs for
internal changes in the d.esign should be approximately the same for the anticipated
modifications within the perimeter wall lines, except that where additional area has been added,
there will be a corresponding increase in cost. Additional cost will be also be incurred where the
9-3
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Administration Building
existing floor plan has been modified to re-claim some of the un-used, open lobby area at both
floors. These costs are indicated in the latest estimate of construction cost.
9.3 RECOMMENDATION
As stated above, the final preliminary floor plan was developed as a result of reviewing a
number of schemes with the owner, until a consensus was achieved. The final preliminary floor
plan is based on the design concepts listed above. Principally, the major considerations are the
removal of the ammonia/chlorine functions from this building and constructing a separate
hazardous materials building at a remote location, and re-using the existing design as nearly as
possible. The floor space originally used for ammonia and chlorine has been re-distributed
between the remaining functions, permitting expansion of each of these areas to fit the confines
of the perimeter shell. This provides for additional room for expansion as the plant operations
grow. Since the total building area is essentially the same as the original plant design, the cost
differences have been determined by:
· Adjusting the overall construction cost to account for inflation
· Increasing the cost as necessary to expand the building area
· Adjusting the cost to account for the re-distribution of spaces within the building
footprint.
· Adjusting the cost to create more functional spaces within the building footprint.
· Increasing the cost associated with the new detached hazardous material building
(Chlorine and Ammonia)
The schematic floor plan represented in Figure 9-1 indicates a slightly larger chemical
area, providing additional space for future expansion, while providing adequate space for the
immediate usage. An overhead service door has been added in the end on the structure,
permitting an easy method for serving the chemical spaces.
The shop area has been expanded to provide additional space for the future. A second
overhead service door has been added for the same reason. Since the shop area is located
between other spaces, thereby restricting future expansion, it is essential that adequate space be
provided to allow for growth, rather than finding that the service function has outgrown the
available area in the future. The electrical switchgear room has been re-located to the shop area,
solving the criteria to not have this area located under a wet area.
9-4
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Administration Building
The administrative area has been expanded into the shop area by approximately 512 sq fi.
As finish-out costs for this type of space is more expensive than that required for shop areas, it is
reasonable to assume that the expansion of the administrative areas will result in an increase of
approximately $22,500. In addition, open space in the lobby has been modified to make it more
usable by converting some of the area into offices and workrooms. The additional enclosed gpace
amounts to approximately 235 sq fi that was originally open lobby space. Using this space
requires additional floor framing, construction of partitions, and additional finishes. This could
result in additional costs in the $20,000 range. The administrative space has been increased by
closing in a comer that originally was under roof cover, but not enclosed by walls. In the final
design this space has been enclosed and will be finished as additional office space, with
approximately 1000 sq fi of additional structure. This will add approximately $100,000.00 to the
building cost.
Features of the final floor plan are as follows:
A. Four offices instead of the single office at the first floor. Two additional office
spaces are available at the second floor, which can be used for storage and later
converted into offices, as the need arises.
B. A larger break room with an expanded kitchen area. This provides additional
space for future increase in the number of employees.
C. A larger conference room with a storage room for tables and chairs when not in
use.
D. A plan room for storage of catalogs, records and plans plus a space for drafting
tables for spreading out the plans for examination.
E. A telecommunications closet for data terminals and telephone terminal cabinets.
F. A receptionist counter and workroom with space for a copier, fax, etc.
G. A separate file room for records.
H. A larger laboratory with two separate areas for different types of procedures.
I. A small office for the laboratory technician (records)..
J. A separate space off the operator's area for testing of water quality samples.
K. Additional storage space.
L. A room connected to the outside to serve as a "mud" room and storage of rain
gear.
M. A larger shop area with two service doors and additional space for future growth.
N. A large chemical processing area to provide for future growth.
O. An overhead service door located at the end wall of the chemical area to provide
an easy method for providing chemicals.
P. Installation of two polymer tanks within the building with feed slurry piping from
exterior source for service.
9-5
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Administration Building
Qo
The lobby area has been reduced in size by using part of this space for a
receptionist, workroom and files as noted above. The "open" space to the second
floor has been maintained to preserve open concept, only reduced in scale.
The final floor plans will be developed in compliance with the 1997 edition of the
Uniform Building Code, adopted by the City of Denton, the requirements of the Americans with
Disabilities Act of 1991, the Texas Accessibility Standards, and the appropriate chapters of the
Uniform Fire Code. In addition the ammonia/chlorine building will take into consideration the
additional provisions of the National Fire Protection
HAZARDOUS MATERIALS.
For more details on this discussion, refer
Administration (NFPA) Article 80,
to Technical Memorandum #6,
"Administration/Operations Building Floor Plan and Code Revisions"...in the Appendix.
9-6
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Hydraulic Analysis
CHAPTER 10.0 HYDRAULIC ANALYSIS
10.1 PURPOSE
Hydraulics is one of the primary considerations connecting the process design and the
physical topography of the site because the gradeline through the plant sets the elevation of the
processes. These elevations then are evaluated in relation to ground and water elevations at the
site to achieve an optimum design. At the same time, the lake elevations have to be considered
~ince gravity flow into the plant is desired.
During the original and current design, the primary hydraulic constraint on the project
involved the expected lake elevations and the conditions at the site for gravity flow through the
plant. A raw water pump station was required to allow gravity flow through the plant during low
lake levels. The introduction of the ozone contactors and the ground storage tank changed the
conditions at the site requiring a revised hydraulic analysis.
10.2 HYDRAULIC PROFILE
The revised preliminary hydraulic gradeline, which takes into account the ozone facility
and ground storage tank is presented in Figure 10.1. It shows a head loss of 22.7 feet. This is
2.7 feet more than the initial design. The proposed hydraulic gradeline has a plant influent
elevation of 612.7 feet and ends at an elevation of 590.0 feet at the transfer pump station.
The calculated gradeline provides for a reasonable elevation of the unit processes and the
operation building. It was a major concern in the initial design to assure that all units were
placed above high groundwater levels. The addition of the slurry trench wall allows the filters,
transfer pump station and washwater reclamation basins to be physically located below the water
line. A more detailed hydraulic profile will be developed during the final design.
10-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Backup Power Supply Evaluation
CHAPTER 11.0 BACKUP POWER SUPPLY EVALUATION
11.1 PURPOSE
From the TNRCC Chapter 290, Subchapter D Rules and Regulations for Public Water
Systems, Paragraph 290.45(b) "all surface water supplies must provide .... an elevated storage
capacity of 100 gallons per connection," or "sufficient emergency power must be provided to
deliver a minimum of 0.35 gallons per minute per connection in the event of the loss of normal
power."
With the increase in flow capacity from the initial LRRWTP design, the proposed
expansion capabilities and the relocation of the HSPS to this site, the treatment plant will become
a significant source of treated water for the DWU. Due to this increase in significance,
alternatives for a secure power source were examined to maintain uninterrupted operation.
11.2 EVALUATION ANALYSIS
Load Evaluation
Electrical loads derived for peak usage of equipment represent a statistical possibility by
assuming all ancillary operations are occurring at the same time, i.e.; raw water pumps, air
scouring, etc. while the heater system is at full force. The transfer pumps and raw water pumps
were calculated at the plant capacities of 20 MGD and 50 MGD. The high service pumps could
pump more than plant capacity because of peak requirements and the availability of ground
storage. The high service pumps rates of 24 MGD for the 20 MGD plant and 62.5 MGD for the
50 MGD plant were used for generator sizing.
Cost Comparisons
An alternative considering a power company second feed was determined to not be
feasible. This comparison was only between using a diesel engine or a natural gas generator as
backup power.
The diesel fuel consumption rate is approximately 78 gallons per megawatt hour or
7.8C/kWh at a cost of $1.00 per gallon. The gas consumption rate is approximately 9.8 MMBTU
I1-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Backup Power Supply Evaluation
per megawatt hour. For natural gas this is 2.8C/kWh at a cost of $3.0 per MMBTU. For propane
this is 4.6C/kWh at a cost of $4.40 per MMBTU.
With these fuel cost, and with a full load of 3 megawatts the generators would have to be
used for over 6,000 hour before the diesel system would become more costly than natural gas:
Difference in Capital cost: $920,000 = $1,810,000 - $890,000
Difference infuelcost: $900,000 = 6000 hrs x (2.8¢-7.8¢)/kWh x 3
megawatts
11.3 RECOMMENDATION
The relocation of the HSPS from the Hartlee Field Road site to the LRRWTP site
requires a high level of reliability of power supply to the site. The distance from the nearest
independent electric power substation (City of Denton, or other electric power supplier) to the
site makes back-up power via dual feed economically unattractive. Additionally, the control of
reliability of electric power to the site would diminish if the City of Denton Electric Utility were
to be sold as a result of the imminent electric power industry deregulation. Accordingly, back up
power in the form of diesel powered generators has been added to the LRRWTP.
A single utility company service at the LRRWTP with a diesel power generator system
located at the LRRWTP is recommended to provide normal and backup power at both the WTP
and the Raw Water Pump Station.
Diesel is recommended over natural gas because of the initial capital cost and annual
maintenance cost. Natural gas fuel cost saving will never be realized with. the generators used as
backup power only. The actual runtime for the generator in a backup mode would average less
than 100 hours per year; i.e. $7,800 for diesel fuel. Natural gas does burn cleaner than diesel by
producing less than one third the ozone emissions. However, there is no financial incentive for
using natural gas over diesel at this time because generators used for backup power are not
regulated for emissions. The proposed emissions controls for diesel engines (TNRCC, Chapter
14 - Control of Air Pollution from Motor Vehicles, Rule Log Number 99055A- 114-AI & Rule
Log Number 99-055-SIP-AD in the four county DFW nonattainment area address two rules
changes; fuel and flue-gas cleanup. The proposed rule change for fuel is interpreted currently as
applying to only motor vehicles. However, it will likely become a standard applying to all low
11-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Backup Power Supply Evaluation
volume users such as emergency diesel generators. The LED (Low Emission Diesel) fuel will
likely cost only 4¢ per gallon more, an increase of $312.00 per year for 100 hours of operation.
A proposed emissions control on non-road diesel engines for the flue-gas cleanup is likely to be
implemented before 2007. Though backup generators may be exempt from this regulation, an
EPA study on stationary engines has shown that retrofit SCR technologies can meet their
emission standards levels. Manufacturers have yet to establish costs for this retrofit equipment.
A single 3 phase overhead high voltage line between the facilities is recommended to
provide both utility and backup generator power. A single generator system reduces maintenance
and allows generator power not needed for raw water pumping to be used at the LRRWTP. With
this design a single service from the utility company would also provide the best overall electric
rate for power.
With the high service pumping located at the LRRWTP the initial system should be
3.0MW comprised of two 1.5MW generators. If a single generator failure occurs the TNRCC
requirements for the minimum distribution delivery could still be met with only one generator.
The generator system could be expanded with the same size generators with the WTP
expansions, adding the generator cost as needed. Using the same size generators, the
maintenance costs will be minimized.
Though not within the scope of this backup power system study, it is recommended that
transformer redundancy be considered for the WTP and the raw water pumping station design.
Transformer redundancy will minimize the possibility of a single point of failure at a minimal
cost. A site layout of the back-up power supply generator building can be found in Figure 11.1
For more details on this discussion refer to Technical Memorandum No. 7, "Back-up
Power Requirements" in the Appendix.
11-3
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Electrical/Instrumentation and Control
CHAPTER 12.0 ELECTRICAL/INSTRUMENTATION AND CONTROL
12.1 PURPOSE
The original design for the LRRWTP was completed in 1991, but the plant was not
constructed. The original design utilized a Distributed Control System (DCS) for plant
automatic control and monitoring. Since 1991 there have been significant changes in control
system technology and instrumentation systems that can be applied to the control and monitoring
of water treatment plants.
To be more cost effective, the City of Denton desires to automate the LRRWTP to
mazimize the productivity of staff time. This requires that the control system be capable of
operating the plant in a full automatic mode. Additionally, the control system must be capable of
alerting operating personnel of alarm conditions (off-site and/or away from the control room) as
well as performing a plant shutdown in abnormal conditions.
12.2 ALTERNATIVE EVALUATION
Two alternative control system design approaches were evaluated. The first approach is
similar to the original DCS design except Programmable Logic Controllers (PLC) are utilized in
place of the DCS control units, and a commercial software package (i.e., Intellution,
Wonderware) is utilized for operator interface. The second approach eliminates most of the
PLCs and provides a direct communication link between the operator interface software and the
field instrumentation, valve actuators, and motor control devices. In this design approach, the
operator interface software would perform the control and logic functions.
These two alternatives were evaluated based on the following criteria:
· Functional performance
· Reliability
· Maintainability
· Cost
Functional performance is defined as the ability to perform the required process control,
process monitoring, and equipment monitoring functions that will be required at the LRRWTP.
In terms of process control and process monitoring, each alternative is considered equal. Both
alternatives are well able to perform the required process control, interlock and sequencing
12-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Electrical/Instrumentation and Control
functions. For equipment monitoring, the second approach that communicates directly to
instruments, valve actuators, and motor control devices provides better equipment monitoring
capabilities. This is because additional data is gathered from the control devices such as motor
current, torque, etc. By trending this data over time the equipment performance can be closely
monitored and predictive maintenance can be implemented.
Although both alternatives were considered highly reliable, overall, the second alternative
(direct communication link) is slightly, more reliable. Both alternatives require the primary
instruments and final control elements to be fully functional for the system to be fully
operational. Also, both alternatives require the operator interface software to provide all aspects
of the control and monitoring system. Because the first alternative has an additional PLC cOntrol
layer there is an increase in the probability of failure. Another aspect of failure is how the
process responds to a failure of the primary control unit. In the second alternative, the individual
final control elements operate autonomously and therefore they would remain at their last
position, speed, etc. in the event of a failure of the control computer or communications link.
Between the two alternative systems, the second alternative is easier to maintain. This is
primarily due to the fact that there are fewer components and wiring as the PLC and manual
backup panels (including associated wiring) are eliminated. Smart instruments that are
connected through a digital communications cable can be calibrated on-line. Items such as valve
actuators that communicate directly are easier to maintain as high maintenance items like limit
switches and feedback potentiometers are eliminated. Further, the use of smart instruments and
control elements can often provide helpful trouble shooting information in the case of a failure.
As the smart instrument concepts continue to mature, a conversion of communication systems
develops making replaceable devices more homogenous. This increases options for future
replacement devices.
In comparing the cost of these two control system design alternatives several aspects
were investigated. There are significant savings with the second alternative. There are savings
associated with the deletion of the PLCs and manual back-up panels, and those associated with
simpler check out and start-up requirements. The estimated total saving from the elimination of
PLCs and panels is approximately $190,000.
12-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Electrical/Instrumentation and Control
12.3 RECOMMENDATION
Based on the above evaluations, the recommended design approach provides a direct
communication link between the operator interface software and the field instrumentation, valve
actuators, and motor control devices, and the operator interface software performs the control
and logic functions. At several locations, a small PLC may be needed to provide a cost-effective
interface to some instrumentation. Also, at the raw water pump station a small PLC will be
provided due to the distance of the communications link. A separate PLC is also recommended
at the ozone generation building.
The direct communication link approach is an emerging trend in control system
applications and has been successfully employed by Montgomery Watson on several projects for
the City of Houston. The recommended manufacturers from the original design specifications
were contacted to ensure that this technology was available from the City of Denton's preferred
vendors. It was found that direct digital communication links were available from listed
manufacturers of motor controllers, variable speed drives, valve actuators, chlorinators,
ammoniators, and most instruments and analyzers, thereby ensuring a competitive and viable
bidding situation.
Description of Recommended Control System
A brief description of the recommended control system design is presented below.
At the raw water pump station a small PLC will be provided for raw water flow and
pump control. The PLC will communicate digitally to the raw water pump variable frequency
drives (VFD) and raw water control valve actuators. The raw water pressure, flow, turbidity, pH,
and temperature transmitters will be wired to PLC analog input cards. Spread spectrum radio is
recommended for communications between the raw water PLC and the central control computer.
For the chemical feed systems, rapid mixers, flocculation drives, sludge collection drives,
and telescoping valves a single twisted pair cable will be wired to each chlorinator, ammoniator,
chemical feed pump VFD, rapid mix pump starter, flocculator VFD, sludge collector motor
starter, and telescoping valve actuator and wired back to the operator interface. Interlocks such
as chlorine high/low vacuum switches would be wired directly to the individual microprocessor
controlled chlorinators.
12-3
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Electrical/Instrumentation and Control
For the filter control system, a single twisted pair cable will be wired to each filter control
valve actuator (influent, effluent, air wash, wash water drain and filter to waste valves). A
second twisted pair may be used to communicate to the filter effluent turbidity meters as the
protocol used by Hach (Lon Works) is probably different than that utilized by the valve actuators
and not ail software packages can communicate multiple protocols through the same port. Filter
level monitoring would be through a multi-sensor ultrasonic level system.
For the high service pumps, waste water pumps, supplemental backwash pump, and air
blowers, a single twisted pair cable will be wired to each motor starter or VFD.
The central computer system will be a redundant PC configuration connected through a
TCP/IP Ethernet LAN. Report and alarm printer would be shared through the network.
Communications to the raw water pump station and the possible off-site high service pump
station would be over spread spectrum radio. The system can also be expanded to include a
remote site SCADA system and bridged to a computer control system at the existing Lake
Lewisville water plant.
The control software will be Fix DMACS by Intellution or a similar commercially
available product. Final software selection will be made at a later date. The software will be
configured to provide complete plant graphic displays including:
· A plant overview display
· Unit process displays for each unit process
· Detailed displays for each unit within a unit process
· Control pop-up windows for each valve, drive and control loop
· Trend displays for all critical variables
As part of the alarming system, the software will be able to page or dial out alarm
conditions during unmanned operations. Offsite personnel will be able to dial-in to the system
using a laptop computer running the operator interface software. With appropriate security
codes, the operator will be able to perform all control and monitoring functions through the
laptop computer. The system will also be programmed to perform an orderly plant shutdown
when the plant is unmanned and conditions warrant.
The software will be configured to automatically produce the necessary plant operations,
maintenance and regulatory reports. This will include the required TNRCC reports, production
reports, and chemical and electrical usage (production cost) reports.
12-4
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Electrical/Instrumentation and Control
For more detail on this discussion, refer to Technical Memorandum No. 8, "Control
System Design Alternative Evaluation" in the Appendix.
12-5
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Recommendations
CHAPTER 13.0 RECOMMENDATIONS
13.1 RECOMMENDATIONS
The LRRWTP for the City of Denton was originally designed to have a 10 MGD
capacity, but was not constructed due to the City's re-evaluation of water demand projections.
The growth in Denton County over the last ten years and the associated increase in water demand
requires that the City constmct'a treatment plant with a capacity of 20 MGD by the year 2002.
The capacity increase of the plant, technological advances and regulatory modifications
led to a review of the units to be included at the plant. The following recommendations are
based on the original design, and include the modifications discussed in this report. The units to
be used are shown in Figure 13-1 and summarized in Table 13-1. The following are the
recommended processes:
· Raw Water Pumping Station. Remained in accordance with the original design.
· Influent Flow meter. Also included in the original design, but re-sized to account for a
larger range of flow.
· A Pm-ozone Contactor. Added to the initial design. The flow would flow through the
contactor, at a maximum applied ozone dose of 1 mg/L, to enhance microflocculation and
improve turbidity removal.
· Pumped Diffusion Mixing. In accordance with the original design.
· Splitter box. This unit needed to be added, since the original design only consisted of one
train. This unit uses a hydraulic split to divide the 20 MGD capacity into two 10 MGD
capacity treatment trains.
· Flocculation Basins. The design configuration remains the same. Another basin is added
to account for the flow increase.
· Sedimentation Basins. The design remains the same. Another basin is added to account
for the flow increase.
· Intermediate Ozone Contactor. Added to the initial design. The intermediate ozone
contactor serves as a primary disinfectant unit at a maximum applied dose of 3.5 mg/L.
· Filters. Although the basic layout, remains the same, several significant changes are made
to the original design. GAC is to be used as media, and air scour is used instead of
surface wash during the backwash. Filter to waste provisions are added.
· Waste Washwater Reclamation. The design remains in accordance with the original
design, although the waste production is expected to decrease due to the use of ozone.
· Sludge Drying Lagoons. The design remains identical to the initial layout, although the
sludge production is expected to decrease due to the use of ozone.
· Transfer Pump Station. Added to the original design. A pump station will lift the flow to
the ground storage tank.
· Clearwell. The design changed from an underground 1 million-gallon concrete tank, to a
ground level 6 million gallon pre-stressed concrete or steel tank.
13-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Recommendations
· High Service Pump Station. The HSPS was located, in the initial design, at the Hartlee
Field Road site, but has been relocated the LRRWTP site. The conceptual design
remains the same, but the capacity and discharge head have increased to reflect the
changed site conditions.
· Slurry Trench Wall. Added to the original design. A trench wall surrounding the filters,
the washwater reclamation basin and the main drain pump station, among other units,
keeps the groundwater away from these units.
· Administration/Operations Building. The overall footprint of the building remains the
same, but the internal space is modified to be more functional.
· Back-up Power Supply. Added to the original design. The location of the HSPS to the
LRRWTP site requires the reliability of power provided by back-up diesel powered
generators at the site.
· Bulk Chlorine/Ammonia Storage and Feed. Added to the original design. A separate
building for the storage and feeding of chlorine and ammonia has been added to improve
site safety with respect to hazardous materials.
13.2 BULK CHLORINE/AMMONIA STORAGE AND FEED
An uncovered, pad mounted bulk ammonia storage tank was designed in the original
LRRWTP design. Due to new UFC and RMP requirements, we recommend that the ammonia
tank be constructed in an enclosed building. We also recommend that an ammonia scrubber be
designed to scrub the enclosed space containing the storage tank.
The original LRRWTP design utilized ton containers to store and feed chlorine. These
cylinders were set in a semi-enclosed area. This storage system design needs to be revised to
meet the requirements of the UFC and RMP. We recommend that bulk storage tanks be used to
store chlorine at the LRRWTP in an enclosed building. For the 20 MGD plant, a 25-ton bulk
storage tank is recommended. A chlorine scrubber will also be designed to treat any potential
leaks in the bulk chlorine storage room. The bulk storage of chlorine will provide the following
additional advantages over the ton cylinders.
· Chlorine unit cost for bulk delivery is 15 to 20% less than the chlorine unit
cost for ton cylinders
· Bulk storage system is safer because of less frequent handling Of cylinders.
· The proposed bulk storage design will meet the requirements of the UFC and
RMP.
· The bulk ammonia tank concept has similar advantages to the chlorine bulk
tank.
13-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Recommendations
The proposed layout of the chlorine and ammonia storage and feeding facilities is shown
in Figure 13-2. The layout and design elements will be finalized in a workshop during final
design.
13-3
TABLE 13.1
PRELIMINARY DESIGN CRITERIA
LAKE RAY ROBERTS WATER TREATMENT PLANT
Item
Plant Capacity
Raw Water Pumping Station
Number of Pumps
Capacity (each)
Influent Flow Meter
Type
Number
Size
Capacity
Ozone Generators
Number
Capacity (each
Total Capacity
Lox Storage Tank
Capacity
Pre-Ozone Contact Basins
Type
Number
Length (each)
Width (each)
Water Depth
Volume (each)
Volume (total)
Design flow per
contactor
Detention time at design
flow
Units Initial Interim Ultimate
mgd 20 50 100
no. 2 3 5
mgd 20 25 25
Universal Venturi Tube
no. 1 1 2
in 30 42 42
mgd 8-50 15-70 30-140
no. 2 2/1 2/2
lb/day 1,000 1,000/2,000 1,000/2,000
lb/day 2,000 3,000 6,000
gallons 15,000 15,000 30,000
Under/Over Baffle
2 5 10
R. 39 39 39
R. I0 10 .10
R. 22 22 22
gal 64,200 64,200 64,200
gal 128,400 321,000 642,000
MGD 10 10 10
(min) 8 8 8
Comments
The interim capacity is
based on the dependable
yield of 19.76 mgd
available to the City of
Denton from Lake Kay
Koberts multiplied by 2.22
which is the maximum day
drought demand factor.
Ultimate capacity is for a
regional plant
Minimum number with at
least one standby pump at
each capacity. Initial
pumps are to be modified
to 25 mgd capacity for
Interim.
A backup ozone generator
is supplied for reliability
13-4
TABLE 13.1
PRELIMINARY DESIGN CRITERIA
LAKE RAY ROBERTS WATER TREATMENT PLANT
I[em
Flash Mix
Type
Number
G~value
Mixing time
Pump Capacity
Motor Horsepower
Splitter box
Type
Capacity
Flocculation Basins
Type
Number of Basins
Size (each basin)
Water Depth
Stages
Volume (each basin)
Volume (total)
Detention Time
Flocculators:
Type
Number (each basin)
Number (total)
Mixing Energy (G, sec
1 st Stage
2"a Stage
3ra Stage
Sedimentation basins
Type
Number
Size (each basin)
Water Depth
Volume (each basin)
Volume (total)
Detention Time
Units Initial Interim Ultimate
Pumped Diffusion
no. 1 1 2
sec'~ 750 750 750
sec 1.25 0.5 0.5
gpm 400 400 400
hp 5 5 5
Hydraulic Split
mgd 20 50 100
no. 2 5 10
ftxft 37x64 37x64 37x64
ft. 12 12 12
no. 4 4 4
ft3 27,650 27,650 27,650
ft3 55,300 138,250 276,500
min 30 30 30
no. 6 6 6
no. 24 60 120
see't 60 to 20 60 to 20 60 to 20
sec'~ 60 to 20 60 to 20 60 to 20
' see'~ 40 to 5 40 to 5 40 to 5
Rectangular, plug flow
No. 2 5 10
ftxff 44x285 44x285 44x285
ff 13.5 13.5 13.5
ff~ 169,290 169,290 169,290
338,580 846,450 1,692,900
Min 180 180 180
Comments
Horizontal flow, baffled
and compartmentalized for
plug flow characteristics
Stages separated by
diffuser walls
Vertical shaft (variable
speed in all stages)
Two in each stage
13- 5
TABLE 13.1
PRELIMINARY DESIGN CRITERIA
LAKE RAY ROBERTS WATER TREATMENT PLANT
Item
Surface Loading Rate
Weir Overflow Rate:
End Weir (Length)
Overflow Rate
Sludge Collectors:
Type
Units Initial Interim Ultimate
gpd/£( 797 797 797
ff 360 360 360
gpd/ff 27,700 27,700 27,700
Number (each basin) no. 2 2 2
Number (total) no. 4 10 20
Speed fpm 2 2 2
Intermediate Ozone Contact Basin
Type
Number No
Length (each) Ft
Width (each) Ft
Water Depth Ft
Number of Cells (per
contactor)
Volume (each) Gal
Total Volume Gal
Design Flow Per MGD
Contactor
Detention Time at
Design Flow (min)
Filters
Type
Number No. 8
Size ftxft 16x29
Area (each) ~ 464
Area (total) ft2 3712
Filtration Rate
With all filters gpm/ft2 3.75
With one filter out gprrdff2 4.30
Backwash Rate
Maximum gpm/ft2 18
Average gpm/ft2 15
Comments
State requirement is a
maximum of 800 gpd/ft2
3 total each basin (59ftx2ff
each)
State requirement is
20,000 gpd/ft maximum
Chain and Flight (with
small chain and flight
cross collector)
2 5 10
86 86 86
10 10 10
22 22 22
8 8 8
141,200 141,500 141,500
283,000 707,500 1,415,000
10 10 10
18 18 18
16 32
16x29 16x29
464 464
7424 14,848
4.70 4.70
5.00 5.00
18 18
15 15
Gravity, equal loading
self-backwashing
13- 6
TABLE 13.1
PRELIMINARY DESIGN CRITERIA
LAKE RAY ROBERTS WATER TREATMENT PLANT
Item Units Initial Interim Ultimate Comments
Filter Media
GAC Depth (in)
Sand Depth (in)
Surface Wash
Type
# of blowers
Pressure (psi)
Rate scfm
44 44 44
6 6 6
2 2 4
7.5 7.5 7.5
2,300 2,300 4,600
Waste Washwater Reclamation
Volume per backwash gallons 35,728
Maximum filter wash no. 3
cycles per day
Waste production rate mgd .43
(maximum)
Washwater Holding Tank:
Number no. 1
Size (each) ftxft 50x60
Effective water depth ft 6.5
Effective volume gallons 145,860
Sludge Drying Lagoons
Estimated Production (dry solids)
Average lb/day
35,728 35,728
3 3
Critical lb/day
1.68 3.2
1 2
50x60 50x60
6.5 6.5
145,860 291,720
2,788 6,970 13,940
12,217 30,544 61,089
Volume of Sludge
Produced at 4% solids
(641bs/ff3)
Average ft3/day 1,095
Critical 4,838
Lagoon Sizing
Number no. 4
· 2,737 5,475
12,095 24,191
4 8
Effective Depth ft 6 6
Area (each) ft2 12,000 12,000
Volume (each) ft3 72,000 72,000
Volume (total) f¢ 288,000 288,000
Days of Storage
Average days 263 105
6
12,000
72,000
576,000
105
Worst case, 3 backwashes
per filter per day
Sized for two backwash
volumes each
10 NTU and 7 mg/1 ferric
sulfate
50 NTU and 17 mg/1 ferric
sulfate
Critical period assumed at
one month per year
Designed to handle critical
month at ultimate capacity
13- 7
TABLE 13.1
PRELIMINARY DESIGN CRITERIA
LAKE RAY ROBERTS WATER TREATMENT PLANT
Item
Units Initial Interim Ultimate
Comments
Critical
Clearwell
Type
days 59 24 24
Number no. 1 3 6
Capacity (total) gal 6x106 6x106 6x106
Water Depth (minimum) ft 32 32 32
Diam ft 180 180 18
High Service Pump Station
Number of Pumps
no.
3/1 5/1 10/2
Capacity(each) mgd 14/6 14/6 14/6
Firm capacity Mgd 34 62 128
Circular steel or pre-
stressed concrete tank
Minimum number with
one standby pump at each
capacity
[dtn99479]word2000\TAFINAL REPORT~Table_ 13.1 .doe
-- 13- ~
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Recommendations
CHAPTER 14.0 PROBABLE CONSTRUCTION COSTS
The estimated opinion of probable construction cost for the new Lake Ray Roberts Water
Treatment Plant is shown in Table 14-1. The total estimated capital cost for the Raw Water
Conveyance facilities is approximately $2.3 million. The capital cost of the 20-mgd WTP
including the Administration/Operations Building and the back up power generators is estimated
at $ 26.2 million. The relocated clearwell storage and High Service Pumping facilities are
estimated at approximately $6.3 million. The total for the facilities is estimated at approximately
$35 million. The estimates include all costs associated with the construction contract including
contractor's overhead and profit as well as 10% for contingencies. Construction cost estimates
were based on equipment and unit costs at Year 2001 dollars.
It is important to recognize that all costs show on Tables 14-1 are preliminary estimates
based on actual costs for similar facilities and assume typical construction conditions. They
cannot account for all of the factors unique to the new Denton site and the construction project
bidding environment at the time of bid opening. Currently in North Texas there is a low level of
competition, and a higher than normal labor cost resulting in higher overall project costs.
Consequently, the cost estimates should be considered to be a "budget estimate." The estimated
range of costs of the 20 MGD plant, including the high service pump station, should be between
$34 and $36 million. These estimates will be revised during the final design.
14-1
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Recommendations
Table 14-1 - Opinion of Probable Construction Cost
Summary of Cost - 20 MGD Ozone Plant and 60 MGD Pump Station
RAW WATER PUMP STATION AND PIPELINE -2001
UNIT
ITEM DESCRIPTION QUANTITY UNIT PRICE TOTAL
Raw Water Pump Station/Pipeline/Electrical 1 LS $965,262 $965,262
Raw Water Electrical Building (^) 1 LS $56,300 $56,300
Raw Water Pipeline 1 LS $1,108,723 $1,108,723
Electrical Instrumentation (B) 1 LSA $183,881 $183,881
TOTAL COST - 2001 $2,314,166
20 MGD OZONE PLANT - 2001
UNIT
ITEM DESCRIPTION QUANTITY UNIT PRICE TOTAL
Raw Water Meter Vault 1 LS $111,537 $111,537
Pumped Diffusion Vault (c) 1 LS $119,746 $119,746
Splitter Box {c~ 1 LS $209,254 $209,254
Flocculation and sedimentation Basin 2 LS $1,479,557 $2,959,113
Ozone Facility (D) 1 LS $5,100,000 $5,100,000
Filters 2 LS $1,883,600 $3,767,200
Air Scour System 1 LS $477,289 $477,289
Transfer Pump Station (E) 1 LS $808,000 $808,000
Chemical Storage Tank Area 1 LS $702,838 $702,838
Chemical Feed Facilities 1 LS $1,260,131 $1,260,131
Chemical Pipe Chase 1 LS $617,120 $617,120
Lined Chemical Drain Pit 1 LS $53,944 $53,944
Chlorine and Ammonia Storage Building 1 LS $631,955 $631,955
Sludge Dewatering System (v~ 1 LS $800,000 $800,000
Washwater Reclamation Basin 1 LS $422,042 $422,042
Washwater Recycle Meter Vault 1 LS $48,081 $48,081
Main Drain Sump 1 LS $149,845 $149,845
Operations Building (~) 1 LS $1,662,000 $1,662,000
Slurry Trench ® 1 LS $338,000 $338,000
Yard Piping 1 LS $550,597 $550,597
Sitework/Paving 1 LS $612,410 $612,410
Landscaping and Irrigation 1 LS $65,150 $65,150
w (H)
Backup Po er 1 LS $890,000 $890,000
Electrical Instrumentation 1 LS $3,863,925 $3,863,925
TOTAL COST - 2001
$26,220,177
14-2
MODIFICATIONS TO LRRWTP PRELIMINARY DESIGN
Recommendations
HIGH SERVICE PUMP STATION - 2001
ITEM DESCRIPTION QUANTITY UNIT UNIT TOTAL
PRICE
60 MGD Pump Station 1 LS $3,805,310 $3,805,310
6 MG Storage 1 LS $1,415,930 $1,415,930
Plant Effluent Meter Vault 1 LS $114,143 $114,143
Electrical/Instrumentation ~B) 1 LS $960,369 $960,369
TOTAL COST - 2001
$6,295,752
*Unless indicated otherwise, unit prices are taken from the initial cost estimate multiplied by the ENR index factor
of 1.303 to change costs to 2001 dollars.
A) Unit price is reduced since potassium permanganate feeding facility is taken out from initial design.
B) E/I&C is based on 18% of plant costs. Increased to account for new equipment. Includes RWPS but not
pipeline. Does not include extra for Backup Power.
C) Unit Price from TM-3, Alternative B. Pumped diffusion mixing with splitter box, 23-Nov-99.
D) Unit Price from TM-2, Table E-4, 23-Nov-99.
E) Unit Price from Memorandum "Cost Comparison of HFR vs LRRWTP, 8-Jan-00.
F) Unit price for Lagoon Facility from TM-5, 10-Dec-99.
G) Unit Price is increased by comments in revised TM-6, and contingencies are increased from 10% to 15%.
H) Unit Price from TM-7, 19-Jan-00.
14-3
The following figures are located in the Exhibits File:
ES-l, ES-2, 3-1, 3-2, 3-3, 4-1, 6-1, 6-2, 6-3, 7-3, 7-2, 7-3, 9-1, 10-1, 11-1,
13-1, 13-2
AGENDA INFORMATION SHEET
Agenda No.~
Agenda Ite. n)
AGENDA DATE: April 11, 2000
DEPARTMENT: Electric Utility
ACM: Howard Martin, 349-8232
SUBJECT:
Receive a report and give direction regarding:
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DENTON, TEXAS
DETERMINING COMPETITIVE MATTERS RESPECTING CERTAIN PUBLIC POWER
UTILITIES WHICH ARE SUBJECT TO PROTECTION UNDER THE TEXAS OPEN
MEETINGS ACT AND THE TEXAS PUBLIC INFORMATION ACT; ADOPTING
DECLARATIONS AND FINDINGS IN THE PREAMBLE; AND PROVIDING FOR AN
EFFECTIVE DATE.
BACKGROUND:
Senate Bill 7, that was enacted into law by the 76th Texas Legislature, created a public power
exception to both the Texas Open Meetings Act and the Texas Public Information Act for
municipal electric utilities. This exception is designed to provide a "level playing field" for all
participants in the existing competitive Texas electric wholesale and newly defined competitive
electric retail market. Private entities participating in the electric market have always been able
to protect virtually all of their activities such as strategies, planning discussions, detailed
financial information, purchasing activities, and technical data from public dissemination. Prior
to the passage of Senate Bill 7, municipal electric utilities were required to make virtually all
their decisions and data available to the public, including other electric providers. Except in
unusual situations, such as DME's dual and triple certified areas, this was not a problem as long
as electric utilities were limited to serving customers in exclusive service territories.
With the advent of competition in the wholesale marketplace after the 1995 Legislation session,
this began to become a problem. For example, knowledge of scheduled outages ora utility's
generating units provided power marketers with the ability to raise prices for replacement power
because they knew how badly that power was needed by the utility with the outage. Private
utilities and power marketers have been successful in preventing the public dissemination of the
prices at which they bought and sold wholesale power both before and after the transactions took
place. However, municipal utilities could not prevent their competitors in the wholesale market
from determining that same information, either by attending open meetings where transactions
were approved or through open records requests.
Without the changes made to the Texas Open Meetings Act and the Texas Public Information
Act made by the 76th Texas Legislature, when full retail competition takes place the situation
would have become even more difficult for municipal utilities. For municipal utilities that are
competing in any form, either through "opting in" to retail competition or in multiply certified
areas, competitors would be able to determine every action planned by the municipal utility in
the competition for energy customers and new distribution customers (in multiply certified areas)
while maintaining the confidentiality of their information. For municipals who "opt out" of
competition, operational and cost information could be used in development of take-over efforts,
efforts to persuade businesses to locate outside of a municipal utility service area, and in
preparation to attack the municipal utility as soon as it "opts in" to retail competition. An "opt-
out" utility that conducts it business totally in the open until the day it "opts-in" can be assured
that competitors will use that information to prepare an assault on its customers as soon as it is
possible to do so.
The intended effect of the changes made to the Texas Open Meetings Act and the Texas Public
Information Act made by the 76th Texas Legislature was to allow public utilities to make only
the same amount of information available in public that private utilities provide in public. It is
unfortunate that, in order to protect the significant investment our citizens have in their electric
utility and the revenue provided to the City from those investments in the new deregulated
environment, a portion of the total openness of the electric utility management has been lost.
However, we are fortunate that we retain the oversight of the electric utility operations by elected
officials who are available to accept citizen input at all times. Denton Municipal Utility intends
to remain responsive to its citizen customer/owners.
The purpose of this resolution is:
· To provide the citizens of Denton a clear understanding of how the City intends to implement
this new law, and;
· To provide Council guidance to the Public Utilities Board, the City Attorney, and the electric
utility staff on application of this exception.
This resolution is similar to the attached resolutions that have been adopted by San Antonio, the
Lower Colorado River Authority, and the City ofBoeme. TPPA also indicates that resolutions
using "basically the same approach" have also been adopted by New Braunfels, Kerrville,
Lubbock, Bryan, and Brownsville.
The competitive issues listed in the Resolution are divided into six areas. The Financial
Information section contains items that would:
· Establish DME risk management strategies for fuel and purchase power supply costs.
· Allow competitors to influence fuel markets to the detriment of DME
· Determine the financial strength of DME
· Allow competitors to forecast DME rates
· Allow competitors to develop low cost take over proposals
· Allow competitors to assess competitive strengths or weaknesses of DME and its ability to
withstand preditory price reductions by others.
The Purchasing and Contract Information section contains items that would:
Allow competitors to influence the wholesale power market to the detriment of DME
· Establish levels that DME would be willing to pay for wholesale power
Establish levels that DME would be willing to pay for fuel or the transportation of fuel.
· Allow competitors and vendors insight into DME purchasing habits and identity of suppliers
on which DME relies heavily
The Business Operations Information section contains items that would:
· Inform competitors of DME's strategic and business plans
· Inform competitors of the strengths and weaknesses of DME's operation.
· Assist competitors in formulating offers to hire key DME employees.
· Inform competitors of DME strategy regarding either the sale or acquisition of assets.
The Generation/Transmission/Distribution System Operations Information section contains items
that would:
· Allow wholesale power marketers to take advantage of generating unit outages to raise prices
for replacement supplies of energy and capacity
· Determine DME's production costs for its power supply
· Determine DME's growth rate and need for additional capacity
· Allow competitors to develop valuations of DME's assets in preparation of take over
attempts.
· Determine DME's need for critical pieces of equipment whose availability could be
influenced by the purchasing schedules of competitors.
The Sales, Market Research and Marketing section contains items that would:
· Allow competitors to adjust their sales and marketing strategies to undercut DME's efforts to
add customers to its system and retain existing customers.
The Competitive Customer Information section contains items that would:
· Allow competitors to target DME's most valuable retail customers
· Protect the privacy of its customers' energy consumption records.
OPTIONS:
1. Adopt Resolution as presented
2. Determine all "competitive matters" on a case by case basis in closed PUB and Council
sessions.
RECOMMENDATIONS:
Adopt this resolution as presented.
PRIOR ACTION/REVIEW (Council, Boards, Commission):
There has been no official action or review of the Resolution by the Public Utilities Board.
However each member has been given an opportunity to review the proposed Resolution and
provide comments and suggestions.
FISCAL INFORMATION:
None
Respectfully submitted:
Sharon Mays
Director of Electric Utilities
RESOLUTION NO.
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DENTON, TEXAS
DETERMINING COMPETITIVE MATTERS RESPECTING CERTAIN PUBLIC POWER
UTILITIES WHICH ARE SUBJECT TO PROTECTION UNDER THE TEXAS OPEN
MEETINGS ACT AND THE TEXAS PUBLIC INFORMATION ACT; ADOPT1NG
DECLARATIONS AND FINDINGS IN THE PREAMBLE; AND PROVIDING FOR AN
EFFECTIVE DATE.
WHEREAS, Senate Bill 7 ("SB 7") was enacted into law by the 76th Texas Legislature, and
signed by the Governor on June 18, 1999, with an effective date of September 1, 1999. Said SB
7, among other things, amended Subchapter D, Chapter 551 of the Texas Government Code (the
"Open Meetings Act") by adding a new Section 551.086 thereto, commonly referred to as the
"Public Power Exception"; and
WHEREAS, SB 7, amended Subchapter C, Chapter 552 of the Texas Government Code (the
"Public Information Act") by adding a new Section 552.131 thereto, commonly referred to as the
"Public Power Exception;" and
WHEREAS, Senate Bill 7 defines a public power utility "competitive matter" as a utility-
related matter that the public power utility governing body in good faith determines by a
majority vote is related to the public power utility's competitive activity, including commercial
infomiation, and would, if disclosed, give advantage to competitors or prospective competitors;
and
WHEREAS, the provisions of Senate Bill 7 exclude the following categories of information
from the definition of a "competitive matter":
· Information relating to the provision of distribution access service, including the terms
and conditions of the service and the rates charged for the service but not including
information concerning utility-related services or products that are competitive;
· Information relating to the provision of transmission service that is required to be filed
with the Public Utility Commission of Texas, subject to any confidentiality provided for
under the roles of the commission;
· Information for the distribution system pertaining to reliability and continuity of service,
to the extent not security-sensitive, that relates to emergency management, identification
of critical loads such as hospitals and police, records of interruption, and distribution
feeder standards;
· Any substantive rule of general applicability regarding service offerings, service
regulation, customer protections, or customer service adopted by the public power utility
as authorized by law;
· aggregate information reflecting receipts or expenditures of funds of the public power
utility, of the type that would be included in audited financial statements;
· Information relating to equal employment opportunities for minority groups, as filed with
local, state, or federal agencies;
5
· information relating to the public power utility's performance in contracting with
minority business entities;
· Information relating to nuclear decommissioning trust agreements, of the type required to
be included in audited financial statements;
· Information relating to the amount and timing of any transfer to an owning city's general
fimd;
· Information relating to environmental compliance as required to be filed with any local,
state, or national environmental authority, subject to any confidentiality provided under
the rules of those authorities;
· Names of public officers of the public power utility and the voting records of those
officers for all matters other than those within the scope of a competitive resolution
provided for by this section;
· A description of the public power utility's central and field organization, including the
established places at which the public may obtain information, submit information and
requests, or obtain decisions and the identification of employees from whom the public
may obtain information, submit information or requests, or obtain decisions; or
· Information identifying the general course and method by which the public power
utility's functions are channeled and determined, including the nature and requirements of
all formal and informal policies and procedures; and
WHEREAS, the City of Denton, a Home-Rule city, and a municipal corporation, in the State
of Texas, owns and operates a municipal electric utility; and
WHEREAS, the Denton City Council, as the governing body of the municipally-owned
electric utility, desires to adopt this RESOLUTION defining "competitive matter" for the
purpose of protecting the competitive position of its electric utility, Denton Municipal Electric
("DME") as provided for in Senate Bill 7; NOW, THEREFORE,
THE COUNCIL OF THE CITY OF DENTON HEREBY FINDS AND RESOLVES:
SECTION 1: That the following activities constitute "competitive matters" that are
related to present and future competitive activity of the electric utility, and that would, if
disclosed, provide advantage to existing or prospective competitors:
A. Financial Information, including but not limited to:
· Financial planning, sensitivity and scenario analysis;
· Rate and pricing strategies, studies and targets;
· Revenue and expense projections and targets;
· Historical and projected fuel pricing, purchases and usage;
· Fuel and purchased power hedging/risk management strategies;
· Cost of services studies;
· System valuation studies and related information
· Cash flow projections
· Internal audit reports
· Debt allocation and debt refunding strategies
B. Purchasing and Contract Information, including but not limited to:
· Power purchase pricing, proposals and contracts;
Power sales pricing, proposals and contracts;
· Fuel purchase pricing, proposals and contracts;
· Fuel transportation pricing, proposals and contracts;
· Purchasing information, including bids, proposals and contracts;
· Negotiations, modeling, data, correspondence, drafts and memoranda related to
negotiations and considerations of the above contracts and pricing;
· Information or data related to firms supplying goods or services related to Denton
Municipal Electric;
· Alliance, joint venture and aggregation information.
C. Business Operations Information, including but not limited to:
· Corporate strategic and business plans;
· Consulting reports;
· Work management studies;
· Benchmarking studies;
· Personnel compensation;
· Divestiture or acquisition plans and strategies.
D. Generation/Transmission/Distribution System Operations Information, including but not
limited to:
· System improvement evaluations and recommendations, including economic evaluations;
· Generating unit operating and performance data including heat rates;
· Engineering and design of generation units and transmission/distribution system;
· Control system design and capabilities;
· Maintenance schedules;
· Unit dispatch and system outage information;
· Load forecasts;
· Generation/transmission/distribution system improvement plans and work papers;
· Generation unit and system audits;
· Transmission and distribution system loading characteristics and capabilities;
· Target electric generation and production levels.
E. Sales, Market Research and Marketing
· Market research studies;
· Marketing strategies, plans and budgets;
· Sales and promotion strategies;
· Incentive programs.
F. Competitive Customer Information, including but not limited to:
Customer lists or identification data;
·Customer energy pricing, sales and revenue information;
Customer non-energy pricing, sales and revenue information;
· Customer load profiles.
SECTION 2: That all of the declarations and findings contained in the preamble to this
}esolution are made a part hereof and shall be fully effective as a part of the subject matter of
this resolution.
SECTION 3: That consistent with the identification of such competitive matters, the
City Council declares confidential all documents and other information concerning such matters,
and will determine on a case-by-case basis as to the specific activities within the scope of such
identified matters whether deliberations and action by the City Council will be undertaken in an
executive session or not.
SECTION 4: That the City Council reserves the right to supplement or amend the list of
competitive matters set forth in this resolution by the addition or deletion, or case-by-case
determinations as may be desirable in order to continue to operate and manage the City of
Denton's electric system in a manner consistent with the interests of the City and its electric
ratepayers, in accordance with the provisions of applicable law, expressly including, without
limitation, the protections authorized by Senate Bill 7.
SECTION 5: That if any section, subsection, paragraph, sentence, clause, phrase or
word in this ordinance, or application thereof to any person or circumstances is held invalid by
any court of competent jurisdiction, such holding shall not affect the validity of the remaining
portions of this ordinance, and the City Council of the City of Denton, Texas hereby declares it
would have enacted such remaining portions despite any such invalidity.
SECTION 6: That this resolution shall become effective immediately upon its passage
and approval.
PASSED AND APPROVED this the day of ., 1999.
JACK MILLER, MAYOR
ATTEST:
JENNIFER WALTERS, CITY SECRETARY
By:
APPROVED AS TO LEGAL FORM:
HERBERT L. PROUTY, CITY ATTORNEY
S:\Our DocumentshO, esolutions'O9\l)ra~ 2 DME SB7 Competitive Matters Res.doc
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PUBLIC POWER EXCEPTION
OPEN MEETINGS
Sec. 551.086. CERTAIN PUBLIC
POWER UTILITIES: COMPETITIVE
MATTERS. (a) Notwithstanding
anything in this chapter to the contrary,
the rules provided by this section apply
to competitive matters of a public power
utility.
(b) In this section:
(1) "Public power utility"
means an entity providing electric or gas
utility services that is subject to the
provisions of this chapter.
(2) "Public power utility
governing body" means the board of
trustees or other applicable governing
body, including a city council, of a
public power utility.
(3) "Competitive matter"
means a utility-related matter that the
public power utility governing body in
good faith determines by a vote under
this section is related to the public power
utility's competitive activity, including
commercial information, and would, if
disclosed, give advantage to competitors
or prospective competitors but may not
be deemed to include the following
categories of information:
(A) infoi-iitation
relating to the provision of distribution
access service, including the terms and
conditions of the service and the rates
charged for the service but not including
infoimation concerning utility-related
services or products that are competitive;
(B) information
relating to the provision of transmission
service that is required to be filed with
the Public Utility Commission of Texas,
subject to any confidentiality provided
for under the rules of the commission;
(C) information for
the distribution system pertaining to
reliability and continuity of service, to
the extent not security-sensitive, that
relates to emergency management,
identification of critical loads such as
hospitals and police, records of
interruption, and distribution feeder
standards;
(D) any substantive
rule of general applicability regarding
service offerings, service regulation,
customer protections, or customer
service adopted by the public power
utility as authorized by law;
(E) aggregate
information reflecting receipts or
expenditures of funds of the public
power utility, of the type that would be
included in audited financial statements;
(F) information
relating to equal employment
opportunities for minority groups, as
filed with local, state, or federal
agencies;
(G) information
relating to thc public power utility's
performance in contracting with
minority business entities;
10
(H) information
relating to nuclear decommissioning
trust agreements, of the type required to
be included in audited financial
statements;
(I) information
relating to the amount and timing of any
transfer to an owning city's general fund;
(J) information
relating to environmental compliance as
required to be filed with any local, state,
or national environmental authority,
subject to any confidentiality provided
under the rules of those authorities;
(K) names of
public officers of the public power utility
and the voting records of those officers
for all matters other than those within
the scope of a competitive resolution
provided for by this section;
(L) a description of
the public power utility's central and
field organization, including the
established places at which the public
may obtain information, submit
information and requests, or obtain
decisions and the identification of
employees from whom the public may
obtain information, submit information
or requests, or obtain decisions; or
(M) information
identifying the general course and
method by which the public power
util/ty's functions are channeled and
determined, including the nature and
requirements of all formal and informal
policies and procedures.
(c) This chapter does not require a
public power utility govermng body to
conduct an open meeting to deliberate,
vote, or take final action on any
competitive matter, as that term is
defined in Subsection (b)(3). Before a
public power utility governing body may
deliberate, vote, or take final action on
any competitive matter in a closed
meeting, the public power utility
governing body must first make a good
faith detemfination, by majority vote of
its members, that the matter is a
competitive matter that satisfies the
requirements of Subsection Co)O). The
vote shall be taken during the closed
meeting and be included in the certified
agenda or tape recording of the closed
meeting. If a public power utility
governing body fails to determine by
that vote that the matter satisfies the
requirements of Subsection (b)(3), the
public power utility governing body may
not deliberate or take any farther action
on the matter in the closed meeting.
This section does not limit the right of a
public power utility governing body to
hold a closed session under any other
exception provided for in this chapter.
(d) For purposes of Section 551.041,
the notice of the subject matter of an
item that may be considered as a
competitive matter under this section is
required to contain no more than a
general representation of the subject
matter to be considered, such that the
competitive activity of the public power
utility with respect to the issue in
question is not compromised or
disclosed.
(e) With respect to municipally
owned utilities subject to this section,
this section shall apply whether or not
the municipally owned utility has
adopted customer choice or serves in a
multiply certificated service area under
the Utilities Code.
(f) Nothing in this section is intended
to preclude the application of the
enforcement and remedies provisions of
Subchapter G.
11
TEXAS PUBLIC POWER ASSOCIATION
FAX TRANSMITTAL LETTER
Phone # (512) 472-5965
FAX # (512) 472-5967
tO:
RE:
Number of pages (including cover):
If you do not receive all pages, or if any difficulty in transmission
occurs, please contact at (512) 472-,5965.
12
701 Braze, Suite 375
Au.~tln, Te.xa.~ 78301
Phone. (~12)
RI~SOLU/ION DI2;' TF-.P. MiNrlNG COMPETITIVE MATTERS
WHICH ARE SUBJECT TO ?ROTECTION UNDER.
THE TEXAS OPEN MEISTINGS ACT
AaND TEXAS PUBLIC INFORMATION ACT
WI-IEREAS, Senate Bill 7 passed by the Texas Legislature during its 1999 session recognizes that
municipally owned utilities require an additional degree of flexibility Ln connection with their
operations under thc Texas Open Meetings Act and the Texas Public Information Act, in
connection with the existing competitive wholesale electric market and impending competitive
retail market as the transition to an era of retail competition occurs; and
WI-I~KEAS, the City Public Service Board recognizes that its electric and gas utility operations
will be affected by the impending changes to the retail electric m~rket and will be affected by
competitive pressures from new electric suppliers, whether or not City Public Service and the San
Antonio City Council elect to implement customer choice on or alter January 1, 2002; and
WB-'F-REAS, Senate 'l~iI1 7 amends thc Texas Open Meetings Act and Texas Public Information
Act to authorize the governing body cfa public power utility such as City Public Service to
determine in good faith those areas of its operations which it deems to be "competitive matters"
related to its competitive activities, including commercial information that would, if disclosed,
provide an advantage to its existing competitors or prospective competitors; and
WI-~,~AS, after appropriate deliberations, the City Public Service Board ha~ identified, as of the
present time, those general areas wltich it deems to be "competitive matters" as contemplated by
Senate Bill 7, as well as thc potential harm to the city's competitive position a~d the nature of the
potential advamage to e~.st[ng or ?ro~pective competitors in the event deliberations and actions
of the City Public Service Board with respect to ~uch matters are required to be open to the
public, and in the event information relating to such matters is required to be released upon
request made pursuant to the Texas Public Information Act
NOW= TI-IF. REFORE gE iT RESOLVED:
The City Public Serv/ee Board in the exarci~qe of good faith and cognizant
o£its fiduciary duty in mana~ng and operating the City of San A.ntonio'~ electric
and gas sy~tem~, hereby det~rmine~ that the activities listed on Exhibit A attached
to this resolution con~irute "competiriv~ matters" because they arc related to
present or future competitive activity of City Public Service, and that, for the
rea~on~ including but not lira/ted to those set out as to each matter, would if
disclosed provide advantage to existing or prospective competitors of City Public
Service. None of the matters included in Exhibit A ~e intended to encompass any
of thc thirteen subjects e~cluded from the deaqnitlon of "competitive matters"
pursuant to Sections 552.131 (a)(3) and 55 !.086(b)(3) of the Texas Oovernment
Code.
S005121?.WI'D:
2. Consistent with the identification of~uch competitive matters, the City
Public Service Boo. rd declares confidential ali documents and other information
13
B
concerning such matters, and delegates to City Public Service start'thc
responsibiliit5, ct' d~tea'mining those documents and other information which are
reasonably rel.~ed 'co such matters and of seek-lng to preserve their confidentiality
through the procedures provided tot by the Public Int'orm~fion Act.
3. The Cfty Pt~blic Service Board will determine on a case-by-case
basis as to specit~c activities withha the scope of such identified matters or
other such matters hereafter deemed to be competitive matters, whether
deliberations and action by the City PubIic Service Board will be
undertaken in an executive session.
4. The Cky Public Service Board reserves the right to supplement or amend
thc list of competitive matters set out in this resolution from time to time by
addition or deletion or case-by-case determinations as ma)' be appropriate -',nd
desirable in order to continue to operate and manage the San Antonio electric and
gas systems hi a mariner consistent with the interests of the City and its energy
ratepayers, and ,~4th the protections authorized by Senate Bill 7.
14
Competitive Information
I. Energy Supply
A. Fuel
1. Contracts and/or Proposals for Fuel Supply, Transportation & Storage
Description - Contracts and/or proposals for fuel supply, transportation & storage including all
fuels and fuel cost components.
Rationale - Establishes level CPS may be willing to pay for fuel or energy; could provide
wholesale or potential retail competitors with information allowing negotiating advantages.
2. Fuel Price Hedging and Risk Management Program Data
Description - Certain data included in the hedging pro~arn that reflects CPS fuel/pricing
positions.
Rationale - CPS' fuel pricing, quantities and position data included in hedging contracts and
mater/als would provide information to competitors which could allow CPS production costs to be
calculated and used to competitors' advantage.
Fuel Pricing (Historical & Forecast)
Description - Historical fuel price information as well as forecast of fuel prices.
Rationale - Historical fuel price information establishes CPS' fuel acquisition practices and
strategies. Force,ts &fuel pr/ce establishes what CPS may be willing to pay tbr fuel or energy
and could benefit competitors seeking to undercut CPS prices.
Fuel Usage (Historical & Forecast)
Description - CPS' usage of fuel, both historical and forecast.
Rationale - Indicates the planned need for fuel at CPS, and may lead suppliers to engineer ways to
price services at levels above market prices, thus placing CPS at a competitive disadvantage
compared to other market participant&
Competitive Fuel Price Information
Description - Competitive market inreI[igence regarding fuel prices that is gathered and analyzed
and ukirnately used to forecast fuel prices.
Rationale - Establishes level CPS ma)' be willing to pay for fuel or energ-y. Information is
expensive to maintain and making it available ro competitors gives them that advantage at no cost
or nominal cost.
Stored/Reser-,'e Fuel Supply
Description. The amount of stored or reserve fuel supply.
Rationale - Fuel Requirements fluctuate due to deliveries and consumption of other fuels.
Information may suggest how much CPS need, the fuel and place competitors in a position to
block or bid up fuel supplies.
Budgets for Fuel Purchases
Description - Budgets of qu~tities and dollar~ that CPS anticipates purchasing.
Rationale - indica:es the pr-tuned need for fuel at CPS, and may lead suppliers to engineer ways to
price services at levels above market prices, thus providing competitors with fuel and en~gy sales
market advantages.
Actual Fuel Purchases
Description s Documentation regarding actual fuel purchases made by CPS that may include
pricing information, including cash vouchers, invoices, etc.
Rationale - Establishes amount CPS actually paid for fuet, thus providing comp~tors with a key
cost clement for CPS's energy productien costs.
S0052943W51:
B. Generation
1. Generating Unit Design, Operating and Performance Data
Description - Unit production cost and performance information ~ heat rates, variable and ftxed
O&M costs, forced outage rates, high and low capaci~ limits, ramp rates, minimum up and down
t"imes, st~rt-Ltp costs, etc.
Rationale - A unit's design, operating and performance data gives competitors valuable
information in determining CPS' production costs. AcmaI and design performance information
should be confidential.
2. Maintenance Schedules
Description - Planned maintenance schedules for all units.
Rationale - Establishes CPS need for fuel and energy during maintenance periods, thus making
CPS vulnerable to competitor planning and supplier pricing of energy resources.
Capital Improvement Plans & Strategies
Description - Any data pertaining to the CPS Generation Plan, such as units and fuel ~ypes being
considered, new plant design information, estimated cost to build, proposed timing of new plant
addition, potential acquisitions, potential divestitures, etc.
Rationale - Provides competitors with information on future additions to the capacity, and ener~
markets, allowing them to plan their own strategies in ways that may disadvantage CPS.
Competitive Bench.marking Information
Description - Competitive Bench marking information against other plants and utilities.
Rationale - Eszablishes operational advantages (or disadvantages) over other utilities and
evaluation of competitive m~ke~lace used by CPS to establish market prices. Disclosure could
benefit competitors :o CPS's detriment via marketing campaigns, direct communications of large
CtlStom ~r5, OtC.
Oenerating Unit Dispatch & Outage Information
Description - Generating Unit dispatch and outage information, what units we plan to run and
what units actually n.m.
Rationale - Determines surpius and sho~'Jge~ of energy. May be used by suppliers to extract
higher fees fi.om CPS than established by the market, thus disadvantaging CPS vis-a-vis
competitors in the energy market.
Critical Non-Fuel Procurement Activities
Description - Contracts for goods and services which are critical for power generation, especially
large procurement contracts and stxategic vcmdor alliances.
Rationale - In.formation regarding critical procurement activities can provide competitors with
det,liled cost information for key aspects of power generation, and it could also compromise
negotiations with other suppliers.
e
o
C. Wholesale Power
1. Contract Materials and;or Proposals for Purchase and/or Sale of Wholesale Power
Description -Development Documents leading toward Purchase & Sale agreements and proposals
for energy, capacity, tolling, ancillary serv'ices, t~ancial and/or physical hedging transactions, and
any other a~eements for ~holesale energy services. Final executed agreements are not included,
except where both parties a~ee that pricing provisions or other key terms should be maintained as
confidential in order to preserve competitive advantages to eithm- or both parties.
Rationale - Development documents leading toward contracts and a~eements with other parties if
~isclosecl prior consummation of a transaction have the potential to jeopardize the transaction in
the hands of competitors. Likewise, pricing provisions or other key terms may be justifiably
maintained as confidential under circumstances where both parties believe disclosure will provide
adv,'mtages to a competitor. In addition, pricing constitutes a major component of CPS's
production costs, which are competitively sensitive.
2. Pricing Strategies
Description - Pricing strategies used to secure highest market rates for CPS supplied sc-trices and
lowest prices for CPS required services.
$0052943.W5l:
16
RationaLe - Competitors could use information to thwart CPS efforts.
Sales & Revenues (Historical & Forecast)
Description - CPS' historical and future expectations of sales ~nd revenues.
Rationale - Competitors could use information to target CPS wholesale customers and attempt to
win their business. Aggregate information of a type included in CPS audited financial statements
is excluded.
Competitive Wholesale Power Price Information
Description - Accumulated t~ansaction data and market intelligence.
Rationale - Forms basis for CPS marker price expectations and represents commercially valuable
information that competitors should not be able to acquire fi.om CPS at no cost or nominal cost.
Alliances and Joint Ventures for Wholesale Power Generation and/or Sales
Description - Strategic information relating to business alliances and information relating to
negotiations with a potential business parmcr for purchase of business assets, performance of key
services, cooperative energy dispatch arrangements, etc.
Rationale - Potential parmers often w/Il not make information available to CPS if it is not
protected. Disclosure v,'ould provide competitors with information not available through other
sources which could benefit their own marker strategies to CPS's detriment.
D. Acquisition, Disposition or Exchange of Generation-Related or Fuel-
Related Assets
1. Generation facilities and critical equipment
Description - Purchase, sale, lease or exchange of generation facilities and critical equipment that
is needed to generate power.
Rationale - Establishes CPS's cost of generation regarding those a~sets, ~,hich if released could
provide competitors with key information allowing a market advantage.
2. Property
Description - Information relating to p~rchase, sale, lease or exchange of property that is for the
purpose of securing a fuel supply, new or existing power generation facilities, transmission or
distribution facilities, or other system in~asrrucmre. Final executed agreements and evaluation
materials following execution or transaction completion are excluded, subje~ to other competitive
matter protections under this policy.
ILationale - Contains information on alternatives available to CPS and terms that may be agreeable
to CPS. May include information about CPS interest in surrounding or simi.lar properties. Such
transactions may divulge information of a strategic value to CPS which could benefit a competitor
in its own strategic planning if disclosed..
Aggregate information ora type included in CPS audited f'mancial statements is excluded from items 1 and 2.
II. Retail Activities
A. Customer Information
Description. All information regarding retail customers, including information that is currently
part of the Customer Master File which constitutes the CPS Customer Information System, as well
as separate databases such as the Key Accoun~ database which includes contact management
information that is specific to each of our largest energy custom:rs.
Rationale - Information regarding retail customers can be used by competitors to target CPS retail
customers based on their usage, operating characteristics, location, rate classification, or any other
feature, whether indi~,idually or for aggregation purposes, or to exert pressure relating to the
decision of adoption of customer choice
17
S0052943w51-
B. Sales & Marketing
1. Energy Retail Sales & Revenue Information (Historical & Forecast)
Description - Retail sales and revenue information for retail gas and electhcity sales to individual
customers. Ag~egate information ora .type included in CPS audited financial statements is
excluded.
Rationale - Retail sales and revenue information for energy sales to individual customers or
narrowly-del'rued groups of customers could provide cotupetitors with valuable information for
targeting CPS' most valuable retail customers.
2. Non-Energy Retail Sales & Revenue Information (Historical & Forecast)
Description - Sales and revenue information for non-energy retail products and services that CPS
currently offers such as Budget Payment Plan (BPI>), Pre-Authorized Electronic Payments (PEP),
and All Night Securi~ Lights (ANSLs), and non-energy ret, ail products that CPS may offer in the
furore such as whole house electrical surge protection, flood lighting, green retail pricing, carbon
monoxide detectors, Internet access, home security monitoring, billing information services, data
transport sen4ces, etc. Aggregate i~formation ora .type included in CPS audited financial
statements is excluded.
Rationale. Retail sales ,and revenue information for non-energy products and sep,-ices could
provide competitors insights to which products and/or set,,'ices are valued by CPS' retail ener~
customers, and which ones could be used to entice CPS' retail energy customers to ~witch energy
suppliers.
3. Sales and Promotion Strategies, Plans & Budgets (Historical & Forecast)
Description - Information regarding sales and promotion activities for retail
sales. Such activities include advertising carnpai~s, promotional pricin~ campal,~s, and
cooperative promotions with other organiz.-tions.
Rationale - Competitors can use this information to subvert CPS retail sales
efforts and to §au~e thc effectiveness of CPS sales a~d promotion strategies.
4. Contracts and/or Proposals for Sales and Promotion Pro,rams
Description - Contracts and proposals for Saks and Promotion progrmms
Rationale - Terms and conditions specified in contracts ~nd ~opos~ls typically include detailed
information re§a.rdin~ the s~rategies, plans and budgets for sales and promotion programs, and this
Luformation can be used by competitors to a~sess the effectiveness of CPS sales and promotion
efforts in retaining and/or acquiring new retail customers.
Contracts and/or Proposals for Retail Sales
Description - Contracts for retail energy ~ales from CPS to individual customers or ~'oups of
customers.
R~tiona!c - Establishes the terms ~d conditions that CPS is wil;ing to offer for retail energy sales.
Competitors can use this information to undercut CPS offers to new retail customers.
Commission-Based Sales Incentive Plan~
Description - Sales incentive programs that are directly related to ~ales or revenue tbr retail energy
and non-energy products a.qd services.
Rationale -Such programs might be developed for retail products and services. Information
regarding employee performance relative to such pro,ams would indirectly provide information
regarding sales and/or revenue generation from retail products and services.
C. Market Research
1. Market Research Studies
Description - Market research studies related to retail activities.
Rationale - Market research studies related to retail s,~les activities provide information that is
needed to successfully market to retail customers; dlsclosure of this infonmation to competitors
would provide them with a marketing advantage at CPS's expense, Ooth by entrancing their own
knowledge of CPS target market conditions and suggesting to them the direction of CPS's market
interests. Examples of this type of i/fformation include market research related to: customer
satisfaction and loyalty; customer awareness and perception of corporate and competitor br~d
$¢0529~3,w51: 1 8
o
image; customer values and switching behavior; customer awareness, understanding and
perception of issues related to retail aspects of the electric industry; customer perceptions of retail
products and services including various attributes of products and set, ices and price; and,
customer perceptions of retail sales and promotion activities and strategies.
Proposals for Market Research Studies
Description - Proposals for market research studies related to retail activities.
Rationale - Proposals for market research studies typically include detailed information regarding
the methodology, and scope 0fproposed market research activities, and this information can be
used by competitors to gain insights to CPS retail strategies and plaxmed activities.
Marketing Research Strategies, Plans & Budgets (Historical & Forecast)
Description - Information regarding marketing research s~'ategies, plans and budgets related to
retail sales.
Rationale - This information would pro,~ide competitors with insights to CPS' strategies and plans
for retaiI products and services.
Secondary Market Research Data
Description - Secondary market research data is avaLlable for purchase or for licensing fi.om a
number of organizations such ~ Dun & Bradstreet, Aexiom, £xperian, and many others who
specialize in gathering, processing and selliag such information. Secondac~ market research data
Includes demographic, psychographic, and femographic (business) information which is gathered
from a variety of existing data sources such as credit card companies, financial institutions,
product warranty registrations, public records, magazine subscriptions, etc
Rationale - Secondary market research data can be used for direct marketing to retail customers;
for analyzing and assessing the potent/al size for retail markets; and for developing retail
marketing plans ,'md strategies. Competitors should not be allowed to benefit by obtaining at
nominal copying cost expensive research material available for commercial purchase; nor should
they be pun mitred rka'ough use of such material to identify market segments utrgeted or under
consideration by CPS.
D. Product/Service Development & Pricing
1. Business Plans for Retail Products and Services
Description - Business plans include detailed information: analyzes, sales a~d promotion plans
and strategies, and producVservice partner a~eements for new or modified offerings of retail
products and services.
Rationale - Disclosure of this mater/a}~ v, hich establishes CPS's pi,ms for offering retail products
and ser~,'ices including expec'ted sales and revenues, pr;a'nary and secondary market research
related to the product or service offering, and product or service cost information, could provide
significant strategic advantage to competitors.
2. Competitive Market Intelligence for Retail Products and Services
Description - Includes primary and secondary, market research related to retail products or services
to assess their performance in the market place.
Rationale - Gathering competitive maxket in:elligence for retail products and services is costly and
time consuming, but after this information is gathered it provides a competitive advantage for
developing competitive strategies and comper2ng in markets for products and services. Disclosure
would benefit competitors by providing them the intrinsic value of the harelligence as well as
insights in:o CPS planning.
M~rket Research Related to Development of Retail Products and Services
Description - Market research related to customer preferences for potential retail products or
services, or preferences for certain am-ibutes or key features of potential products or services.
Rationale - Market research for product development provides an enhanced understanding
customer preference~ tow'ards potential products mqd services or key features or attributes ofnew
products or services. Disclosure of information developed by CPS regardhag customer
preferences for ret,ail producta and services would pro,4de ex/sting and potential adversaries a
competiti,~¢ advantage ha the market place.
4, Retail Pricing Plans & Studies
soo529a3
19
Description - Plans, studies and detailed analyzes regarding retail pricing for energy and non-
energy products and services
Rationale. Establishes CPS' cost structure and margin on retail products and services which can
be used by competitors to undercut CPS offers to retail customers.
Energ7 Load Research
Description - Energy load research for individual customers or groups of customers which
provides information regarding their energy load profile.
Rationale - Energy load research provides information regarding customer's ener~' load profile
which is critical information for retail pricing. Energy load research is costly, and this
information provides a competitive advantage to companies that have access to it,
E. Supply Contracts/Arrangements for Retail Products and Services
1. Wholesale Energy Supplies
Description - Supply contracts or intra-company transfer arrangements for supply of wholesale
energy that CPS will sell at retai[.
Rationale - Wholesale ener~ supply contracts or inn-a-company transfer arrangements for
wholesale energy include detailed information regarding price and other terms and conditions
which would provide competitors critical information that could be used to undercut CPS offers in
the retail market.
2, Non-Energ'y Products and Services
Description - Contracts for supply of non.energy products and services that CPS will sell at retail.
In some cases contracts for non-chert' products and services ate referred to as "product pa,"mer
contracts" because CPS simply provides the retail marketing channel for s,"de of the third-party's
product or service along with CPS' energy products.
Rationale - Supply contracts for non-energy products and sew'ices contain detailed in~'ormation
regarding price as ,,*'ell as terms Md conditions which would provide competitors with critical
information that could be used to undercut CPS offers in the retail market.
III. Corporate Planning & Strategy Information
1, Corporate Business Plan
Description - Bus/ness plans include detailed information, analyzes: plans and strategies, and
producv'service parmer a=mcemcmts for new or modified offerings of retail products and services.
Any substantive rule of general applicabiliw regardJ, ng service offerings, service regulation,
customer protections, or customer service adopted by CPS is excluded.
Rationale - Shows CPS competitive strategies and long range plans. Would allow competitor
advance notice of CPS actions,
2. Acquisition Assessments
Description - Assessments, plans and strategies mlatcd to acquisition of other utilities.
Rationale - Shows CPS m'ategy and could allow other entit%s to preempt potential acquisitions by
counter offering or overbidding CPS offers_
3. Debt Allocation and Debt Refunding Strategies
Descr/ption - CPS strategies and studies on debt allocations or refundings as well as potential debt
offerings.
Rationale - Knowledge of these V/pcs of ~ansac6ons/plans could give competitors insight into
CPS pricing and marketing strategies.
4, Executive Pay and Perquisites
Description - Information regarding executive pay and perquisites beyond ,,hat i$ required to be
disclosed by SEC re_.m.~lations for investor ovencd utilities.
Rationale - Could allow competitors to assess potential offers to attrac~ key CPS personnel.
5. Internal Audit Reports
20
S00529t3 W::; 1:
o
Description - Those poixions of internal audit report~ containing information relar/ng to
competitive matters.
Rationale - The scope of'CPS internal auditing program covers all CPS functions and activities.
Those portions of all such reports that cover matters identified as competitive in nature would, if
disclosed, provide competitors with information about CPS strategies and plans.
6. Consulting Reports
Descr/ptiou - Internal consulting reports include all repons developed to review the performance
of CPS functions and activities that are otherwise defined as competitive in nature.
Rationale - Ail in~ernal consulting reports that cover matters identified as competitive in nature
would likewise contain information on CPS strategies and plans, which could disadvantage CPS if
known to competitors.
Internal Audit and Consulting Work Papers
Description -Those portions of internal audit consulting project work papers that include
correspondence, field notes, documents and analyzes developed to audit or review the CPS
functions and activities that are othera~ise defined as competitive in nattaz.
Rationale -Ail information included in ~nternal audit and consulting reports and information used
to develop such repons that cover matters identified as competitive in nature could, if released,
provide competitors with direct information regarding CPS competitive strategies.
Corporate Inventions/Innovations
Description - Inventions include, but are not limited to, hardware, softwaze, tools and pi'ocessing
methods.
Rationale. Shows CPS competitive strategics and propr/etary technologies. Would allow
competitors to utilLze results of CPS research and design efforts without investment_
Financial, Accounting & Statistical Data Submitted Voluntarily and Confidentially to
Industry Groups, to the extent containing information regarding Competitive Matters
Description - Data submitted to APPA, IPPA. AGA or another industry group wkich pertains to competitive
Rationale - Competitive information included in data submitted under confidentiality
arrangements with third panics, if released, could benefit competitors in ~he same ~'ay as direct
information relating to such matters.
10. Supplier Information
Description -. Data related to fwms supplying CPS goods and services.
Rationale - Competitor insight into CPS purchasing habiu and identity of suppliers on which CPS
heavily relies to supply necessary goods ~d services could provide significant advantage.
Engagement,'use ....ora particular supplier could indicate types of strategic moves CPS is pl~mning
or lmnatmg.
11. Corporate Cash Flow Projections
Description - Projections of CPS revenues, expenditures and funds available for
in','estment and services, excluding ag~egate information ora type that would be included in
audited t'mancial statements.
Rationale - Disclosure of such inforrnaion would show CPS's competitive
stren~h or weakness £mancially in near-term competitive scena~qos, '.including ability to meet
competitive price reductions by others, abili~ to acquire assets or operations, and others.
12. Business Unit Financial Statements
Description - Projections of CPS revenues, expenditures ~d net income for the
Business Units. Excludes aggregate information of' a D:pe that would be included in audited
financi~ statements.
Rationale - Disclosure could benefit competitors by showing competitive
s'a'ength or v, eakness of the business unit and reflecting its ability, or inability to conduct
acquisitions, mount new competitive programs, or expand into additional markets.
S0052943W$1:
21
701 BRAZO$, SUITE 375
AUSTIN, TX 78701
Phone: 512-472-5965
Fax: 512-472-5967
Fax
To:
SHARON MAYS
DENTON
From: MARKZION
EXECUTIVE DIRECTOR, TPPA
Fa~ 940-349-7334 Date: September 14, 1999
Phone: Pages: 4
Re: Operl Records Resolutions
· Sharon:
Attached is the LCRA resolution (this copy is for their affiliate, GenTex,
and an essentially identical version has been passed by th~ LCRA Board
for the LCRA in general).
CPS in San Antonio has also passed their re~olution. We will fax a copy of
it to you under separate cover later today.
Austin has not passed a resolution, but their Council may consider such
action in the near future,
Hope this is helpful, please call if you need anything else.
Thanks, Mark
22
8112/99
Page I of 3
GENTEX BOARD POLICY
PROTECTION OF COMPETITIVE ELECTRIC INFORMATION
August 12, 1999
PURPOSE
Th.is Policy establishes the policy, findings, and procedures oft. he Board regarding the protection
of information related to public power utility "competitive matters," as pro¼ded in § 552.131,
Texas Govenmaent Code (Texas Public Ir~ormation Act).
POLICY
OenTex is a generating electric utili~- authorized by la,,,,- to compete in the wholesale electric
market. GenTex has an obligation to protect information related to competitive matters in order
to successfully fulfill its mission to provide low' cost utiliD' services to @enTex customers. This
policy is intended to protect such information consistent with Senate Bill 7 and the protections
provided by section 552.131, Government Code.
FINDINGS
The Board finds that information collected, a~sembled, or maintained by OenTex m any media
.l. ha.t_is x.e.~ed m th~.£oLlo.wiag 2LsI: of marrersis, clearly.and_masonaNy related .to .GeaTex,~/awful
competmve energy service and energy market activiues, and such information would, if
disclosed, give advantage to competitors or prospective competitors of.the O~Yex. in the electric
market:
(A) Financial information, including
(1) Business -and facilities plans and budgets
(2) Capital improvement and project plans and studies
(3) Target electric generation and production levels
ffeg)' Revenue and expense projections and targets
(5) Operation and capital statements - actual to budget perforrnance information
(6) Business forecasts
(7) Strategic plans, studies and supporting documents
23
8/12/99
Paga 2 of 3
(1'2)
(14)
Cost of service studies
Rates and pricing strategies and target~
Fuel hedging and risk management sln-ateg/es
Internal business performance information
Energy and billing information
Intc~'rnal cost assignments and allocation methodology
Financial planning, sensitivity -and scenario analyses
(B) Purchasing and Contract Information, including
(15) Power supply (energy and capacity) pricing, proposals, and contracts
(16) Fuel contracts, including all terms and conditions
(17) Tranqportation deliver;,' contracts, including rail and pipeline
(18) Purchasing information, including bidders lisu, specifications, bids, proposals,
contracts and bid results
(19) Negotiations, modeling, data, correspondence, drafts, and memoranda related to
negotiations and consideration of the above contracts and pricing
(C) Business operations, including
(20) Work management studies, system configuration and system data
(21) Bench_marking data, surveys, and reports
(22) Market plans and studies
(23) Personnel stuffing and compensation
(24) Competitive IntelIigence systems and information
(25) Product design information
(D) Generation system operations, including
(28)
.. O~-r~ri~.cout:ol.~y~em de, aign aad cat~abiii~s
Generation unit and elec~c generation system maintenance and outage schedules
. Generation unit, generation:$ymem, and facility .construction. and project
~ent plans
(29) Generation unit and generation system operating and perfo,mance data
(30) Generation unit and generation system audits
(3 I) Engineering and design of generation units and generation
(32) System improvement evaluations ar.d recommendations, including economic
evaluations
(33) Load and generation forecasts
(34) Maintenance policies and processes
(35) Operation management planrfing information
24
8/12/99
Page 3 of 3
Information or records, in any media, of GenTex that are reasonably related to competitive
matters described above are excepted from the disclosure requirement~ of Chapter 552 of the
Texas Government Code.
From time to t/me, the GenTex Board of Directors may determine that additional information is
reasonably related to OenTex's lawful competitive activities, but need not amend this policy to
do so. The policy, findings, and procedure of this Policy shall apply to such additional
information.
This Policy is not intended to apply to any in.formation excluded from the definition of
"competitive matter" enumerated in section 552.131 (a)(3)(A - M, Government Code.
PROCEDURE
The information described above shall be managed by GenTex officers, employees, and agents
as confidential, with all necessary, and reasonable man,~gement and security measures.
25
701 BRAZO$, SUITE 375
AUSTIN, TX 78701
Phone: 512.472-5965
Fax: 512-472-5967
Fax
To:
Sharon Mays, Denton
From; MARK ZION
EXECUTIVE DIRECTOR, TPPA
Date=
Phone:
Pages:
Re: Open Records cc:
· Sharon: Attached is the resolution from the City of Boeme. I have not
received copies from the others (including Lubbock and Kerrville PUB). it
appears that everyone is using basically the same approach (based on the
examples provided at our TPPA Annual Meeting) with some modifications
in the preamble. I will ask LP&L and KPUB to forward their resolutions to
us and will send them on to you, Please call if I can be of help, Ma~k
26
RESOLUTION NO. 99-R35
A RESOLUTION DEFINING "COMPETITIVE .MATTER"
FOR TI~ PUI~OSE OF PROTECTING THE COMPETITIVE
POSITION OF THE CITY OF BOERNE ELECTRIC AND
GAS UTILITIES AS PRO.VIDED FOR IN SENATE BILL 7
WHEREAS, Senate Bill 7 enacted into law by the 76'h Session of the Texas Legislature and
~igned by the Governor on June 18, 1999, with an affective date of September 1, 1999, amends
Subchapter C, Chapter 552, Government Code, by adding Section 552.131 to provide a new
exception to disclosure for public power utilities competitive matters; and
WHEREAS, Senate Bill 7 defines "competitive matter" as a utility-related matter that the
public power utilities' governing body in good faith determines by a majority vote is related to the
public pov,?r Utilities' competitive activity, including commercial infow-,ation, and would, if disclosed.
give advantage to competitors or prospective competitors; and
· . WHEREA'8, the City.0fBoerne;'
Texas, ow,ns and operates municipal ele~
· )_ '-..- WHEREAS, the City Council of th
owned electric and g~s utilities, desires to
pr~rpose o£protecting thc competitive posi
Bill 7;
NOW THEt~EFORE, BE IT RE:
BOERNE, TEXakS:
PART f: Competitive Matter (he
552.131 of the Govemm'ent Code, whk
utilities competitive matters, th~ follo~
Council of the City of B0erne, in the exert
ofwMch would give advantage to comp,
A. Financial information, in(
1-. Business and fad
!.. Capital improven
3. Revenue and exp
4. Operations and ce
5. Business forecazl
6: Strategic plans, s
7. cOst of service st
8. Rates and pricin~
9. Internal business
10. Energy and billi~
1 t. Internal cost assil
12. Financial plannit
7exas, a home-rule municipal cti.rporation, in the State of
tric and gas utilities; and
~ City. of Boeme, as the governing body of the municipally
dopt.this Resolution defining "competitive matter" for tb.e
:ion of its electric and g-as utilities as provided for in Senate
·
rmn so called): For th purposes of pp ~ auon o ~c n
h provides for exception to disclosure for public 1: ower
ng categories of information are determined by ~e City
ise 9fgood faith, to be Competitive Matters, the discl ,sure
~titors or potential competitors: '
:luding but not limited to:
ities plans and budgets
ent and project plans and studies
rose projections and targets ' ~ '
sPitat statements; actual to budget performanqe inforr~ation
udies and supporting documents ·
~dies
strategies and targets,
aefformance information
: in.formation
nment and allocation methodology
[, sensitivity'and scenario analysis
27
13. Fuel pricing and us;
14, Fuel hedging/risk n
15. Operation and capil
Purchasing and Con~ract Ir
5.
6.
7.
8.
Power supply prici:
Purchasing infomm
contracts and bid r~
Negotiations, mod,
to negotiations an¢
Power sales pricin
Fuel contracts and
Fuel pricing and u
Power purchase c(
Fuel transportatim
Business operations, inch
1. Work managemer
2. Benchmar 'king da'
3. Market plans and
4. Personnel, staffml
5. Competitive intel
6. Product design in:
7. Cost of service s~
8. Internal business
9. Energy and bitlLn
10. Internal cost assi~
11. Financial plarmin
12. Competitive intel
13.
14'. '"
15.
~anagement strategies
al statements-actual to budget performance informa
formation, including but not limited to:
~g, proposals and contracts
:ion, including bidders list, specifications, bid~s, propoIlals,
,suits ; i ,1
ling, data. correspondence, drafts ahd memoranda related
considerations of the above contracts and pricine
, proposals and contracts
}roposals
~ge
at, acts and proposals
pricing and contracts
:ling but not limited to:
t studies, system config~ation mud system data
a, surveys and reports
;tudies
~ and compensation
igence systems and information
'ormation
rd/es
>erform~nce information
=, information
nments and allocation methodology
~, sensitivity and scenario analysis
.igence systems and information
Product design in [ormation
Forecast of sales Md revenues
Sales and promction strategics, plans, contracts, proposal* and bt
'ecast)
osals for retail energy sales
ans
contracts, proposals and budgets rcga. rd~ng mari
(historical and fo
16. Contracts or pro[
l 7. Sales incentive p
18. Strategies, plans
research
19. Strategies, plans,
and marketing ~
development of ':
20. Research rcgardi
21. Corporate busim
22. Assessments, pl~
23. Strategies, plans
24. Internal audi~ re
contracts, proposals m~d badgets regarding analysis
md promotion of retail products and services.
.ag energy loads
dgets
feting
sales
~r the
ss plans
ns or strategies related to acquisition of other utilities
or studies regarding debt allocation or reftmding
28
25. Reports, sununarie:
employment prcre~
26. Consulting reports
27. Financial, account
groups or other thi:
28. Information or date
municipally owme¢
29. Alliance, and joint'
D. Competitive Customer Irt
1. Customer lists or
data
PART 2: Intbrmation or record,
related to a Competitive Matter as deft
requirements of Chapter 552 of the
PART 3: The City Council ofth~
the list of Competitive Matters set out in
case-by-case determinations as may be a
manage the City of Boeme electric and g
City and its electric and gas utilities custo
PART 4: Notwithstanding any,
Competitive Matter an), matter exclude<
Section 552.131 (a)(3) (A-M) of the
PASSED and APPROVED this'
; or otller documentation describing executive pay
aisites
ag or statistical data submitted con!~dent~ally to ind~
d parties regarding competitive matters
related to firms supplying goods or services related
utility
tenture and ag~egation intbrmation for power gener~
)rmation :
ratification da-m, consumption data, or rate.,q2illing/ac~
md
ATTEST:
-~ity,~3ecretary
stry
the
2tort
29
APPROVED:
Mayor
of the City of Boeme, in any media, that axe reasoriab!y
.ed in PART 1 above are excepted from the disch ~sure
mment Code.
City of Boeme reserves the right to supplement or a ~end
his Resolution from time to time by~ addition or deleti on or
,propriate and desirable in order to continue to opcrat: and
ts utilities in a mariner consistent with the interests fthe
a~ers, and '~,-ith the protections authorized by Senate Bill 7.
mumeration otherwise, this Resolution shall not de~lm as
from the definition of "competitive matter" descril~ed in
;mment Code.
he 26" day of October, 1999.
24 TexReg 11294 December 17, 1~ Texa~ ReglU~r
Agenda Item.
Date
AGEN))A INFORMATION SHEET
AGENDA DATE: April 11, 2000
DEPARTMENT: Utility Administration
ACM:
Howard Martin, 349-8232
SUBJECT:
Receive a report, hold a discussion and give staff direction concerning dually certified service
areas between the City of Denton and Argyle Water Supply Corporation.
BACKGROUND:
The City of Denton's existing water and wastewater service area or Certificate of Convenience
and Necessity (CNN) was first established by the TNRCC in 1979. This service area is referred
to as CCN Number 10195. Subsequent adjustments were made to Denton's CCN in the area
south of the Lake Roberts Dam to add to Denton's CCN and later to decertify portions of this
area to Bolivar Water Supply Corporation. The current CCN held by Denton includes dually
certified areas with several small water systems that were developer created water systems
(Vacation Village, Spring Hill, Powell Farm, Terra Southwest ect.). Denton's CCN also has
dually certified area with three expanding rural water supply corporation (Bolivar WSC,
Bartonville WSC and Argyle WSC). Argyle and Bartonville WSCs are current wholesale water
customers of the Upper Trinity Regional Water District (UTRWD) and likely to expand rapidly
due to their access to treated surface water supplies and their strategic location within Denton
county.
Argyle WSC and the City of Denton have enjoyed a positive and cooperative working
relationship for many years. As the Argyle WSC has slowly expanded over the years they have
established a significant customer base within the dually certified service areas shared with the
City of Denton. The existing CCNs for Denton and Argyle WSC along with the city limits for
Argyle and Denton are shown on Exhibit I. Most of this dually certified service area was outside
the Argyle city limits but was within Denton's Extra Territorial Jurisdiction (ETJ). Water
service was provided by Argyle WSC by consent from the City of Denton with septic tanks used
for wastewater treatment. This arrangement was driven by the relative availability of water
service by Argyle WSC and the long distances and associated costs to extend water and
wastewater service from the City of Denton. This service area has no existing wastewater
services and includes several major Argyle WSC facilities including groundwater wells, ground
storage and booster pump stations and the UTRWD surface water delivery point.
More recently, the City of Denton annexed a proposed development along Hwy 377 called the
Hills of Argyle and provided water service to this development through a "pass through
agreement" with Argyle WSC and the UTRWD. The City of Denton's recent annexations of the
Huffines and Robson Developments have also resulted in the extension of water and wastewater
service to a portion of this dually certified service area along Hwy 377 that lies within Denton's
city limits.
Since both utilities are expanding and desire to establish defined service areas cooperatively
rather than competitively, the staff has meet to discuss service area boundaries based upon a
single certification approach. Preliminary discussions have lead to some conceptual adjustments
to the CCN boundaries as shown in Exhibit II. If these adjustments were finalized as proposed,
the resulting CCN boundaries between the City of Denton and Argyle WSC would be as shown
in Exhibit III.
Some key policy issues related to these proposed CCN boundaries that would need to be
addressed are summarized below:
1. A portion ofDenton's ETJ that lies North of the strip annex boundary between Denton and
Argyle will ultimately be annexed by Denton but would be served by Argyle WSC and septic
tanks.
2. A portion of the dually certified service area that would be decertified by Argyle WSC
contains existing Argyle WSC pipelines and customers. Options to consider would include:
· Leave these customers permanently connected to the Argyle WSC system.
· Negotiate terms and conditions with Argyle WSC to transfer these customers and related
infrastructure to Denton now or in the future.
3. An isolated service area presently served by Argyle WSC outside their CCN and within
Denton's CCN is proposed to be decertified to Argyle WSC. This area lies north of the strip
annex boundary of Denton east of the Argyle city limits.
4. An area within Argyle's city limits south of Crawford Road that has no certification status
would be certified by Argyle WSC.
Staff will provide the Board with a summary and explanation of these service areas and be
prepared to answer questions concerning these issues.
RECOMMENDATIONS:
Staff is bringing this issue to the Cit Council for information and discussion purposes only and
is requesting policy direction at this time.
Respectfully submitted:
Howard Martin ~
Assistant-City ManagerV Utilities
Exhibits: Maps of the Proposed CCN Changes Between AWSC and Denton
I. Current CCN Boundaries
II. Proposed Duel Certified Area CCN Changes
III. Resulting CCN Boundaries
,v~ ~-~ Argyte W.S.C. C.C.N.
s Areas of Adjustment
~,,~ ~,~ ~i~ EXHIBIT II
J:lArc, vi~lF~u~'~$W D~l~on CCN~.a~r
$
Scale: '1"=-1 Mile
j:~ArcvfewV=~o~.~tSW Der4on CCNs.epr
City of Denton C.C.N.
Argyle W.S.C. C.C.N.
Proposed Conditions
EXHIBIT III
TEASLEY LANE CORRIDOR TRAFFIC STUDY ADDENDUM
STAFF SUPPLEMENT
COMPREHENSIVE PLAN - MOBILITY PLAN RELATIONSHIP: UPDATE
April 11th, 2000
TEASLEY- Lillian Miller to Robinson
Year 2016:31,100 ADT [6-lane, divided]
LOS D = 30,450 ADT
LOS E = 33,000 ADT
HOBSON - Country Club to Teasle¥
Year 2016:16,700 ADT [4-lane, undivided]
LOS D = 16,405 ADT
LOS E = 18,000 ADT
HICKORY CREEK - City Limits to Teasle¥
Year 2016:21,650 ADT [4-lane, divided]
LOS D = 21,050 ADT
LOS E = 23,000 ADT
HANDOUT TO COUNCIL
4/11/00
TEASLEY LANE CORRIDOR STUDY
FINAL REPORT
ADDENDUM
Prepared for
CITY OF DENTON
Prepared by
C&P Engineering, Ltd.
TABLE 6A
Lane Needs Based on Capital Improvement Strategy
Lillian Miller: 4D 4D 4D 4D 4D 4D '4D 5D 5D
IH 35 - Teasley "A" "B .... C .... A" "B/C" "B .... C/D .... B' "C"
Teaslcy: 4D 4D 4D 4D 6D 6D 6D 6D 6D
WI 35 - Londonderry "A .... D .... E .... D .... A .... A .... B" "C .... D"
Teasley: 4D 4D 4D 4D 4D 4D 4D 4D 6D
Londonderry - Hobson "A .... A .... A .... A .... A .... A .... B .... C/D .... A"
Teasley: 4D 4D 4D 4D 4D 4D 6D 6D 6D
Hobson - Lillian Miller "A .... A .... A .... A .... C .... D .... A .... B .... C/D'
Teaslcy: 2U 2U 2U 6D 6D 6D 6D 6D 6D
Lilliaa Miller - Robinson "F .... F' "F" "A .... A .... A .... B" "C .... D/E"
Teasley: 2U 2U 2U 6D 6D 6D 6D 6D 6D
Robinson - I-livkoty Creek "B .... D/E .... F .... A .... A .... A .... A .... B/C .... C/D"
Teasley: 2U 2U 2U 6D 6D 6D 6D 6D 6D
Hickory Creek - City Limit "A .... C/D .... F .... A' "A .... A .... A .... B .... D"
Hobson: 2U 2U 2U 2U 4U 4U 4U 4U 4U
Country Club - Teasley "B .... C" "B .... B .... A .... A" "B/C .... C/D .... D/E"
Wind River: 4U 4U 4U 4U 4U 4U 4U 4U 4U
Teasley - IH 35 "A" "A' "A" "A .... A" "A" "A" "A .... A"
Ryan: 2U 2U 2U 4D 4D 4D 4D 4D 6D
Country Club - Teasley "A .... A .... A .... A .... A .... A" "C .... D .... A"
Robinson: 2LI 2U 2U 2U 2U 4D 4D 4D 4D
Teasley - Harvard "A" "A .... A .... A .... C .... A .... A .... A .... B/C"
Hickory Creek: 2U 2U 4D 4D 4D 4D 4D 4D 4D
City Limit - Teesley "A .... A" "A" "A" "A .... A" "B .... C/D .... D/E"
FM 2499: ........ 4D 4D 4D 4D
IH 35 - FM 2181 "A" "A .... A .... A"
Hickory Creek: ...... 4U 4U 4U 4U 4U 4U
Teasley - FM 2499 "A" "A .... A" "A .... A .... A"
State School Connector: .... 2U 2U 2U 2U 2U 2U 4U
Ranchman - State School "A .... A .... A .... A .... A .... C/D .... A"
24,450
4D/6D
17,550
4D/4D
19,200
4D/4D
HOBSON
2U/4U
22,250
4D/6D
24,050
7,150
4U/4U
RYAN
"'~O~....~CREEK
18,200
16,600
2U/4D
22,300
2U/6D
2U/4D,~L
YEAR 2012 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
7,250
-/2u
13,500
2U/4D
2,000
9,400
2U/4U
I'
20,950
0
0
'-r
000
-/4D
ROBINSON
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
--EXISTING STREET SECTION
TEASLEY (FM2181)
FIGURE A-1
~:, 0 5 ~!"
26,450
~o( 04~
J
19,300
40/40.
HOBSON ~
15,200'~m'
2U/4U
24,950
40/6D
27,550
RYAN
20,950
2U/4D~
19',1 O0
2U/40
26,100
2U/60
YEAR 2014 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
21,450
40/50
8,950
4U/4U
9,250
-/2U
15,650
2U/40
4,500
24,150
2U/60
9,400
2U/4U
5OO
-/40
ROBINSON
LEGEND
24-HR. VOLUME
· NEEDED STREET SECTION
--EXISTING STREET SECTION
TEASLEY (FM2181)
FIGURE A-2
28,450
21,350
4D/6D
25,800
4D/5D
HOBSON ~
16,700~r
2u/4u
27,700
4D/6D
51,100
10,700
4U/4U
25,700
RYAN 2U/6Di
29,900
21,650 ' 2U/6D
2U/4D
YEAR 2016 PROJECTIONS
TEASLEY LANE CORRIDOR STUDY
DENTON, TEXAS
11,250
-/4u
7,000
27,550
17,800
2U/4D
9,400
2U/4U
I'
J
000
-/4D
ROBINSON
LEGEND
24-HR. VOLUME
NEEDED STREET SECTION
EXISTING STREET SECTION
TEASLEY (FM2181)
FIGURE A-5
TEASLEY LANE CORRIDOR
CAPITAL IMPROVEMENTS SCHEDULE
The following schedule ~rovided a year by year listing of roadway improvements to be implemented
based upon the April 11 , 2000 Teasley Lane Corridor Traffic Study assumptions. A strategy for
funding, design, and construction has not yet been developed. The May 23fa, 2000 Council work
session has been tentatively scheduled for further discussion regarding the implementation strategy.
YEAR 2000
YEAR 2002
YEAR 2004
HICKORY CREEK ROAD - City Limit to Teasley
STATE SCHOOL CONNECTOR - Ranchman to State School
[2U to 4D]
[ -- to 2U]
YEAR 2006
TEASLEY LANE - Lillian Miller to Robinson
TEASELY LANE - Robinson to Hickory Creek
TEASLEY LANE - Hickory Creek to City Limit
[2U to 6D]
[2U to 6D]
[2U to 6D]
RYAN ROAD - Country Club to Teasley
[2U to 4D]
YEAR 2008
TEASLEY LANE - 1-35E to Londonderry
HOBSON LANE - Country Club to Teasley
[4D to 6D]
[2U to 4U]
YEAR 2010
ROBINSON ROAD - Teasley to Harvard
FM 2499 - I35-E to FM 2181 (Teasley)
[2U to 4D]
[ -- to 4D]
YEAR 2012
TEASLEY LANE - Hobson to Lillian Miller
[4D TO 6D]
YEAR 2014
LILLIAN MILLER PKWY - 1-35E to Teasley
[4D to 5D: additional northbound lane]
YEAR 2016
TEASLEY LANE - Londonderry to Hobson
RYAN ROAD - Country Club to Teasley
STATE SCHOOL CONNECTOR- Ranchman to State School
[4D to 6D]
[4D to 6D]
[2U to 4U]