2018-066 Retired SubstationsDate: May 25, 2018 Report No. 2018-066
pg. 1
INFORMAL STAFF REPORT
TO MAYOR AND CITY COUNCIL
SUBJECT:
Recently, a City Councilmember requested an update regarding old electric substation properties,
their status, and potential uses.
BACKGROUND:
An April 28, 2017 Informal Staff Report (ISR) addressed a similar question. The 2017 ISR
remains valid except for the estimated timeframes:
The old Hickory Substation must remain energized and is used to serve residential
customers in the Historic District, commercial customers, Texas Health Hospital, and the
northern half of the UNT campus. It cannot be remove from service for at least another
four to five years until the new Hickory SF6 Gas Insulated (GIS) Substation has been
constructed, tested and commissioned.
North Lakes Substation would be on the same timeframe as Hickory Substation, in
another four to five years, due to the need to keep in service a 69kV to 138kV
Autotransformer that is necessary for reliable and safe interface between the two different
transmission voltage levels.
The old Arco Substation site is owned by Texas Municipal Electric (TMPA) and the old
substation site is surrounded by Oncor and Atmos Gas facilities. The site is heavily
encumbered with above ground utility equipment and utility easements that are being
used. TMPA has informally deliberated, possibly considered selling their portion of the
land that the City of Denton or other franchised utilities may have an interest in a future
procurement.
Currently (as of mid-May 2018) Kings Row Substation is the only substation that is
actually out of service. All of the above ground de-energized equipment remains on site.
Some of the equipment parts have been used to help supplement repairs of the sister
Hickory substation. The old Kings Row and Hickory Substations are considered sister
substations since they both utilize similar 1960’s vintage equipment. The old substation
site remains one of staging sites on the northeast side of Denton for materials and
equipment for the capital improvement program which will continue for the next few
years. There are a few options for King’s Row and some factors that will affect the
availability of the site:
– The old Kings Row substation site is located in the Northeast portion of Denton,
the location has been strategically located for staging of electrical materials and
equipment related to CIP projects. The DN to AR transmission line construction
just concluded this month; therefore, the staging area use need related to
substation and transmission CIP projects is diminishing. However, it should be
Date: May 25, 2018 Report No. 2018-066
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noted that the strategic location of the site could also lend itself for consideration
as a possible long term staging or storage area for distribution line items such as
fuses, wooden cross arms, insulators, lightning arrestors, etc., that would aid in
improving or speeding up outage restoration times in this area of Denton. This
nice heavily treed area in Denton has been identified on a heat map that was
shown at a recent Council meeting, as an area that has historically experienced its
fair share of outages caused by squirrels. Having typically used distribution
materials staged in this strategic area where most needed, could be a positive
benefit for the adjacent neighborhoods
– The site could be cleared by a contractor after it is bid out. It then must be
remediated environmentally by another contractor after bidding. In order to make
it available for a possible public repurposed use it would be 18-24 months at a
cost of approximately $2M.
– Another option available would be to have DME use its labor resources to retire
the equipment other than the transformers. This has potential for reducing the
cost. The environmental remediation and site restoration work would still have to
be accomplished after DME has removed equipment from the site. For it to be
available for repurposing in a 3 to 5 year timeframe, the overall cost might be
reduced as much as half, especially if the work could be sequenced with work in
other stations.
– With the potential environmental (hydrocarbons) and unknown bidding factors, it
is difficult to be more definitive on both cost and time. Work would most likely
be disruptive to the neighbors with cranes, large trucks and equipment required
over a 6 to 9 month very active timeframe.
– The intended end use and any drainage requirements could also have an impact on
the cost.
– One other item needs mention. The above costs are predicated on the existing
precast concrete fence remaining in place. Changes to or replacement of the fence
would add cost.
The old Locust Substation site is presently serving a large majority of the downtown
customers, including a significant portion of the residential, commercial, and industrial
customers in the area such as Acme Brick. Once the transmission line segments on both
sides of Locust Substation are fully converted to 138kV and all of the customers have
been moved over to the new Locust site, then the old Locust substation site can be de-
energized. It should be noted that a major fiber optic hub is being utilized in the brick
building at the old Locust Substation site.
DISCUSSION:
As described on the second and third pages of the previous 2017 ISR, multiple steps are
necessary to retire an old unused substation site and to consider possible repurposed uses. The
removal of equipment will likely be the least expensive part of the station retirements. It is
Date: May 25, 2018 Report No. 2018-066
pg. 3
possible that DME’s substation field personnel can undertake the retirement of the equipment in
substations once the ongoing new CIP project work nears completion. Doing it sooner will
likely require going out to solicit contractors that specialize in removing old substations in or
near energized high voltage environments to ensure that it does not negatively impact the
reliability to the citizens in Denton and that it can be performed in the most safe manner possible.
CONCLUSION:
In conclusion, the primary focus to date has been on safely and reliably constructing projects that
benefit the citizens of Denton while solving electric system transmission and distribution (T&D)
deficiencies and contingencies that have been identified. Staff will keep the Public Utilities
Board and City Council updated as timing and opportunities arise to shift resources necessary to
fully decommission the old sites and equipment.
ATTACHMENT(S):
1. ISR 2017-026 Retired Substations
STAFF CONTACT:
Brent Heath
Executive Manager of Energy Delivery
(940) 349-7180
Brent.Heath@cityofdenton.com
Date: April 28, 2017
INFORMAL STAFF REPORT
TO MAYOR AND CITY COUNCIL
CTTR_1F,C'T
Report No. 2017-026
Council Member Briggs requested information on a process to review potential land use options for
retired electric substation sites.
BACKGROUND:
At the March 21, 2017 Council meeting, Council Member Briggs requested a work session on
determining a process to review old substation sites and possible land use options. DME's Capital
Improvement Program has several projects to construct new substations or reconstruct existing
substations during the transmission system upgrade from 69kV to 138kV, which began in 2011 and
will continue through 2022.
DISCUSSION:
There are a few potential substation sites where land reuse could occur in the future due to the new
construction or reconstruction. Most of these sites are in various stages of the design and construction
process, and old sites that have recently been de -energized are still needed operationally and logistically
for the staging of equipment and/or back-up operations until the transmission system upgrade project
progresses closer to completion. This memo will provide a brief description of potential sites where
land may be available for reuse and discuss general steps and guidelines for a process.
Potential Sites
There are two substation sites that will be newly constructed at a separate location and their respective
old substation sites may no longer be necessary to DME. The first site is Kings Row substation
Attachment 1). The new Kings Row substation (at the corner of Kings Row and Loop 288) is fully
operational and the old site to the west on Kings Row Street was de -energized in late 2016. Although
the old site has recently become inactive, a few steps need to take place before it is fully
decommissioned, no longer useful, and can be considered for other uses. The old site is an important
staging site for materials and equipment for the conversion of the entire transmission system to 138kV,
until at least 2-3 years out when the project progresses closer to completion.
The second new construction substation where the old site may no longer be necessary is the Hickory
substation (Attachment 2). The new Hickory substation was selected to be constructed on a site directly
across the street from the existing Hickory substation, across Bonnie Brae Street to the East. This
project is in the GIS substation and UG Transmission design phase and the new Hickory Substation
will not be online and operational until 2020.
In addition to those two new construction sites, there are a few substation sites being reconstructed,
which could open partial land segments for repurposing or other landscaping or beautification efforts.
However, the exact site design and configuration may not be known until the sites are through the entire
process with a plat, design, environmental assessment, land acquisition, permit, and construction.
Variables through this process may influence if, and how much land, is available or no longer useful.
The following are the potential reconstruction substation sites where partial land may be available:
Locust, North Lakes, Arco, Industrial, and Jim Christal (Attachment 3).
pg. 1
Date: April 28, 2017 Report No. 2017-026
Steps to Retire a Site and Potential Process for Reuse
Although these old substation sites may become inactive, they may be necessary in the interim to serve
as a staging area for the system upgrade project, to provide back-up if required, or may contain other
equipment owned and operated by TMPA where removal and proper asset retirement must be
coordinated. The below description generally outlines a process to decommission a substation site once
it is no longer required for electric operations and how the property could be considered for other uses.
1. Sale, Disposal, and Removal of Assets — DME will work with the City's Accounting and
Purchasing Department to properly and legally retire and dispose of the older assets that are no
longer required nor useful to the City. All of the large and heavy equipment such as Power
Transformers, Switchgear, Control Building, and Structural Steel remain on site after a
substation is de -energized. Very large and heavy items such as the Power Transformers and
Control Buildings are not easily moved, and will go through either an RFP process or Auction
process for disposal and removal from this site by the awarded party.
2. Environmental Assessment — When the City purchases or sells property, an environmental
assessment must be performed by an independent professional, and staff recommends the same
process be undertaken if these sites are to be used for other purposes. Generally, there are two
phases to an environmental assessment. The first phase is a preliminary assessment by a
qualified individual to analyze historical land use of the property, current use, assessment of
what is on the property or around the property, and a number of other factors to make a
determination if there is a Recognized Environmental Condition ("REC") indicating the
possibility of contamination. If a REC determination is made, there is a second phase to perform
sampling and testing. This sampling and testing depends on the RECs, but often includes soil
and shallow ground water testing. Samples are sent to a lab to test for contaminants, and the
results are compared to either residential or commercial standards depending on the anticipated
future land uses. If contaminants are found, a plan is developed to remediate the site to
acceptable standards.
3. Potential Uses — Concurrent with the first two steps, staff can perform an analysis of each site
looking at its past uses, location, size, configuration, public access, public safety considerations,
adjacent and neighboring properties, nearby amenities, and so forth, and provide options for
consideration depending upon the features of each site. Generally, staff believes a site could (1)
become a public space (such as a park, open space, landscaped area, community garden, or tree
stand), (2) be maintained by the City for other operational purposes, or (3) be offered for sale
adjacent land owners may have interest). Because of the differences between each site,
potential uses could vary; however, most of the sites are small and are more likely to be
compatible for an open space, landscaped area, community garden, or tree stand. The analysis
and options could be used to then facilitate potential site repurposing discussions and gathering
of citizen and neighborhood input and ideas.
4. Citizen and Neighborhood Involvement — After assets are removed and an environmental
assessment and remediation (if needed) is completed, staff could facilitate site repurposing
discussions for potential uses led by the Community Affairs Division and DME. A similar
method to DME's use of public input received through the electric site and route selection
processes for the CIP program could be used to gather citizen ideas, through citizen mailings,
IVR phone calls, and formally scheduled public Open Houses for each of the surrounding
Mai
Date: April 28, 2017 Report No. 2017-026
neighborhoods. All citizen input and recommendations could be collected through electronic
surveys that would be filled out at each public open house and for several weeks subsequent to
each public open house meetings. The citizen survey data could be analyzed to help provide
both the Public Utilities Board and the City Council possible ideas and recommendations based
upon the most favorable citizen ideas and input. Any options presented would include public
input received, actions and funding required (both one-time and ongoing), and review of land
use compatibility and zoning regulations.
CONCLUSION:
DME has primarily focused its resources on safely and reliably completing all of the approved projects
included in the substation and transmission line upgrade program, but plans to shift resources as the
program progresses to fully decommission the old sites and equipment. Staff respectfully requests to
come back to Council within the next 18-24 months to provide an update on DME's CIP program with
a status on each of these potential sites and a proposed process including a timeline and resources to
review property that will be no longer useful nor necessary for electric operations.
ATTACHMENTS:
1. Map of Kings Row substation
2. Map of Hickory substation
3. Map of various reconstruction substations
STAFF CONTACT:
Phil Williams
General Manager
Denton Municipal Electric
Rhil.williams cTcityofdenton.com
940) 349-8356
Sarah Kuechler
Assistant to the City Manager
sarah.kuechler&cityofdenton.com
940) 349-8356
pg. 3