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HomeMy WebLinkAbout06-1978 tprru:rct f Douche Ross (30. k k June 12, 1978 s r 1 H Mr. Chris Hartung i FCity Manager \ City of Denton 515 L. Moginney Street Denton, Texas 76201 ~ Dear Mr. Hartungs I Enclosed is our ,report on the Water/Wastewater Cost of s Service and Rate Design, esign _study, Our report discusses both the r} recommended rates for water and wastewater services and the meth- odology`we used in developing these rates, We recommend these rates be adopted as soon as possible by ' the City Council, Xf you have any questions regarding this report, please con- tact Sam Rhodes or Jack Stowe at 214/'141-3353. Very truly yours, 04 ~J Y, red f ~ J , 1 2001 BRYAN TOWER • SUITE 2400. OALLAS, TEXAS 78201 • (214) t41.3663 • M1 t Ndd7+R'I {FYl CITY OF DENTON WATER /WASTEWATER COST OF SERVICE AND RATE DESIGN STUDY r j TABLE OF CONTENTS I • .INTRODUCn-ION p-aqe l.f REVENUE REQUIREMENTS Y CUSTOMER GROWTH AND USAGE PROJECn+iO 2 ' i NS j f j IV. TREATED WATER COST OF 4 s8xvxc,~ V. TREATED WATER 5 E i IRATE DESIGN I VI, WASTE'WATE'R COST OF 6 SE it f RVICE AND RATE DESIGN f. VII. ACCOUNTING SYSTEM F3 1 VIII. - RECOMMENDATIONS ,I SCHEDULES 1 THROUGH 15 13 ! Appendix Ordinances zllustrative Industrial wastewater iul Appendix $ ~ Customer Discussion Monitoring plan GOAeral 1 Y 1 ,l . ~a 41 '~laf t, A::q }1t ~ r~~~r~.rF,ca . INTRODUCTT0 i TOUche Ross & Co. was engaged by the City of Denton in April 1978 to conduit a cost of service and rate design study for the t water/wastewater utility system. t1' The accompanying forecasted statements of revenues and s expenses and capital expenditures were supplied to us by City personnel to assist in the determination of the revenue require- ments for the periods of dune 1978 through September 1979. Estimated revenues beyond the 1980 fiscal year were not included because the City's contract with Dallas for the purchase of raw water will expire in 1980. The forecast operating statements supplied to us by City personnel are intended to serve as a reasonable guide for estab- lishing rates which permit the Denton wator/wastewater utility system to collect sufficient revenues to cover operating expanses, debt service, and provide funds for construction and general fund transfers as determined to be appropriate by City Officials. Any financial projections supplied to us by City personnel and usod in E our report to develop rates should not be relied 'upon by any outside 'k party for the purpose of evaluation for loans or investmon,ts. FurtherrAoxe, since forecasts are based on assumptions about circttm- i) stances and events that have not taken place, they are subject to variations that may arise as future operations actually occur. ( Because these assumptions .end rationale are dependent, in large i part, on the realization of these estimates, we are unable to and do S' not express an opininn as to the reasonableness of the forecast nor ~X of the underlying assumptions and rationale. Accordingly we cannot give assurance that the forecasted results will actually be attained. Li the following seotiona of this report discuss both the 4`! recommended rates for water and wastewater services and the i methodology used in developing these rates.- In addition, we have i included an illustrative Industrial Wastewater Ordinance in p~ appendix A as well as a discussion of a Customer Monitoring Plan in Appendix N. h~ i 1 i. ' ~t~ tI +1 Al 177 t C ~ ~~lCf ~fl N[zcs ~1l.Li III REVENUE REQUIREMENTS The development of the estimated revenue requirements for the City of Denton's Water and Sewer System for the fiscal year ending September 300 1978, was based upon the current budget as revised by City staff for known changes. In addition, a capital P outlay operating fund was established by agreement between the Public Utility Board and the Steering Committee to aid in the financing of the Capital Improvement Program, The overall revenue requirements include a return on system equity which will permit a six percent transfer to the General Fund, and earnings sufficient to maintain the financial integrity of the Water and Sewer 9yetem, Schedule 1 details the total revenue requirements for the current fiscal year which are estimated to be '),733,3194 To develop projected revenue requirements it is necessary to consider the requirements of the Capital Improvement program to determine future financing requirements. Schedule 2 details the j current Capital Improvement Program of the City showing estimated total expenditures of $70].73, 703 ..over thv next four years which represents a 63.94 inorease over the Water/Sewer estimated net i investment its of September 30, 1978. In discussions with city officials, it was determined that to accomplish the capital 1 Improvement Program on a timely basis it will be necessary to issue new bond financing in early 1974, 1980, 1981, and 19$2, The early ' r;. 1979 issue is eatimt~ted to be approximately $2 000,000 which will in primarily be dedioat;ed to the Step III requirements under the Environmental Protection Agency PL-92-500 grant funding for the expansion of current wastewater treatment facilities, The city of Denton is currently entering Step III (contructi.on phase) of the cwt project which has an estimated total cost of $8,325,000 an of i` May llr 1978, of which $6,291,000 is available under grant funding . The 1979 bond issue is necessary to avoid jeopardizing the City1s participation in the grant funding program. It is estimated that an additional $11500,000 bond issue will be regoired in early 1980 and $1,000,000 bond issues each for 1981 and 1982, , i, projeated revenue requirements for the fiscal years 19"9 and 1980 assume bond issues of, $20000,000 and $1,500,000, respe,i.ively) r' at six and ono -quarter (64%) interest having a_ twenty-fi~a year maturity. in addition, at the direotion of the Steering Committee and Public Utility Board, operation and maintenance expenses have been increased 108 per annum to reflect the estimated impacts of s (N inflation and system growth, As shown on Schedule '3 estimated ! revenue requirementsfor the fiscal years 1979 anc 1980 are $4x050,23,5 and $4,438,953, respectively. i Schedule 4 details estimated revenues for the fiscal year at both current rates and recommended rates assuming implementation of. recommended rates in June 1978, Ad this schedule demonstrates, the estimated maximum year debt eoVerage under currant rates would be inadequate for a 1979 bond issue of $2,000,000 which iA required to maintain participation in the IPA grants program, Current Bond j Covenants require maximum year debt coverage of 1,3 times debt a 2 di ,g 7otuftel?ass~~Cia servioe including the proposed financing before the issuance of additional debt. Additionally, at current rates it is estimated that sufficient funds will not be available for transfer to the General Fund at the desired 68 level. € rv This analysis reveals that historical rate relief has partially improved the earnings capacity of the Water and Sewer Systom, However, such relief has been and will continue to he inadequate to meet the inflationary trend of operating and mainte- "i nance expenseer future financing requirements, and to provide sufficient earnings for the appropriate transfer to the General tip Fund and maintain the financial integrity of the System. Estimated revenues generated under the recommended rates will produce adequate maximum year debt coverage of 1.59 times for fiscal. year 1978, will allow an estimated transfer to the General 3 Fund of $180,404, and will generate an additional $161,000 to be l restricted for the future capital improvement program as shown on Schedule 5, Schedules 4 and 5 also show projected figures for the E t°~ fiscal year 1979, The revenue forecast under recommended rates is based on the assumption that rate relief will be granted for the month of June 19789 Postponement of rate relief implementation may have a pi serious detrimental impact on the System's financial position and ; { may result in the City's inability to issue the required new i i financing. Estimated revenues beyond fiscal year 1979 were not included l G because the City's current contract with Dallas for the purcliase of raw water will expire duri.ng'1980, Currently the City is studying several alternative sources of raw water supply. At this time the City is unable to determine the extent of the potential impact on the cast of water, We recommend that the City begin negotiations { with the City of Dallas as soon as possible to obtain an extension EI~ of the current contract or the initiation of a new long-term cony traot depending upon the immediate and long-term goals of the City, t y9N!}IX9 i~ 1 lF~A6.f ya.5l"N::91 J , kJlIC~aL'~11.~c~(ll ~ III. CUSTOMER GROWTH AND USAGE PROJECTIONS i ` our analysis of customer growth for the Residential and Commercial/Industrial class of customers was based upon the preced- t ing five-year period from March 1973 to k"ebruary 1978. The average percentage increase in customers for the Residential class for this period was 2.18 With an average growth for the last two years of 3,18 To plan for future growth in water/wastewater customers, s consideration must be given to the growth in population which is expected to occur in the City of Denton. In addition, the use of historical growth patterns for forecast purpones which contain j abnormalities, such as the recessionary effeat6 on growth experi anoed during 1973 through 1975, must he adjusted to reflect estimated normal growth patterns. Our discussions with city per- sonnel and the Steering Committee resulted in an overall estimated growth rate of 3,18 to be used in the estimate of all future custo- mer it. is important to note that the projected growth factor of 3.1.8 is in line with the population growth forecasts of 3.48 developed by the North Central. Texas Council of Governments r? for the City of Denton, Projeoted water usage for the Residential and' Commer- 1 r alai/industrial customer classes was based 'upon the preceding four years, consumption to average the effects of weather and price j elasticity. The Sales for Resale class was assumed to increase consump- tionby 158 for the purposes of our study. Discussions with City j personnel and the Steering Committee indicated that 158 would be a reasonable estimate of the increase in water usage for this class. Water consumption for utility operations and city accounts r was held at the level experienced over the last twelve-month period k k~ due to lack of substantive information concerning any possible growth for these olasses. Raw water use by the electric steam plant r was based upon estimates provided by Electric Department personnel. Your Re ioNorth Central Texas Council of Governments, Vol, 121`tMo; 4 April 1978, 4, air.. 4e;r+.r1 A vtt:f5i 7 4Y.1V1'tvy s ~ ~dllC~iE ~SS£>~ it IV,~C08T oz.SECE _ TREATF;D WATER i To design water rates c:Lassl s which are refl Yectimusvetbe of each customer I identify t Use Of he costs associated with a stud conducted to i i with each customer class, The City of Denton currently maintains its records such that Dix separate customer classes could be utilized for the the cost of service study, These customer classifications are follows: purpose of as Residential Commercial/xndustrlal Sales for Resale (r; City accounts j Utility operaLions Raw water sales to the electric steam plant i Ii From the City's records, historical information concerning the number customers and the monthly ao was gathered d customer gsumption in each class class, and analyzed for use in allocating cost to each t, The allooation methodology employed by +rauahe oss 4 Co, for. this cast of service study was the Rage, xaegs,`anA Customer related allocation factors. water oast of service studies handmis ethodol6gyExoess, and customer Water Works Association. I-1 Baas costs are costs amoun which tend to vary dlrentl it w of water consumed plus Operating and capital c()stsiwassoaie ated its average water of purohas oonsumption, Base costs include llhe costs 1) water, chemical costs ' Capital oast of water facilities assoeiated4Wi power, 'and average consumption of each customer class, er, and the E the Excess capacity costs are costs essoa snd iated with mooting I requirements in excess of average consumption and inglude capital + operating expenses For additional plant a~ beyond that required for and. system capacity usage E01, the City of Denton is measuredponlyofor the total a etem,~ } To develop the peak usagd'by customer class, the peak system day was allocated to each class based upon the peak month usage by customer class for which metered ineormation was available Customer costs are those costs associated with serving; Customets regardless of the amount of water used, Customer costs include motor reading, billing, customer accounting and Collection ~1 expenseu, maintenance of meters and services, and the Capital costs r associated with meters and services, Schedule 6 shows the results 'of the cast of service utud by customer class for the fiscal year ending Septomber 34, 1978. L fir,;, t `btfC~tC~JdS~~'Q V. RATE DESIGN - TREATED WATER rr j Once the cost of service study has been aompl~3tad and each assi ned tal step isrtoldesign8abrate which willpreortion Of cover these co stasand w~bO hicheis in accordance with the City's goals and objectives. The rate schedule currently in effect in the City of Denton for the Residential class of customers is as follows: Block Rare 0 - 2,04 gallons, including $ 3.25 per month customer charge , MEAL } next 18,000 gallons 65 per ,55 per MGAL next 30,000 gallons 50 per MGAL 'Y above 50,000 gallons , our analysis of the usage characteristics for the Residen- tial class indicated the following characteristics. { Average monthly water usage of approximately 14,000 gallons - 67..58 of all Residential customers use 100000 gallons or less 61,56 of all Residential water consumption would be billed at or below 10,000 gallons 98.6% of all Residential customers use 54,000 gallons or less 90% of all Residential water consumption would be billed at or below 50,000 gallons We recommend that the current block structures be modified to reflect these characteristics. The results of our recommendations are shown below: B1oak Customer charge $ 2110 per month ] 0 - 10 000 gallons 090 per MtlAL I 000 _ 5ot006 ggallons $75 per MOAL le 501000 gAllons ,70 per MOAL i in determining the level of rates to be oollenti h~rU each withkrrevenuefystabil ty, consideration Thisa wasivagreed upo idin byg the Steering t be th 1 Committee to thes1 vet of rate a for eaTouo ch black Wepursue it) the development of f hhis by designaoste iate bh Resid n 1aLh laesa hnd lmlt the _I of the fixed in- would then recover coat O d main base operating study, The othert twott devoe coats eloped service ing ..fixed coots plus the excess. operating and maintenance cost... ~.i assigned to the Residential class in the coat of service study. • ~rt•,5 taewa 1 it •ntY_+~ JOlu'I t2RDtSS f1CU I We recommend that a separate eustom.ar charge be instituted for the Residential class which will reoovor the customer related cost incurred by the water utility regardless of the amount of water used. j The rate schedule currently in effect in the City of Denton j for the Commerical/Industrial class of customers is as followst F! Block Rate 0 - 2,000 gallons, including oustomor charge $ 5,00 per month i1 next 18,000 gallons .65 per MaAL next 300000 gallons 455 per MaAL r above 50,000 gallons .50 per MEAL As can be seen, the only difference between the current Residential rate and the Commercial/Industrial rate is the rate in ! the first block. our analysis of the Commerical/Industrial usage ` characteristics indicated the following eharacteristiost - 82.48 of all water consumption was above 100,000 gallons 168 of all Commercial/Industrial customers used 100,000 gallons or above 1 Ke feel that this is too 'great of a range for one class and recom- mend that in the future, the City consider dividing this class into subclasses such as Commercial, Industrial, and Univerdivies, At this tinie, due to the disparity of consumption within this class, we reoomtnend that the City set a customer charge at $5,00 for the Commercial/Industrial class with a flat charge of $0.68 MCAL for all water oonsumption, k 1 I} In order to recover the cost associated with serving the ! i Sales for Resale olass, we recommend a customer charge of $93.00 to ! recover the fixed cost for billing!, meter reading, eto,- In ' addition to this, a flat charge per MdAL of $0,61 should be charged } to recover the remaining costs incurred in serving this class, l A summary of the recommended rates for the above classes and the remaining classes of Utility operations, City aocountsp and )Raw water sales to the electric steam plant are shown on Schedule 7. The rate design for those classes was established on a `basis consistent with the cost of service for these classes, As shown on Sabodule 71 the City aocounts and Utility operations will have a charge of $.90 per MCAL and a customer charge of $6.95 and $3.35 par month, respectively, to recover the customer related ibsts assooi- ated with these glasses. The charge of $.12 MOAL foi Raw water to the electric steam plant is designed to recoup the operating and capital cost of r~ providing raw water to the eleatric Steam plant. } 44L' schedules 8 and 9 show a comparison of the current rates to the prop6804 rates at various levels of water consumption and the dollar increases at each level for the Residential and Commer- trial/Industrial classes of oustomers. ` IOflCJlPR[u'SE~CL! ,t i VI, WASTEWATER COST OF SERVICE AND RATE DESIGN WASTEWATER COST OF SERVICE Sewage treatment demand reflects both the volume and pollu- tant levels of raw sewage to be treated. Volume is expressed in j millions of gallons per day (mgd) or millions of gallons per yybar (mg/year), pollutant levels are expressed in milligrams per .1 tor (mg/1) of Biochemical Oxygen Demand (BOD) and Suspended Solids x~ (SS) Sewage treatment demand estimates are necessary input for the determination of operational expenses and billing volumes for a sewer utility. r The majority of sewer system expenses are directly related to the volume or pollutant levels oil the sewage. Therefore, estimates of sewage treatment demand are essential for an accurate ;j letermination of future ;plant expansion and for proper allocation of the costs of sewage treatment to various user groups, sewage Volumes "J t The approach used to estimate sewage treatment volume by ' I r customer class was as follows Residential - estimated wager consumption times a return flow factor of 90t for the nonirrigbtiohal months of October I + through April. The irrigational months of May through September are held constant using the second highest non- irrigational month's consumption, !•1 Commeroial/Industrial - estimated water consumption times a return flow factor of 80% for each month. j i~aa Outside Service Fees - metered volume. G 'f City Accounts - same as Residential, ` The return flow factors were selected so as to recognize that 100% of water usage in any given month is not returned for treatment and is based upon past studies of cities with similar ((t, austomex characteristics, Additionally, holding the second highest nonirrigational month constant for the Residential class during the irrigational months will not burden the sewer customers with the extra summer water volumes that are not returned for treatment, such as lawn irrigation, This differential was not applied to the Industrial customers ainoe analysis of the olaosest water donsump- tion indicates a fairly stable amount of water usago throughout the Year r; Sewage Pollutant Levels The average pollutant loading for the treatment plant was developed from data submitted by the city and the "City of Denton, Texan, Sewage System Improvement Facility plan" submitted to the [ ].del'"slp$p~; IinicheRoss &Cu Environmental Protection Agency for procurement of pI,-82_500 funding. Average customer class loading was developed by assuming an average loading for the Residential class of 240 mg/1 of SOD and SS and weighting the total average system loading for customer class volume to arrive at an average loading for the Commer- cial/Industrial class oe 260 mg/l of BOD and SS, Sewer _Syst oft oP 9eryioe The sanitary sewer system cost of service for the City is comprised of the following areas Collection System expenses ' - Sewage Treatment expenses -Debt service expenses - Capital outlay Fund - Return on System equity - Customer Service expenses f The estimated 1977/1978 total revenue requirements for the sewer System is detailed on Schedule 1. ~.i WASTEWATER RATE DESYGN The basis of the sewer rate design ; is consistent with the three major objectives of theisewers report of the study$ 1) Compliance with federal user charge guidelinesn 2) a financially self-supporting sewer system, 3) sufficient net system revenues to transfer 68 of system equity to the General Fund. This section details the development of the sewer user charges and industrial surcharge. 1.,. Unit cost Deyeloument r, The proper design of an equitable sewer user charge and i industrial surcharge requires an allocation of all operational expenses between the three units of sewage treatment demand - BOD, sa, and volume - to derive a unit cost of sewage s ' unit costs are then used to develop sewer rates and asVaccomponent for use in the surcharge formula. Allocation of Cost of Service l ! The expense items applicable to the sewer system are al,lo- sated as shown on Schedule 10 to the three major functions of { sewage treatment demand BOD, 89, and volume. ' r.., SOD expenses are determined by costs associated with the reduction of the Bioohemieal oxygen Demand of the sewagel SS expenses' likewise are determined by oosta associated with the ) removal of Suspended Solids from the sewage, Generally, SOD and Ss expenses are associated with the costs of the treatment plant t operations, ~:I 9 t 7inu1tel?ass~Cr~ Volume expenses are those expenses associated with the f t P collection of sewage and its physical movement with no assumed P reduction in the level of pollutants, Therefore, all expenses associated with the City of Denton's collection system and sewer operations are allocable to volume, Unit Cost `actors cost factors are developed for units of treatment demand on the allooatad expenses shown on Schedule 10. The units of treat- ment demand are based on the average system pollutant levels of BOD and SS (which are assumed to be cunstant over the study period) and E the estimated billed volumes for the test year. The allocated expense is then divided by the total estimated units of treatment r to derive a cost per unit of BOD and 5S, User Charges and Industrial Surcharge Design f Volumetric user charges are derived from customer classes of ; ff Residential and Commeraial/Industrial from the unit costs for HOD, Bs, and volume for the test year based on the average pollutant levels for the different type of customer. These volumetric user t charges plus the customer service cost are then used in determining the minimum bill user charge and are used as factors within the industrial surcharge formula. The system of user charges and industrial snroharges is designed to be computed on the basis of metered water sales, For domestic customers the user,oharge is designed to be computed on i•,I the basis of 988 of water oonsumpt.ion for October through May and the second highest month during this period remaining constant for 1 Appril through September, Billings for customers with no congump- i. tion history will be estimated at 60% of actual, water consumption for the irrigational months. Residential customers whose usage is less (luring the months of April through September than their second highest month during the period October through May shall be billed (4, at 98~ of their actual water consumption. The charge and surcharge are designed to be computed on the basis of monthly metered water sales times a return flow factor of 808, Schedule 11 shows the user charge computations for the Residential and'Commercial/Industrial classes of sewer customers, ; Volumetric user charges are computed for the tbgt year during the i study period bated on assumed pollutant levels for each class of f customer, For Residentiala, city accounts, and outside service foes, 240 mg/1 of DOD and 240 mg/l of SS ate usedt 260 mg/l of'BOD and 260 mg/1 of SS e,,e used for Commercial/Industrial. The cost for the removal of each unit of treatment demand of BOD and SS is multiplied by the assumed level of HOD and $So Adding the three costs Bon, 8S, and volume - yielda the volumetric user charge per 11000 gallons of estimated return flow for each customer, } class. a 10 t" ti;~ j IottCltCf~uss£~Cu , Sewer Rates Schedule 12 presents the recommended sewer rates to be implemented in the City of Denton. The recommended rates have been designed using the test year user charges developed on Schedule 11 and, the estimated test year customer related expenses shown on Schedule 10. j( In addition, the recommended rates are designed to recover the estimated revenue requirements for the fiscal year ending Septem- ber 30, 1979. sjj The minimum charge for domestic users is based on a minimum volume of 21000 gallons per month plus a customer service cost. A i►" volumetric rate per 1,000 gallons is applicable to return flow greater than the minimum return flow of 21000 gallons. The Commercial/Industrial customer's minimum bill is based on an estimated return flow of 41000 gallons plug a customer ser- vice cost. All return"flow volume over the minimum should be com- puted at the recommended volumetric rate. Industrial Surcharge w~ Shown on Schedule 13 is the industrial surcharge and cost (~J factors for the teat year. The objective of an industrial sur- charge for, sewer service is to' permit the collection Of a,surcha'rge i when a user discharges sewage of greater BOn and SS content than the I. average content on which the user charge is based* in the case of the City of Denton, the average pollutant content is 260 mg/1 of BOD j and 260 mg/1 of SS. Any industrial' customer that contributes sewage that exceeds these levels pays the same base 'rate as all l other industrial ouetomers, plus a surcharge based on HOD and/or 95 content greater than 260 mg/l. l This recommended surcharge is applicable to Industrial. w customers only as defined by the Environmental Protection Agency (EPA). An Industrial user is defined in cor.R. 9 35.905-8 as anyy nongovernmental user of publicly-owned treatment works identified in the following divisions of the 'standard industrial Classifi- cation Manual (81C), 19721 t !'l j Divisions Description A Agriculture, Porestry,_and Fishing B Mining LJ D Manufacturing R Transportation, Communications, Eiectria, Gas, and sanitary services 1 i services The City currently does not maintain an industrial customer class file on Industrial customers by SIC classification. During the course of this study, each Commercial/induetriai customer as of March 1978 was assigned the appropriate SIC code, it is recom- mended that the City group the Commeroial/Industrial customers by SIC coded those customers whose SIC codes fall within the defini Lion of the EPA of an industrial uoer should be consolidated into an J` industrial customer class. 11 6'st)C U I r~OtlUtf?~USSt~~ I Those customers remaining whose codes do not identify them yi as industrial users will he consolidated to farm the Commercial class. Additionally, each new non-Residential, customer: applying for service should be properly identified by the appropriate SIC code in order to accumulate the appropriate data. After the proper identification of Industrial customers the City may initiate the industrial surcharge, rE Schedules 14 and 15 'show a comparison of the current rates to the proposed rates at various levels of water consumption and the dollar increases at each level for the Residential and Commer- cial/industrial classes of customers, 1 r, E"I 1 I i r { f r i 1-j i 12 I 1 +i VII, ACCOUNTING SYSTEM RECOMMENDATIONS The objective of this section of the report is to inform City officials and otatt of the required development and implemen- tation of various systems necessary to maintain a user charge (UC) ' and Industrial Cost Recovery (ICR) tariff structure under the Environmental Protection Agency (EPA) guidelines, Specifically, the following systems must be developed or current systems modified: ! { - A work order/time reporting system to collect and record Operating and maintenance (0&M) costs by the categorises of assets and therefore by volume, Biological oxygen Demand (BOD), Total Suspended Solids (TSS), and phos- phorus, ` A fixed asset recording system which separates plant and i other capital assets into the costs associated with ~ r, volume, BOD, TSS, and phosphorus. Modifications of the existing accounts receivable, interdepartment expenses, ? and depreciation procedures may be necessary to ensure w, proper handling of receipts and outside 0&M expenses, Modifications and expansion of the current customer monitoring will be required and is discussed in detail in ( Appendix Of ! An industrial cost recovery accounting system to bill and ! collect fundsfor Industrial. users based on their silo- i cabltR portion of the treatment plant. Once the funds are collected the TC;R system must segregate and track all -i investments and interest receipts by portion applicable to the EPA, the City of Denton restricted replacement account, and the City of Denton general account, ! i The establishment of a chart of accounts for a separate ~LJ enterprise fund for the Wastewater Collection and Treatment system is required. »3 9 3 i f S r L.. 13 ~.J o , rw+ x Schedule 1 rh CITY OF DENTON E ~i WATSR/_ WASTEWATER COST OF SERVICE STUDY WATER/W_ ~ EW TFR REVENUE 2I REM NTS ; FISCAL YEAR ENDING SEPTEMBER 30, 1978 Treated f, k p.} Total water wastewater Operating and Maintenance 1,194,565 S 997,189 $ 2,196,754 Expense n 680,817 458,598 222,219 ; Debt Aerviae ~ f 2121344 140,919 710425 I ~x Capital Outlay Ckpital Outlay Operating 1460840 161,000 54,160 Fund 482404 3~ 6~ 2fi4 - 1O 9 5 Return on System Equity , f Total Revenue L 4, 645=3 i Requirements X73 2 268 7 ~ j f' Net Investment in water/ f wastewater Pboilitiee lS Z,218~1 e.4___38_62~: 2 77 509 ri }e 1 Seuroea City of Denton i err .1ltr. ,,..,tr }+~yt,~~ k 1 rn➢ M ~S 0 0 G V ~ ~~w!+ rt pyI d r"r y ~ ~ , H pp0 H i~ roggq M m rt N g ro 0 tow I „ y N 0 fp E ; e t~DI ^r s ,V► fir? ~ I . w ~ N J ~ , W -4 -4 -4 F1 F^+ Zh O q O 0 V _ 1 LA J C Gah 00 Uw! 1[f E i 5 IA M . I I ~ yry~~ w f-+ w oo der ho . a N I I C W C I Vet O y! f f \ ti y twi t ~ W 0 Q ~ lW!! q t7 1 , U1 a a CY Pe O , ` 111 N 'N 7777 00 0o I n a 1 4 I I ~e~y day. rMa ~cl ~ I i I I 1yw/~ t ,,rl ~ ~ , ~ I ~j ~ Vr YI Yr V 0~0 , ~ I N to J ►J F s- H E N N di 0 W O C Co~d LA Op d Q 401 JJ ~ u~ ~ a a a a a° a a] 14 14 ki 4% 14 46 z atnp~yp5 ~ S :x~+uns X': _ -k ''-e IItNfN ~fl4VAY1 7Y.h14y ? 1 k~Wt{ Sahec~uie 3 j CITY QF DENTIN r- i t,'~, ESmTMATED REVENUE RE UXREM,_,_ENTg r ~ FOR WATER/SEW~kt SYST~':MS ,I . }twh i . , 197 7_1978. J.978-19'9 i979~-19A0 i,r• r operating. and Maintenance $ 2196,754 $ 2,416,.429 $ 2,658,072 1 ~x~ense , ' i , , ~ ~ petit services 69x,617 fi71,367 b78,567 1 Ex,iati.nq 93.,750 194,000 1~ , i ! ~ r^t Nc,a Finant~ing , ,373, 344 373 X344 373,344 ~ i...) Capital outlay Fund.. ~ . i i ~ 2, 404 4____-_~95,, 325 53~ a ' r-7 Return an system Equity 1„~ . I matal :sstimdte9 Revenue f 1 ~ . Requirements 3 733 319 4 0~ 50215. 4 as38~953 f ~ .I l~ I' ~ tYA I ' i 4~ t i • ~ ~ ~ 1 ~ F ~i ~ , : : 1~' ) ~ , . ~ , : ~ i 1 {.l gnueaes Gity c7E UAnton rl i l' r+ z 'i` . .,t ,I 1{' .._i. 1. _ - t• ~ 1 n r .u,:1x of 1 s. r.A J, Il rl. a4l f..r£.`•. q..~f 1'-..rf da- .f lib ~ti~l/fiS~Y~~~}~~ i~ t . il. y1-I 1aAlYl1~'.at..f .r. M1~.. i t ,f• ' I`ll i ` ~ - WAMCM tjp7$~ 1' r, u Schedule 4 CITY AF DENTON , ESTIMATED DEBT SERVICE COVERAGE YTATER WASTEWATER COST OF SERVICE STUDY i In FISCAL, YEAR ENDING SEPTEMBER 30 2978 C;. r rh s ~~,r 2977-1978 2978-1979 ~ Reoalnmen e urren Reaommen e lI ~r Rates Fates Rate-es t Total, Revenues 3 22 $ , 2,558 $ 31491,387 $ 4,106004 I r; Lesst ' ! Operating and r Maintenance Expense 2,1961754 Depreoiation 7,196,754 5 4,729 2/416/479 ( 1 } Interest 554,728 605917 R _ 325 817 325,11617 I 5 44O,llg Operating Income 45,259 414,088 l Flue! 683,540 Miscellaneous Income 450000 45 004 j (Al Interest lkpense 326 817 451,000 , t ueprea.lfltiot! 55 325417 440,128 -._IL , 2y 6- .05+. g27 Income Avallable for - Coverage 970 804 1339 633 1 734 Current Yeau Debt { l garvioe ado 8l7 680 817 765 2 7 Current Coverage 1.43 ) t 1. 1 2 ' .1 1 11" , Gil~ MAXIMIxm Year Dobt 88rviae 84 845(1) 842 45(1) 7 r Maximum Year Coverage l r 1 7R l,. (1} Assuming City issues $2060400 25-year bond @ 6o254 January 4 (2) 198Assuming City issues $2,500,OOtl 25-year bond 0 6.254 January ; 1,980 i Mil wrt4a1!:N Schedule 5 CITY OF OENTON ESTIMATED STATEMENTS OF CHANGSS IN FINANCIAL POSITION WATER/WAS2'EWA'PER COST OF SERVICE STUDY FISCAL YEAR ENDING SEPTEMBER 300 1978 1977-1978 19 8-1979 !a Curren 6oommen a Reaommen e4 t Rates Rates Rates Souroog of-Funds Operating income S 45,259 $ 414,088 $ 683,540 Depreciation 554,728 554,728 605,917 Miscellaneous Tnaome 45,000 450000 45;030 J Bond `Proceeds , 2, 0.40, 000 t metal Sources 664,987 1,013,816 3,334,457 I j r Application of Funds Budgeted Capitri outlay 212,344 212,344 6831637 f Bond Funded Additions 10144,538 ` . Reduotwd in Long-term Debt 355,000 355ob00 365,000 Transfer from Bond 1 1 Reserve to Fund 35,000 350000 35,000 I l Transfer to general Fund 42,643 160,404 345►325 1 9 6 7 Restricted Capital Punch 161,000 ~ Total Appliaationo 644,987 943,748 3,184,457 Net Change in Working f ,j 150 0 f~ Capital 70,008 L 1 3 1. r. ' t 4; 0 i L'1 ! ! - 1.=' J"T .:ef W a [~eFN5k r rt ro a ' A s, ~ a r7 Aft A+~ 1 I ' i ~L }I+ pp~~ 00 N Of co Ilk. i7 . JkA A 1j ~ V l~ll ~ 01 N loll n. s i H JA t 46 46 J, l g ~Ynp~4o8 ~ i IJ l-j } ~Ww WM,-A R,:I,,>, Schedule 7 CITY OF DENTON I i 1 I~ WATER/WASTEWATER COST OF SERVICE STUDY I PROPOSED WATER RATES ! Residential Customer charge $ 2,10 per month 0 - 10000 gallons $ F90 per MGAL 10,000 - 50,000 gallons $ .75 per MGAL Above 50,000 gallons $ .70 per MGAL , CommercialZindustriai C,uStOmtlr charge $ 5600 per month r~ Volume charge $ ,68 per MOAL i.; Sales for Resale customer charge $93900 per month Volume charge $ o61 per MGAL Utility Oporatione f Customer charge $ 3435 per Onth f I Volume charge $ #90 per MGAL I k CitY Acc=ounts Customer Charge $ 6,95 per 'month` Volume charge $ 90 per M15AL Electric Steam olant $ 12 per MGAL ~ fI Ira to f f Ik } CC , ~){i i 1 Ir fiF~~s~ j9ie1~ Ow TiAw.,Nv , Schedule 8 { CITY OF DENTON i ILLUSTRATION OF CUSTOMER IMPACTS RESIDENTIAL TREATED WATER RATES i 3r Monthly { Treated Monthly Monthly monthly # r Water Current Proposed zn0rease Consumption Rate Rate (Decrease ! 0 $ 3.25 $ 2.10 115) 20600 3.25 3.90 .65 5,p00 5,20 6160 1.40 10,000 8.45 11.10 2.65 1.5,000 11.70 14.85 3. ~ 15 20000 14495 18.60 3165 30,000 20.45 26.10 5.65 400860 25.95 33.60 7665 { 50,000 31.45 41,10 9+65 75,000 43,95 58.60 144, 65 t,~ 100,000 56,46 76,10 19465 I 150,000 81,46 111.10 29465 11 Lam' 3 .i r j 4 LJ S('~i uy1 MOM hi'HV~1 r•'- } ,s:WIv 8ohedule 9 CITY OE DENTON rrE ILLUSTAVON OF CUSTOMER IMPACTS i COMMERICAL/INDUSTRIAL TREATED WATER Monthly i Tr.eated Monthly Monthly I r Water Current proposed Monthly Consumption Raite Rites 7noreame ' 0 $ 5.00 $ 5,00 $ 21000 5100 6.36 ' 1.36 ri 50000 6.95 8,40 1145 10,000 10.20 11.80 1460 150000 13.45 15024 1,75 s 20,000 16.70 18660 1090 i 30, 000 2;!.x0 25.40 3 * 20 40,000 27,70 32.20 4050 i r" 50,000 33.20 39.60 5480 1 7,50000; 45070 56.00 10430 100,000 $8 .20 73400 14.80 1500000 83,20 107.00 2.$080 f, 2500000 133.20 17540 41080 4-~ 350,000 183.;0 ' a 24340 59.90 ~ 450o000 233.20 311.00.. 7.7490 ~ 4..1 A I ~ ' i .y s~ : SI + tiff f'+~ Schedule 10 + CITY OF DENTON WATER/WASTEWATER COST OF SERVICE STUDY_ FUNCTIONAL ALLOCATION OF SEWER `COST OF SERVICE i I rFISCAL YEAR ENDING SEPTEMBER 30, 1978 i Amount BOD SS Volume Functional Allocation of ~r Sewer Service Expenseas operation and Mainte- - nanoe $ 382,164 $ $ $ 3821,164 ! Treatment of Sewage 501,764 2251794 175,617 100,353 n Total 883,928 225,794 175,617 482,517 , Debt Services i Collection 246,798 146110798 Treatment 750421 18,885 11,313 45,223 i~ (J Capital Outlay Fund 54,160 - - 541, 160 Return on Net, Investments i.: Collection 781,946 - 78,946 y Treatment 40,594 10,149 6,0.89 24,356 3$ 9.3601'9 8352,_440 ' 11279,847 518 I I 686 t.a Customer Related Expenses 184, t 'Dotal Cost of Service $ 1,464,533 5 LJ i 'I: 1,a' ..:u• ,r a.. i. ..e tllnf . ,.Ll ltrya.: 1,.p an a. l , t e, r. w S rf ~l~~,t{ 1,l IV, ~n ru; Sohedule 11 ± 1 CITY OF DENTON , WATER/WASTEWATER C05T OF SERVICE STUDY i COMPUTATION OF USER CHARGES 3 j Residential User Rate BOD 240 $.000393 $ .0943 SS 240 $.000397 .0953 { Volume 1,000 $.345 .3454 Total Residential User Charge Per MGAL .5346 { Mounded c 1 j Commercial/Industrial User Rate . I ROD 260 $.004x93 $ .1020 09 260 $.000397 .1034 ~ Volume 11000 $,345. .3450 Tbtal Commerdfal/Xndu(jeri:al User Charge P6r'MGAC, .5500 33 { ( i P q tr ,r.r..-.... , . i;.rp1.y ).}..a! ae.. .'?i .xx t rrl, .r~. i anar„:1, Schedule 12 CITY of DEN_ TON WATER/WASTEWATER COST OF SERVICE STUDY f PROPOSED SEWER RATES Residential r^ 0 - 1,000 gallons, $ 2,95 per month t~ Above 2,000 gallons $ .53 per MGAL Return flow factor of 988 May - September use second highest `I nonirrigational month for calculation of bill Commercial 4,00 gallons ~ $ 5.00 per month Above 4 # 000 gallons $ .60 per Man E„ Return flow factor of 808 ; Sales far. Regale $ .58 per MdAL } City Accounts $ i58 par MEAL y M 1 Effluents 86 les to Steam Plant $ .12 Del: MOAti I! 1 i 1 I r i r,. i r.rv ry:e. tue. o `r i. .1 .'ntl. a< f\ ..r re.. . ' ' in{LAC[ u>v s cwrn ' AVIV-b Schedule 13 CITY OF DEN TON PROPOSED INDUSTRIAL SURCHARGE I Cu = Vu ((au - 260) S + (Su 260) S) , Where: Cu is the surcharge for user.X Vu is the billing volume for user X Su is the tested SOD level for user X or 260 mg/l, which- It ever is greater S is the unit cost factor for treating one unit'of SOD per 1,000 gallons ($.000393) Su is the tested SS bevel for user X or 260 mg/10 which ever is greater y S is the unit cast factor for treating one unit of SS ~ per 1,;100 gallcns-($.000397) I It t thl i P ,ip 14-V Schedule 14 i CITY OF DEN'TON ILLUSTRATION OF C4MMEtCTRL IN[1USTRIAL CUSTOMER IMPACTS 1 BEER RATES t Monthly Treated Monthly Monthly Monthly F Water Current proposed Increase Cansuropion _Rates~ Rates (Decrengel 0 $ 5100 $ 5100 $ a 1 I ~l 20000 5.00 5100 ' r A 5,000 6.26 5.00 ( 2'6) i` 10,000 8.36 7,40 ( .96) 150000 10446 9680 { ,66) 20,000 12;56 12.20 [ 30,000 16,76 1740 .24 ♦'8.tl E ~,4 40, 000 2140 21480 ~ 50,000 25,16 26.60 Is 44 75,000 33,1.6 38.60 5,44 1000000 41.16 50.60 9,44 150,000 57.16 74.60 17.44 2500000 89,16 122.60 33.44 350,000 121,16 170,60 49.44 4500000 153.16 218.60 65.44 M• 1 , ~ WIM r 1 k rt TI,: {rSAaVr ,WrIyN n... rat .l;v , I 1 i.i, r .1 a. .~II l.rylYl J•:,1 /1 a15 a t..r 11 r , ~S IRi'LCW1 i r~ S'{$1}! SahedUle 15 CITY OF DENTON TLLUSZ'RATTpN OF REOIDENTIAL CUSTOMER IMPACTS SEWER RATES s Monthly Treated Monthly Monthly Water Current Proposed Monthly Conaum tion -Batas _ E Rates Increase I (1 $ 2175 $ 2.95 $ .2U 21000 2.75` 2.95 .2Q 5r00 0 il 4401 4.49 f 10,000 5.81 7.08 1.27 _ 150000 5081 9.68 3.87 t i 20,000 5.81 12428 6.47 ! 3Qt000 5.81 17,47 11.65 ; .i 400000 5.81 22.67 16686 f $0,000 5.81 27'.86 2245 ( Y5~bOb 5,81 40,85 35.04 t 100,000 5.81 53.83 48.02 k ' 150400 5.g1 79.90 73.99 i ! 1 } .Y r `}A, I4 °➢iiti _l y i ~ App~i'DIX A r j , i ! . x Jf, 7 f ~ ~I { „ N S ILLUSTRATIVE INDUSTRIAL WASTEWATER ORDINANCE The following illustrative ordinance was prepared as a'guide to aid City officials in the development of an Industrial Waste- water Ordinance. We recommend that the City attorney's office and utility officials review the illustrative ordinance and make those modifications which may be required due to legal interpretations or the procedural goals of the City. r SECTION Is DEFINITIONS' { d Unless the context specifically indicates otherwise, the { meaning of terms used in this ordinance shall be as followss BOD (denoting Biochemical Oxygen Demand): The quantity of oxygen utilized in biochemical oxidation of organics matter under standard laboratory procedure in five (5) days at twenty (20) degrees centigrade, expressed in parts per million by weight. ~ j .r Building drains That part of the 'lowest horizontal piping ! r drainage system which receives the discharge frost soil, waste and other; drainage pipes inside the wal,~ls of the building and oontdeys it to the building sewer, beginning five (5) feet outside the inner face of the building walla > ° Building Sewers The extension from the, building drain to jj the public sewer or other place of disposal. 9 1,j Director of Utilities: The person omployed as Director of Utilities for the City. Garbagea Solid wastes from the domestic and commercial reparation, cooking and dispensing of food, and from the handling, storage, and sale of produce, Industrialwastes: The water-borne solids, liquid or gaseous wastes from industrial manufacturing, processes, ' ! trade or business as distinct from sanitary sewage Natural Outlets Any outlet into a water course, pond, ditch, lake, or other body of surface or 4rou0d water, persona The word "person" shall extend and be applied to ass;ooiates, corporations, firms, partnerships, clubs, agents, truatebae reneivers, and body politic incorporate as well as individualso pHs The logarithm (base 10) of the reciprocal of the hydro- gen ion concentration of a solution. f } za tr]YbL.I J 3C1 Matt t V'i'..U rur~Ai;p 1 d" tuc,w I Properly shredded garbagei The wastes from the preparation, cooking, and dispensing of food that has been shredded to such a degree that all particles will be carried freely under the flow conditions normally prevailing in public sewers, with no particle greater than one-half (h) inch in any dimension. Public Sewers A sewer in which all owners of abutting properties have equal rights and is controlled by public J authoity. Sanitary Sewers A sewer which carries sewage and to which i storm, surface, and ground waters are not intentionally admitted. 1 sewage$ A combination of the water-carried wastes from residences, business buildinga, institutions, and indus- trial establishments. Sewage Treatment Plants Any arrangement of devices and structures used for treating sewage. Sewage works: All facilities for collecting, pumping, C treating and disposing of sewage. sewers A`pipe or conduit for carrying sewage: ! r Storm drain (sometimes termed "storm sewer")s A sower which ; carries storm and surface waters and drainage, but excludes i „I sk, sewage and industrial wastes, other than unpolluted cooling water. r ~ t SS (denoting Suspended Solids)s Solids which either, float on the surface of,, or are in suspension in water, sewage, or other liquids, and which are removable by laboratory filtra- tion _i wator+"~ourses A channel in which a flow of water occurs, r° either continously or intermittently. SSCTIoN III USE OF THE PUBLIC SEWERS i . (A) NU person shall discharge or cause to be discharged any ' storm water, surface water, ground water, roof runoff, subsurface 'drainage, cont4minated cooling water, or unpolluted `industrial process waters to any sanitary Newer. (S) Storm water and all other unpolluted drainage shah, be discharged to such sewers as ere specifically-desig- T nated As storm sewers or to a natural outlet approved by the Direbtoe of Utilities. Industrial cooling water Or unp~.lutod process waters may be discharged, on a a i of the Director of Utiliti.ge, to a storm sewer ' or natural outlet, or into a sanitary sewer system upon prior written approval of"the Director of Utilities, ..,...LL„ ark" 1 (C) No person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewersr I- ( (1) -Any gasoline, benzene, naptha, fuel -oil, or other ! flammable or explosive liquid, solid, or gas, r r (2) Any wastes or waters containing objectionable car toxic substances, or wastes exerting an excessive r chlorine r6quirement, including but not limited to the followi.ngr (a) Any mercury or phenols greater than five- 1\ thousandths (0.005) part per million by l P weight, 1 (b) Any antimony or beryllium greater than one- hundredths (0,01) part per million by weight, f (c) Any cadmium or selinium greater than two- } r7. hundredths (0.02) part per million by weight', (d) Any arsenic or chromium (hexa) greater than five-hundredths (0.05) part per million by weight. II - h i (e) Any lead or silver greater than one-tent (0,l) art per . ~ p 1? million by weigh t, , i. (f) An iron' Y greater than three-tenths (0,3) part J per million by weight. I Ion ' (g) Any bismuth' greater than r "e-tenths (005) part per million by weight'. (h) Any cyanide greater than one (1) part per million by weights as CN j (1) Any boron, cobalt, copper, manganese i i molybdenum, nickel, or tin greater than one f (1) part per million by weight, (3) Any barium, chromium (tri)o uranglion, or zinc greater than five (5) parts per million by weight, (k) Any radioactive wastes greater than allow- L r~ able releases as specified by current O'nited states Bureau of Standard Handbcoka dealing with the handling and releases of radio- activit,y, i _J to- 9:YSLd4~- ry j (D) No person shall discharge or cause to be discharged the following described substances, materials, wat'ers# or wastes if it appears likely in the opinion of the Director of Utilities that such wastes can harm either the sewers, sewage treatment process or equipment, have t an advorse effect on the receiving stream or can other- wise endanger life, limb, public property, or consti- tute a nuisance. In forming his opinion as to the acceptability of these wastes, the Director of ' Utilities will give consideration to such factors as I the quantities of subject wastes in relation to flows and velocities in the sewers, materials of construction of the sewers, nature of the sewage treatment process, } capacity of the sewage treatment plant, degree of treatability of wastes in the sewage treatment pplant, and other pertinent factors. The substances prohibited area i (1) Any waters or wastes containing strong 'acid iron piokling wastes or concentrated plating solutions f f whether neutralized or not.. (2) Any waters or wastes containing objectionable or toxic substances, or wastes exerting an excessive a chlorine requirement, including but not limited to 1, the following: F (a) Any mercury greater than five-thousandths (0.005) part per million by weight. I i` (b) Any cadmium or selenium greater than two- hundredths (0.02) parts per - million° by ; G-± weight. I , r~ (o) Any arsenic greater than five-hundredtha ' (0.05) part per million by weight. (d) Any lead or silver greater than one-tenths (0-1) part per million by weight., (e) Any cyanide' greater than one (1) part per ' million by weight, as ON. (f) Any baron, hexavalent chromium, copper, 4 manganese, nickel, or tin greater than one (1) part per million by weight. (9) Any barium, iron, or zino greater than five l (S) parts per million by weight. 1 (h) Any trivalent chromium ggreater than ten (10) _parts per million by weight (i) Any phenols greater than twelve (12) pacts k per million by weight, u 4YNk%ar 1 i ' (j) Any radioactive wastes greater than .allow- able releases as specified by current United 1 States Bureau of Standard Handbooks dealing with the handling and releases of radioactiv- ity. (3) Any waters or wastes containing whole blood, (4) Any waters or wastes having nth in excess of ten i (10). (5) Materials which exert or cause: (a) Concentrations of SS in excess of two hundred and sixty (260) parts per million by weight, (b) Exceusive'discoloration, (o) SOU greater than two hundred and sixty (260) parts per million by weight. (d) Average daily `volume of flows j greater than ~ five (5) percent of the average daily sewage flow of the City, ; (6) waters or wastes containing suostanoes which are , not amenable to treatment or reduction by the sewage 'treatment processes employod, or, are amenable to treatment only:tb such degree thdt the t sewage treatment plant effluent cannot meet the. j requirements other agencies' having Jurisdic- tion over discharge to the reoeiving waters, t (E) if any waters or wattes are discharged) or are proposed + to be discharged to the public sewers, which waters ) Contain the substances or possess the characteristics + L. enumerated in subsection (D) of this veetion, and which in the judgment of the Director of Utilities, may have a deleterious effect upon the sewage works ' , processes, ; equipment or receiving waters or which otherwise create a hazard to life or constitute a public nuisance the 4 7 Director of t1til.ities mays (1) Reject the wastes, ' (2) Require pretreatment to an acceptable condition for discharge to the public sewers, } '...I (3) Require control over the quantities and rates of ~l discharge, and/or ^Z (4) Require payment to cover the added cost of hanw `J dl ng andd treating the wastes. t II ~.3 $74N14, 1 SECTION 1111 PRETREATMENT OR EQUALIZATION OF WASTE FLOWS j (A) if the Director of Utilities permits the pretreatment or equalization of waste flows, the design and instal- lation shall be subject to the review and approval of E the Director of Utilities and subject to the require- ments of all applicable codes, ordinances, atisd laws. (B) Greaser oily and sand interceptors shall be provided for the proper handling of liquid wastes containing grease in excessive amounts or any flammable wastes, sand, or other harmful ingredients: except that such interceptors. shall not be required for private living quarters or dwelling units, All interceptors shall be constructed of impervious materials capable of with- standing abrupt changes in temperature; shall be of substantial construction, watertight, and equipped with easiy removable covers which when bolted in place shall be gastight and watertight; and shall be located as to be readily and easily accessible for cleaning and . inspection. (C) Where preliminary treatment or flow-equalizing facili- i I.J ties are provided for any waters or wastes, they shall ' be maintained continously in satisfactory and effective ( operation by the owner at his expense. w SECTION IVs SURCHARGE If the Director of Utilities permits the acceptance of ,.y wastes of abnormal strength or character, for treatment, a t surcharge calculated as follows shall be_added to the basic sewer charge to cover the added cost of handling and treat- ing the wastes: .J industrial surcharge Cur Vu ((Su - 260) B + (Su - 260)S) , E ~ Where: w.` Cu is the surcharge for user x Vu is the billing volume for user x au is the tested BOO level for user x or 260 mg/1r whichever is greater B is the unit cost: factor for treating one unit of Bon per 11000 gallons 01000303) z fi,E Su,is the tested sS level for user x or 260 mg/11 whicho'ver is greater S is the unit cost factor for tretl'ting one unit s of SS per I,Ooo gallons ($.000357) Biannual review of the surcharge factors shall be made and shall be the basks for periodic adjustments to the surcharge, . d, w SECTION Vt INDUSTRIAL WASTE PERMIT (A) Any person discharging or proposing to discharge to the public sewers industrial wastes, which contain the ~ substances or possess the character is ice enumerated in j section II herein, shall make appliciation for sewer connection to the 'Director of Utilities on a form to be r" furnished by the city. ! (H) The following shall apply to persons discharging indus- trial wastes to the public sewers on the effective date ' .i of ordinance Number of , 1978r r (1) Application shall be made for sewer service within ninety (90) days of the effective dates (2) Within thirty (30) days of receipt of the applica- tion the Director of utilities will furnish the applicant his opinion as to i4oceptability of the. wastes. (3) If the wastes are riot acceptable in the bpi4ian of € the Director of Utilities, the surcharge specified II in Section IV herein shall become effective thirty t (30) days from the date of the opinion furnisher) the applicant. This durcharge shall continue until acceptable corrective measures are taken or sewer service discontinued. I~"{ (4) If the Director of Utilities finds that the wastes # C should be rejected, requires pretreatment; or flow-ennaliiation the applicant will be a ed ' eighteen (18) months from date of "initiate of ? the surcharge to, provide correotive measures to i r" make the wastes acceptable. r~ (C) persons proposing to discharge industrial wastes to the publio sewers subsequent to said effective, date shall ' make application 'for sewer service to the Director of Utilities at or prior.to the time of application for ,a plumbing permit under the Plumbing Code. Within thirty (30) days of receipt of the application; the Director t of Utilities will furnish the applicant-his opinion as j to acceptability of the wastes. A plumbing permit shall not be issued until sewer service is approved. SECTION VI t MPECTION, SAMPLINO~ HMSU9XN0, AND TESTING ' INDUSTRIAL WASTES 1 (A) When required by the Director of Utilities, the owner of any property serviced by a building aewer carrying industrial wastes shall install a suitable control manhole together with push necessary meters and other appurtenances in the building sewer to facilitate observation, sampling, and measurement of the wastes. 1 ' f F 3rd F >1 1, i r 11 ~ - earn.,, ELl2~.9n Such manhole, when required, shall be accessibly and safely located and shall be construoted in accordance with plans approved by the Director cf Ut.illtiea. The manhole shall be 'installed by the owner at his `expense and shall be maintained by him so as to be sjafe and accessible at all times. ` (s) All measurements, toots, and analyses of the oharaoter- istics of waters and wastes to which reference is made' in this ordinance shall be determined in accordance with the latest edition of "Standard Methods for the } Examination of Water and Waste Waterr" published by the j American Public Health Association,aod shall be deter- mined at the control manhole provided or upon suitable samples taken at said control manhole. In the event Illl that that no special manhole.. has been required, the ;I ` control manhole shall be considered to be the nearest q r~ downtown manhole in the public sewer to the point at f which the building sewer is connected. Sampling shall be carried out by customarily accepted methods to E I reflect the effect of constituents upon the sewage t works and to determine the existence of hazards to IJ life, limb, and, property, The.. particular analyses i involved wi11 determine whether a twtnty-four (24) hour Y i composite of'outfalls of a premises is appropriate or I whether a grab sample should be taken. (C) The Director of Utilities and other duly authorized ill k employees of the City shall be permitted to enter all ' properties for the purposes of in4pection, observation, measurementsampling, and testing in accordance with the provisions of this article. SECTION V11i AUTHORITY TO DISCONNECT SERVICE, 1 t E Any person found to be discharging to public sewers any of the prohibited industrial wastes set out in Section II shall be served by the City with written notice stating the nature ! of the.violation. The Director of Utilities is authorized to immediately disconnect the offending person's sewer service upon such notice and to not reconnect it as long as the violation continues. ; , . i t i i it ~J!I F F.rS's?.1 ) 1 L' r f r ~ "PUDIX 13 ~ i r i I { -Ink j oft, CUSTOMER MONITORING PLAN GENERAL DISCUSSION j j2 TRODUCTION Numerous discussions were held with City officials during this engagement relating to the design and development of a customer ' lonitoring plan. Through these discussions the City expressed that tiny large scale plan would be too costly for the City to implement. w We concur that a large scale monitoring plan probably would be too costly for the City to undertake based on the number of _commercial and industrial consumers present within the City of E Dentin. However, we believe that a general, discussion should be pros>snCed in order that the City officials are aware of the Environ- mental Protection Agency (9PA) requirements regarding customer monitoring. i r LEGTSLATM RE U2REMENT POR_CUSTOVMR MONITORING rx The EPA guidelines indicate that each customer must pay a sewer charge which is proportional to that customer's use of the N&nitaxy sewer facilities. This proportionality of rates may be the most baio EPA prerequisite for grant eligibility. Paragraph 204(b) of Publjo Law 92-500 states "..:that each recipient of waste treat.- 1 meat services Within the applicants' juriadiotida...wili pay its proportionate share of the costs of operation and:maintenance '(in- ; cludingreplaaement) of anyy waste treatment services provided by ; E ' the applicant..." The guidelines provided by the EPA tot compliance with PL92-500 further stipulate that individual charges should be updated periodieally~ Those two provisions, proportionality Of rates and periodic updating of the rates, are major reasons for the EPA xequirament for an adequate monitoring system. ;ths EPA guidelines further ntate that the proportionality moat be maintained by periodic review.' An annual review of the proportionality is suggested in the guidelines. under these guide- lines, annual review would be required by customers who are newly connected to the sewer system, of customers oho change their effluent "J oharacteristios, or of those customers who are disconnected from the k system. Changer in the O&M expenses Would aido have to be reviewed periodically. E r rr , rd , lr4i Now- -IMF IIWAI 17 j r The EPA requirements result in a need for these types of systemsi - An administrative system for collecting and analyzing data (including the calculation of proportional tariffs). A customer identific&tion system for the main- tenance of information regarding the number and types of sewer customers. . - A sampling and testing program for determina- 71 tion of the customers' effluent characteristics. While each of these systems is necessary, it appears that the EPA (in our experionoe) considers that both a plan for develop- '».0 11 ) meat of, these systems and evidence of implementation of this plan i i as being adequate for satisfying the construction grant requirements. i RMXNXS'TRATIVZ SYSTEM l,~ The customer identification and sampling programs must be coordinated. The primary purpose and objective of the:administratl.ve system is to provide coordination satiotication to the EPA Region vI staff, that proportionality is being established and maintained. The calculation of tariffs is the major rel;ult of the administrative function. The calculation of tariffs is, of course, the necessary and product of the entire monitoring program. Tariff desi n► how- evert encompasses functions beyond the scope of a monitoring program. E ; For example, the monitoring program may be intended primarily; for the industrial poet recovery (ICR) part 61 the guidelitaes. CONS IDERAT IONC IN A TYPICAL MONXTORINO PROGRAM t The EPA states that proportionality of rates should be • based on the coat of building and operating a plant, Every plant has certain t es of pollutants <that 'it is "intended to treat. These pollutants arameasured as they enter the plant so that when new plants are designed the total level of pollution from all cuertom6rs may be xranrlatsd into design criteria. Each customer should (accord- ing to JPA) pay for their share of the pollution '.(and volume of "J wastewater), raaohing the plant. Pro~pbrtioAslity of rates, therefore, y requires "hoiderable knowledge Of t e sources of pollution entering } 4J the sewer s,j,~)tam. some sewage enters the system through leaks in the sewer lines, from damage to the sewage collection lines, from improper constrvationr from inadvertent combination of otorm sewers and sanitary sewers, and fron several other sources. Since this source 'of pollution is general and in characteristic of all sewer r. i f : fit:;:. , ~ ~ • - fi~/ i WON 1 J swy ~ul i:XYFL IC.J■ Pt. !lt9.i tn4 , I systems, the cost of treating pollution such as thin is referred to as infiltration and inflow (I&I). I&I may typically account c for 208 to 408 of the volume of wastewater reaching the treatment plant. The monitoring plan is not typically designed to measure or estimate i&I. A major one time only engineering study is frequently i:. necessary to quantify 24I. A monitoring program includes two major types of effort: j customer identification and testing of samples of customer effluent. ! Pollution provided by one customer, or one identifiable source', is i called point source pollution. The monitoring program theoretically identifies each point source within the sewer system and provides III reasonable data for estimating each point source's proportional share of the total cost of the sewer system. The data required for a monitoring program includes the identification of the customer, 1 f the type of customer (i,e, residential or business), the type of business if a business customer, the location of a suitable sampling s E point such as a manhole, the volume of wastewater discharged by the ! i customs r, the average biochemical oxygen demand (SOD) of the se the phosphorus level, said the average suspended solids (TSS) Ob» taining;this data for all customers would be an expensive, time con- I`] sliming and somewhat redundant project, There are some assumptions and estimates that are appro- priate in designing a proper monitoring pprograms One example of a simplifying assumption is in the identification of customers. Many s customers have effluent with similar pollutant characteristics and can be grouped into a single customer class. Each customer class 1 F is then treated as a single, large customer when determining pro- ) portionali.ty. The basis for grouping euatomere into a class may be industry-wide effluent averages, past sample testing results, state- wide or regional data, or other justification that can be documented. Some examples of customer ngs, classes are: residential, office buildi health care institutions, service stations, supermarkets, restaurants and schools, tach customer class contains only customers with similar effluent characteristics (900 and Ts9). The monitoring program also provides a means of obtaining representative effluent samples from every major customer or customer class. This of course requires knowing.exactly where customers are ' ! connected to the collection system, where manholes are located and r 3 what time, of day an adequate sewer flow will be available for sampling. Grab samples may be used for monitoring as long as care is taken to } avoid scraping material from the manhole of the walls of the sewer main, Another method of sampling which is frequently used for large f.I customers is a mechanical sampler which may obtain samples over a 24 hour period. Thost devices usually require a rather large manhole. cleaning of the manhole is advisable before installing the mechanical sampler. ti rcy 1.( r1 'Yr NFSA4d p 4iy?:~ip[uj YJ r,, Ti Another step in the monitoring program is the careful iden- tification, bottling and transport of a sample to the testing labor- atory. Care must be taken to maintain the temperature of the sample within certain ranges or the SOD test results will be affected. The identifioation and documentation of the source and conditions under, which the sample was obtained is necessary to provide adequate back- up for tying a sample to a specific customers In some extreme cases the test results must be good enough to be legally admissable evidence. More likely, the sampling documentation will be used to convince in- dustrial customers that test results are valid. Er? The testing procedure must be appropriate. Adequately trained staff must be employed and a laboratory equipped to provide all the necessary tests. The testing procedures must be supportable in the event of an EPA audit. Because customer's effluent characteristics change and a ` Customer's: rate may change each year, there must be an adequate sys- tem for providing customer service. Customers would reasonably want to see the data upon which a sewer rate relies. This suggests a sys- tem of documenting both the samples and the test results for perhaps Vrm several years for each customer or customer class. This requirement may be changed as better data becomes available. An exauaple of ' changes necessitated by better data is the identificationof a new oustomer class that previously was included, with other customers. CURRENT SYSTEM MONITORING During our review of operating systems we noted that the City has a limited customer monitoring system installed. The Waste- water'Collection and Treatment System is ourrently monitoring the major industrial users within the City. These industrial consumers are being sampled using basically grab samples. Presently the City of Denton sanitary sewer system does not have the necessary manhole locations for proper sampling/metering of all commercial consumer groups. j RW,9#21ENDAT IONS We recommend that the City of Denton consider implementing a wider based sampling system during future years of servicA. We believe a system which would allow for larger numbers of customer groups `would `be beneficial to both this City and its ratepayers. To achieve an expanded customer classification may take a number of years and will probably have to be completed in 'phases. Recommended steps for Implementing an expanded monitoring system are as follows: . Review all commercial and industrial customers connected to the City of Denton sanitary sewer system to identify possible now customer classes and respective sampling requirements. I' f _ t 11 --T TIT 141 K4 rww Review the current sanitary sewer collection system in order to identify all potential sampling sites existing in the system. _ j Assure that new industrial and commercial develop ments have adequate sampling sites installed during construction of new facilities. if this require- meet is instituted then a data base of sampling results will begin to develop ovei the future years, , • f ~ ,Y I $ , rr ~ ~ Y4 r 7xa ("'I { t Y L , j 301 rat ~ ~ r t rr ~ ~ , w . v e r 1£t 5 L f i :i N i i f f N rd 5.. S r _ d % {aaQ~ mt~esw[: , 3 j f i f ? °1 j art! f e ~ , EEI ,f l 11 I. 4" I , E a ~ ~ i f1~Fq t ~ .l~' ~ ~ I i s s ' i r . s l . r 1 I. Cf[~ v[le 1 „ t t Fm 4 f E i C) F 1 { i I L IE~ ill { /