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Home My WebLink About; Water Master Plan; Master Plan Updates; 1997-10-012.1 2.2 CARLSEAD MUNICIPAL WATER DISTRICT VOLUME 111 WATER MASTER PLAN MASTERPLANUPDATES TABLE OF CONTENTS Paae No. Introduction ................................. ............. 1 1.3 Purpose and Scope of Work ........ ....................... 1 Chapter 2 Water Demands .............................. ............ 3 Chapter 1 1.1 Previous Studies . . ........................ 1.2 Sources Consulted ...... ................... Historical Water Demands. .............................. ..................................... Land Use ..... ........................ Average Annual ... ....................... 4 Potable Water Demand ....................... .......... 4 .......... 4 Ultimate Demands ..................... ...................... 5 Maximum Day Demand ...................................... ......... ............. Chapter 3 SelviceAreas .......................................................... 8 3.1 Boundaries .... ................................. 8 3.2 Pressure Zones .......................... .......... 700PressureZones ........................ ........ 680 and 580 (La Costa) Pressure Zones ............. ............ 550 and 375 Pressure Zones ................................... 11 490PressureZone ......................... .......... 580.446 and 349 Pressure Zones ..................................... 12 318 Pressure Zones ... ................. .............. 14 255 and 330 Pressure Zo .......... Chapter 4 Existina Facilities .................... ......... 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 .. Water Sources ............................ ......... San Diego County Water Authority Turnouts .... ............ Emergency Water Supply ............... ............... ........... ..... .................................... ia ....... .......... ......... ia Volume. ................................. ............. . . 18 CathodicProtection .................................................... 19 Distribution . . ....... .................................. 19 ............................... 19 .......... ................................ 19 Booster Pump Stati .......... .............. ............. 20 ............. ........... 20 ................. ........... 21 ....................... 21 Disinfection Facilities ....................................................... 22 Hydro Generation Facility ........................................ . 22 Chapter 5 WaterQuality ......................................................... 23 5.1 5.2 5.3 5.4 5.5 5.6 Background ........................... ............... 23 Existing Regulatory Requirements ..... .............. 23 Impacts of the 1996 Amendments ...... .............. 24 Specific Requirements ................... .............. 24 Trihalomethanes ..................... .............. 24 Total Coliform Rule (TCR) ............ ................. 25 State of California Drinking Water Regulations DisinfectantlDisinfection By-Products Rule (DIDBP) .... ................. 2a Long-Term DlDBP Rule ........... Enhanced Surface Water Treatment Rule (ESWR) ............ Arsenic Rule .................... ..................... 32 Groundwater Disinfection Rule ..... Sampling Points ... .............. .............................. 32 Water Quality ................... .................. 33 Lead and Copper Rule (LCR) ......... Surface Water Treatment Rule (SWTR) ...................... ......................... Anticipated Future Regulatory Requirements .............. 2a ... Additional Rules ...................................... District Water Quality ................. Disinfectant Residual ............. ........ MWD Operations ........................... ........ Ozonation .............................................. Colorado RiverIState Proiect Water SD F- Chapter 6 System Modeling ..................... ..................... 36 6.1 Modeling Criteria ................... .............. 36 Friction Factors (Hazen Williams "c" Coefficients) ..... ........ 6.2 HydraulicAnalysis ......................................................... Storage ................................................ Base System ........................ Model Calibration ...................... Results ...................... Testing and Calibration ................. .............. 37 Chapter 7 Capital Improvement Plan .............. 7.1 Storage Requirements ..................... Existing Storage Requirements ..... ............... 39 IO-Day Emergency Storage Requirements ..... .......... Ultimate Storage Requirements ......... 7.2 Recommended Improvements ....... Pipelines .............................................. Pumpstations ......................................... Resewoirs ........................................................... 41 7.3 Estimated Costs .................... ................. 41 Basis of Costs ................. .. Capital Improvement Projects ............................. TOC - 2 ,-- Table NL 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 List of Tables Paae No. ............ . . Chapter2 ............. Water and Land Use. ... a. Average Daily Dema b. Large Volume Users. ............... Peaking Factors . ................. .................. Historical Maximum Demands ......... ....... Design Fire Flows .......... ............ Summary of Each Pressure Zone Pump Station Summary ................ Existing Distribution Storage Reservoirs ........ Model Calibration Summary ......................... ........ Chapter 6 Existing Storage Requirements Per Pressure Zone ......................... Chapter 7 Ultimate Storage Requirements Per Pressure Zone ................ Capital Improvement Summary .............. ................ Average Daily Demands - Ultimate Conditions ........ Chapter 2 ........... 6 ....... ...... Source Supply Flow Summary ....... ....... ....... PRV Summary Table .... ................ ........ Chapter 4 Capital Improvement Program ........................ ........ Chapter 7 List of Fiaures Figure N& 1 Average Daily Demand Per Month - 1991 to 1996 ..... .. ......... Chapter 1 3 Pressure Zones ......................................... 2 VicinityMap ............. ..................................... Chapter 1 4 Hydraulic Profile Schematic ................. ......... Chapter 3 5 Population and Housing Units . .............. 8 Maximum Day Demand Diurnal Curve ........ ......... Chapter 6 9 Hazen Wllliams "C vs. Pipe Age ............. ................. Chapter 6 10 Existing System Operational Storage Requirements ................. Chapter 6 I1 Capital Improvement Program ... ................. Chapter 7 6 Historical Maximum Day Deman .............................. 7 Existing Pipelines 14-inch and Larger Distribution Map ..... REFERENCES TOC - 3 J:\z237W01 Wstrplan.wpd ABBREVIATIONS Abbreviations used in this report are as follows: ADD ac AC AF CfS CIP CMWD CWA DU EWPCF fPS GIS gPm HGL HWL MD MDD MG MHP MWD No. PH PHD PRV PRVlPSV PSV psi PVC R.O. RN SANDAG SDCWA SCADA TAP VFD WD WRF mgd Average Day Demand acre Asbestos Cement Acre Foot cubic feet per second Capital Improvement Program Carlsbad Municipal Water District County Water Authority Dwelling Unit Encina Water Pollution Control Facility feet per second Geographic Information System gallons per minute Hydraulic Grade Line High Water Level (maximum water surface elevation in storage tanks) Maximum Day Maximum Day Demand Million Gallons Mobile Home Park million gallons per day Metropolitan Water District of Southern California Number Peak Hour Peak Hour Demand Pressure-Reducing Valve Combination PRV and PSV Pressure Sustaining Valve pounds per square inch Polyvinyl Chloride Reverse Osmosis Remote Terminal Unit San Diego Association of Governments San Diego County Water Authority Supervisor Control and Data Acquisition Tri-Agency Pipeline Variable Frequency Drives Water District Water Reclamation Plant TOC - 4 1.1 Previous Studies The most recent water master planning document for the Carlsbad Municipal Water District (CMWD) was completed in June 1990 and revised in December of 1990 by MacDonald-Stephens Engineers, Inc. The Master Plan was approved and adopted January 29, 1991 by the City Council. This current master planning effort for CMWD incorporates the following updated information from the 1990 document: An overall decrease in the purchase ofwater from 1990 to 1995 from the San Diego County Water Authority, of 13.6 percent. 0 0 r 0 0 An overall decrease in domestic water sales of 12.5 percent An increase in recycled water sales to 1,418 acre-feet (AF), representing 7% of the 1996 potable water demand. Completing Phase I of the Twin "D reservoir with added storage capacity of 8.5 MG and converting the existing D-1 and D-2 reservoirs to serve recycled water customers. Potable water demand decreases in certain pressure zones due to the conversion of irrigation customers to recycled water. 1.2 Sources Consulted The basis for this update were the most recent development plans and land use planning documents. The basic planning document consulted were the Local Facilities Management Plans prepared by the City of Carlsbad Planning Department. Each of the 25 Local Facility Management Zone (LFMZ) documents were either in various stages of completion or completed at different dates. These documents were based upon the Carlsbad General Plan which was completed by !he Planning Commission in April of 1994 and adopted by the City Council on September 6. 1994. Also consulted were the most recent updates of San Diego County Assessor's Maps and 1995 Thomas Bros. Guide Aerial Maps in order to inventory existing development and to assess potential buildout densities. 1.3 Purpose and Scope of Work The purpose of this Water Master Plan is to revise and update the 1990 Water Master Plan and to incorporate current population projections, new City of Carlsbad planning criteria and specific project development plans. The plan identifies the facilities required to Serve existing and projected potable water demands within the service area and adjacent areas of influence. This Water Master Plan includes a phased improvement schedule recommended for ultimate development of the study area, including expansion of the water reclamation system. In this study, the terms reclaimed water and recycled water are ? synonymous. Recently, there has been a trend to use "recycled water, where "reclaimed" water has been used in the past. The scope of this effort, as contained in Appendix A, Volume I, Environmental Setting, reflect and incorporate the following items: 1. 2. 3. 4. 5. 6. 7. Relevant data from the June 1996 LFMZ Development Plans. Environmental Characteristics: Provide general information on City of Carlsbad and CMWD and summarize objectives, methods, and documents. Land Use: Discuss Carlsbad General Plan and it's impact on the water system. Also summarize land use and resulting demands for water using existing and 20 year projections. Current and future water supply sources including operational and emergency storage. Inventory of existing water system components and recommended improvement program to meet future water needs. Discussion of current water quality standards and future options. Preparation of a hydraulic computer model of CMWD's water system. 2 J:V237\001 \Mstrplan.wpd Chapter 2 Water Demands I 2.1 Historical Water Demands General This section presents the land use'and develops the associated annual average potable water demand based on land use. Water demand factors for average day, maximum day and peak hour demand are estimated based upon past consumption and historical water demands. The potable water demand incorporates all uses including irrigation, and assumes that the recycled water system is not used to reduce the water demand. Land Use Current and future water demands are greatly influenced by land use classifications. For example, residential areas have a different water demand than industrial zoned development. In addition, fire flow demands vary depending on the type of development being protected. Land use data was supplied to ASL by the City of Carlsbad Planning Department. This data was supplemented with 1995 aerial photographs used to determine existing developed areas. The residential units (single and multi family) were counted by using the aerial photographs along with CMWD Water Atlas Sheets, San Diego County Assessor's Maps and individual Local Facility Management Zone (LFMZ) Growth Plan Reports provided by the City Planning Department. The land use data is divided into single family units, multifamily units, agricultural acres, industrial acres, irrigation acres, and commercial acres. Each land use category is tabulated by water system pressure zone and LFMZ area with existing and ultimate land use tabulations summarized in Tables la and lb. - The commerciaVindustrial class includes governmental, utility, educational, and classes of mixed use development. Such as C/O - Community CommerciallProfessional and Related; PlIO - Planned IndustriaWOffice Related; and RHICIO - High Density ResidentiaVCommunity CommerciaVOffice and Related Commercial. Single family classes refer to single residential units while multi-family classes include condominiums, duplexes, and apartments. Irrigation users are scattered throughout the City without a separate zoning designation and include agricultural, golf course, and industrial uses. The location and amount of irrigated acreage was tabulated by Carollo Engineers as part of their recycled water study. The agricultural areas and locations were determined from zoning information, aerial photos, and information provided by the CMWD Metering and Billing Department. The only exception to this is for estimating the agricultural water demand. Agricultaral water demand was approached by reviewing past meter records. According to the Metering Department, irrigation meters are dispersed throughout the City and are used for the landscaping in industrial parks, commercial centers and roadways. Affer consultation with the metering personnel, reviewing meter records, and reviewing future recycled water sites, the amount of irrigated agricultural acreage was determined. r Average Annual Potable Water Demand Historical water demand data was provided by the CMWD in several forms. The first source Of information included summary charts of water demand from 1991 to 1995 in one hundred cubic feet units (CCF). This inforpation was separated into monthly water demands for agricultural, commercial, industrial, multi-family, single family, and irrigation uses. According to the water duty method for fiscal year 1995 - 1996. the average daily demand was 12.57 mgd. The breakdown of average daily demand (mgd) per month for 1991 to 1996 is shown in Figure 1. The most recent Water and Sewer Rate Study for CMWD, by the Water Resources Planning Department completed in September 1994, estimated CMWD water use percentages. This study was completed for all member agencies of the San Diego County Water Authority to assess future water and sewer demands. This compares closely to the water duty demand factor method estimated in this Master Plan. The primary differences occur in the public and "other" category of the Water Rate Study which are larger than the current estimate. This decrease in demand is due to the increased use of recycled water in those categories. Because of the increased use of recycled water, the residential water usage percentage increased. The difference behveen the quantity of water produced and that sold is unaccounted for water. In most waterdistribution systems, thebulk of the unaccounted forwater is due to systemlosses, such as leakage from the distribution system piping, meter inaccuracies, and unmetered water consumption (fire fighting, street cleaning and construction uses). Totaling all of the classifications the Average Daily Demand (ADD), excluding recycled water, for the period of January 1996 to December 1996 was 13.84 mgd. The average rate of water purchased by CMWD for fiscal year 1994-1995 was 13.75 mgd. This amounts to an unaccounted amount ofwater of 5.45 percent. This percentage of unaccounted water has been added to ultimate future demands in order to predict the amount of water to be purchased from the CWA Recvcled Water The City of Carlsbad has adopted an ordinance requiring the use of recycled water if available. Presently, there is more demand than supply. Alternatives for increased recycled water supply are evaluated and presented in Volume IV Recycled Water.of this Master Plan. The CMWD began delivery of recycled water in the fall of 1991. This program has grown. and over 1,400 acre-feet of recycled water was used in the calendar year 1996. The expanded use of recycled water was evaluated in this Master Plan Study. However, in order to make sure the ultimate potable water system has adequate storage and pipelines, the ultimate potable water system plan presented herein does not include recycled water. This was done in the event that there is no further development of the recycled water system beyond its current state. Sources of recycled water include thevallecitos Water District's Meadowlarkwater Reclamation Plant and Leucadia County Water District's Gafner Water Reclamation Plant. These facilities can provide up to 2.75 mgd during the peak irrigation month of September. CMWD purchases the recycled water from these agencies through long-term agreements. Major users include La Costa Resort and Spa and the Aviara Resort Golf Course. Other users include CALTRANS landscape irrigation along Interstate 5, Poinsettia Community Park, and other landscape irrigation uses. Larqe Volume Users The second source of information for historical water consumption was obtained by reviewing the usage of large volume users for each classification over the period of July 15, 1995 to November 15, 1996 (17 months). Table 2 shows the top five (5) users in each classification for the period specified. As shown in Table 2, the largest CMWD customer is the La Costa Hotel and Spa. It is served by a 4-inch domestic irrigation meter, located to the east of El Camino Real by the lakes on the northern end of the La Costa County Club Golf Course. There are also four (4) other commercial use meters serving the La Costa Hotel and Spa complex. Two other large volume users of note are the Lanikai Lane and Solimar Mobile Home Parks (multi-family) which are both located in the southwest area of the City, each using an average of 14.0 gpm for the reported period. Ultimate Demands The ultimate demands were estimated by calculating the ultimate buildout of the City as detailed in the 1994 General Plan. The ultimate population vs. housing unit can be seen in Figure 5. In general, the older northwestern portion of the City is near buildout while the remaining areas are at various stages of development. LFMZ areas 17, 18. 16, 13. and 25 are at present, virtually undeveloped. Each zone's individual growth plan outlines future dwelling units and non-residential acres. Table 1 b presents ultimate water demands and conditions with recycled water sources not included. Two water consumption classifications will drastically change in the future. These are the irrigation and agricultural uses as these demands will decrease as recycled water systems are developed. The same demand factors used to calculate the existing average daily demands (ADD) were also used to determine the ultimate ADD. The proposed development data was input according to current zoning designations and LFMZ growth plans. Maps were provided by CMWD showing the locations and pressure zones of future piping. Using this map and available topographic information, future development was assigned a pressure zone and LFMZ. 2.2 Peaking Factors Peaking factors are commonly utilized to estimate annual, daily, and hourly fluctuations in water demands. Through the use of these factors, the impact of a peak water demand on the distribution system can be estimated. For the purposes of this report. three peaking factors have been considered. Each peaking factor is utilized individually to assist in the sizing of facilities required to meet the peak demands. /- Three different time related demands, average day, maximum day, and peak hour, have been identified and utilized throughout this report. These factors are summarized in Table 3, and are described as follows: Average Day Demand (ADD) Maximum Day Demand (MDD) Peak Hour Demand (PHD) II Description I Factor 1 .o 1.65 2.50 Maximum Day July 27, 1996 * June 21.1995 July 19. 1994 July 20, 1993 September 3,1992 July IO. 1991 Average Day Demand MGD 19.9 20.99 21.96 21.38 31.48 24.10 Y The average day demand is the average demand for one day during the calendar year. It is measured at the water supply sources and is equal to the total metered demand of all the sources during the calendar year divided by 365. It is expressed in terms of million gallons per day (MGD). In 1995 the average day demand, including recycled water, was 12.75 mgd. Maximum Day Demand - The maximum day demand (MDD) is defined as the highest demand for water experienced for a one day period during the calendar year. For CMWD, this high demand day typically wrs in June or July. The maximum day demand for 1995 was 20.99 mgd. The maximum day peaking factor is a ratio of maximum day demand to the average day demand. For 1995 the peaking factor is 20.99 mgd12.75mgd = 1.65. This figure compares almost identically to the peaking factor of 1.67 estimated and used in the 1990 Master Plan. Table 4 shows the historical maximum day demands. The historical maximum day demands are shown graphically in Figure 6. ,- Peak Hour Demand Single Family Multi-Family COMMERCIAL INDUSTRIAL INSTITUTIONAL The peak hour demand (PHD) is defined as the highest demand experienced during a two-hour period on the maximum demand day. Hourly demand data was provided by CMWD. The peak hour in 1996 was on July 21 with a total system flow of 34.1 mgd. By taking a ratio of the peak hour demand to the average day demand for 1996, a peak hourly demand factor of 2.50 results. The previous water master plan used a PHD peaking factor of 3.07. 1500 2 20 3000 2 20 4000 4 20 4000 4 20 4000 4 20 Fire Demands The City of Carlsbad, as stated in their General Plan, wishes to meet future fire demands in step with development and in accordance with the City's Fire Guidelines. This code adopts the 1994 Uniform Fire Code (UFC), with certain amendments and deletions as the basis for fire flow protection. The worst case condition was used for modeling purposes. Fire flow demands for the different land use categories are shown below in Table 5. All fire flows are measured with 20 psi residual pressure at the fire hydrant. .- II Land Use I DesianFire 1 Duration 1 Residual 11 7 Water and Land Use: AVERAGE DAILY DEMANDS MlSTlNG CONDITIONS MASTER PLAN ADD = 1211 MG MDD wlhmg Ikw I67 W&randLanduSe: 10 %Sum@ Rqdmmu = 10 x ADD = IZI, I MG AVERAGE DAlLY DEMANDS WsTlNG CONDITIONS &LSA (-)=Womrgemm (+) =*mnprnzm TABLE 1 a 'ASL Consulting Engineers CARLSBAD MUNICIPAL WATER DISTRICT Water and Land Use: AVERAGE DAILY DEMANDS UL77W7E CONDITIONS ADD = 23.58 MG MDD &am 1.67 10 Bq Smw5 Eyximmb = 10 x ADD = 235.m MG MASTER PLAN Water and Land use: AVERAGE DAILY DEMANDS f-)=Wwmm (+) =S@?am5mznr TABLE1 b 'ASL Consulting Engineers LARGE VOLUME USERS Notes: 1) Class Designations are ar follows: A-Agricultural; C-Commercial; I-Industrial, IRR-Irrigation; INST-Institutiunal; MF-Multi-Family 2) Periodfor consumption data is 7/1J/95-11/15/96 (I 7 Months) MASTER PLAN LARGE VOLUME USERS TABLE 2 ASL Consulting Engineers CARLSBAD MUNICIPAL WATER DISTRICT 1 - Chapter 3 Service Areas I 3.1 Boundaries The CMWD service area for potable water is shown on Figure 3. The CMWD service area covers approximately 85 percent of the City of Carlsbad and includes an area of about 32.1 1 square miles. It is bounded by the City of Oceanside on the north, Vista Irrigation District and Vallecitos Water District on the east, and Olivenhain Municipal Water District on the South. 3.2 Pressure Zones The existing CMWD Water System is organized into pressure zones according to the hydraulic grade line (HGL) served. The CMWD has a redundant system because the flow from the highest pressure zone (700 Pressure Zone) is able to service the next lower pressure zone, continuing until the lowest pressure zone (255 Pressure Zone) along the Pacific Ocean is reached. Wth the flow traveling by gravity from east to west, various Pressure Reducing Valve (PRV) stations are located throughout the water system and serve to separate the system into various pressure zones and to service successively lower elevations. Figure 3 shows the pressure zones and Figure 4 is the hydraulic profile schematic showing interconnections and sources of supply for each individual pressure zone. The following sections provide a brief narrative description of each individual pressure zone and Table 6 summarizes the data for each pressure zone. The pressure zone discussions have been arranged starting with the higher HGL zones in the east and proceeding westerly to the lower HGL zones. 700 Pressure Zones Santa Fe II Zone and La Costa Hi Service Zones Land Use and Planning The primary land uses in these pressure zones are industrial, residential, and agricultural. The agriculturally zoned area is now being developed. The first development under construction is a planned development called Carrillo Ranch with a build out of 1,500 single family homes. Subsequent development being planned includes the Bressi Ranch property and the Bank of America property referred to as La Costa Greens. These areas are all south of Palomar Airport Road. The portion of the pressure zone north of Palomar Airport Road is zoned Industrial and is referred to as Carlsbad Oaks North Business Park. This pressure zone is located within LFMZs 5, 16, 17, and 18. Referencing the LFMZ planning documents for these zones, the ultimate number of residential units and nonresidential acreage was estimated. Water Demand The maximum day demand for the existing land use is 0.45 mgd and is shown in Table la. Future demands will increase for industrial and residential uses with the water demand for agricultural uses decreasing. The ultimate MDD in the zone is 2.28 mgd and is shown on Table lb. 8 c Existing Water System The 700 Pressure Zone@) are supplied by the SDCWA CMWD Connections No. 1 and No. 2 shown in Figure 3 and described in Table 6. The water is delivered at an HGL of over 1,000 feet and can flow into the 9.0 MG Santa Fe II Reservoir (HGL 700) and the 6.0 MG La Costa Hi (HGL 700) Reservoir. The water is then distributed by gravity. In the future, the Santa Fe II and La Costa Hi Reservoirs will be interconnected by a pipeline which will provide redundancy for emergency supply. This pressure zone is currently not able to receive emergency storage from the Maerkle Dam due to Maerkle Dam being lower in elevation at HGL 490. The Santa Fe II Reservoir serves the 550 HGL Zone through PRVs located at the intersection Of Palomar Airport Road and El Camino Real. The La Costa Hi Reservoir serves the 680 Pressure Zone through a PRV located on Alga Road. Storage for the 700 Pressure Zone@) are provided from two reservoirs. The Santa Fe II Reservoir has 9.0 MG storage capacity with a floor elevation of 700 and height of 32-feet to HWL. The La Costa Hi Reservoir has a capacity of 6.0 MG and a height of 27-feet to HWL. Existina Pressure Reducina Valves There are currently lwo PRVs separating the Santa Fe 700 Pressure Zone from the 550 and one PRV separating the La Costa Hi 700 Pressure Zone from the 680 Pressure Zone. These valves are Cla-val combination PRVand Pressure Sustaining Valve (PSV), whoseoperation is described in a latersection. In the future there will be two other connections to the 550 Pressure Zone from the 700 Pressure Zone at the intersections of Faraday Avenue and future El Fuerte Drive and El Camino Real and future Poinsettia Lane. Also planned is a 16-inch PRV connection to the 490 Pressure Zone from the 33-inch Maerkle Reservoir line. Existinq Distribution Svstem The South Aqueduct and the Palomar Airport Road pipelines branch off from the SDCWA Second Aqueduct and into the Santa Fe II and La Costa Hi Reservoirs, viaVallecitos Water District, respectively. These and the remaining 14-inch and greater diameter water lines within the system are shown on Figure 7. Ultimate Distribution Svstem The ultimate distribution pipes for the 700 Pressure Zone convey water from south to north and east to west. The proposed east to west transmission line will be a 16-inch main in the future Poinsettia Lane from Melrose Drive to El Camino Real. The proposed south to north transmission lines will be a 24-inch main along Melrose Drive, a 24-inch main from Palomar Airport Road to the future Poinsettia Lane, a 30-inch main from the future Poinsettia Lane to Alga Road, and a 16-inch main north of the Palomar Airport Road industrial complex which in the future will be connected at the most northern part to a 16-inch line in Melrose Drive that runs to the 490 HGL connection. 9 J:\223Mo1 U4strplan.wpd - PumD Stations There are no pumping stations in the 700 Pressure Zones. However, to enable water stored in Maerkle Dam to be supplied to the 700 Pressure Zone, it is necessary that a pump station be planned and constructed to boost the pressure from 490 to 700. This future pump station could be located at the intersection of Palomar Airport Road and El Camino Real. 680 8 580 (La Costa) Pressure Zones Land Use and Planning The 580 (La Costa) Pressure zone is an isolated and fully developed zone in the La Costa area and has been included with the 680 Pressure Zone for analysis of storage needs. The zoning designations for both the 680 and the 580 South Pressure Zones are entirely residential. These zones are located to the west of the La Costa Hi 700 Pressure Zone, and border the OMWD and WVD. These areas are not expected to significantly change with future development. The pressure zones are in LFMZ 6 and the ultimate number of residential units was obtained from the LFMZ 6 Planning document. Water Demand The water demand based on the ultimate land use is shown in Figure lb and makes up the total demand for the zones. The ultimate maximum day demand is 0.38 mgd for the 680 Pressure Zone. Existing Wafer System The zone is supplied by the La Costa Hi 700 Pressure Zone through several PRV stations. Table 6 summarizes the supply and demand facilities. The water is distributed by gravity to their respective servicezones and in the future these zones will be able to receive emergency storage from the Maerkle Dam by constructing the 700 Pressure Zone pump station. - The 680 Pressure Zone supplies the 580 (La Costa) Pressure Zone through two PRV stations. The 680 Pressure Zone also supplies the 510 Pressure Zone through PRV stations on Alga Road and El Fuerte Street. Storaqe The zone has no storage and relies on the 6.0 MG La Costa Hi Resetvoir in the 700 Pressure Zone to meet all operational storage needs. Existinq Pressure Reducinq Valves Currently, one PRV separates the 700 Pressure Zone from the 680 Pressure Zone. There are three PRVlPSV valves separating the 680 and 580 (La Costa) Pressure Zones. There are two PRV stations separating the 680 and 510 Pressure Zones. These stations are shown on the Hydraulic Profile Schematic (Figure 4) and are described in the PRV Station Summary Table 10. 10 Pump Stations There are no pump stations within either the 680 or 580 (La Costa) Pressure Zones. 550 and 375 Pressure Zones Land Use and Planning The zoning designations for the 550 Service Zone is primarily industrial and commercial. The 550 Pressure Zone is in LFMZ 5 and includes the McClellan Palomar Airport area and the surrounding industrial, business, and research parks. It is projected to add additional industrial and commercial acres in the future. The 375 Pressure Zone, north of Palomar Airport Road, is primarily industrial and mostly undeveloped in LFMZ 20, and also includes parts of LFMZ 5. Future development will include residential and limited industrial expansion. Proposed developments include the Legoland Theme Park with accompanying hotels and shops, and an artificial man made lake. Future potable water demands within this zone will increase greatly for commercial uses and decrease for irrigation and open space uses due to the utilization of recycled water. The 375 Pressure Zone, south of Palomar Airport Road, lies north of the 31 8 Pressure Zone in LFMZs 19 and 9 and is primarily residential with additional residential development planned for the future. Existing Wafer System The 550 and 375 Pressure Zones are supplied through PRV stations from the 700 Pressure Zone. Table 7 summaribes the source of supply and receiving CMWD reservoir facilities. The water is distributed by gravity to the respective service zone. Currently these zones receive emergency storage from the Maerkle Dam. - The 550 Pressure Zone also supplies the 375 Pressure Zone through three PRV Stations (College West, 'D" Reservoir and Palomar Oaks). The 375 Pressure Zone in turn supplies water to both 318 Pressure Zone and the 255 Pressure Zone. The 375 Pressure Zone is supplied by the Twin "D reservoir (HGL 375) with a storage capacity of 8.5 MG. This reservoir was constructed in 1996 with chlorination facilities and replaced the D-1 and D-2 Reservoirs which where converted to recycled water use. The site was graded and property acquired to accommodate an additional 8.5 MG of storage to be constructed at a later date. There is one PRV Station connecting the 550 Pressure Zone with the 490 Pressure Zone on Faraday Avenue. I The water demands for the existing and ultimate land uses and development patterns are shown in Tables la and 1 b. The ultimate maximum day demand for the 375 and 550 Pressure Zones are respectively as follows: 6.12 and 1.95 mgd. 11 I 490 Pressure Zone Land Use and Planning The 490 Pressure Zone is in the northeastern quadrant of the City of Carlsbad and to the west Of the City of Vista boundary. All existing land use designations are agricultural. Water Demand The water demands (ADD) for the existing and ultimate land uses and development patterns are shown in Tables la and Ib. Future demands will increase as the area is developed for single family and industrial uses. The ultimate maximum day demand for this zone is 1.64 mgd. Existing Water System The 490 Pressure Zone is supplied by the SDCWA to Carlsbads No. 3 connection as shown in Figure 4. The imported water is delivered at an HGL of over 900 feet to the dam and then reduced in pressure through a series of PRVs. - This pressure zone has two reservoirs for storage needs. One is the Mearkle Reservoir with a capacity of 10.0 MG and a height of 24.5 feet to HWL. The Mearkle Dam has a capacity of 196 MG and serves as emergency storage. Existinq Pressure Reducinq Valves The 490 Pressure Zone supplies the 446 Pressure Zone through four PRV Stations. The 446 Zone also is a primary feed for the 255 north and tow mobile home parks located in the 3301325 Pressure Zone. PumD Stations A new pump station with (3) 150 Hp. 7,000 gpm capacity pumps will be put into service once improvements to Mearkle Dam are completed in April 1998. 580,446 and 349 Pressure Zones Land Use and Planning The primary land use designation in these three pressure zones is residential, with minor isolated areas of commercial usage. The 580 Pressure Zone is in the northeastern quadrant of the City and east of El Camino Real within LFMZs 2 and 7. The 446 Pressure Zone is on both sides of El Camino Real and is in LFMZs 2 and 7. The area is zoned for the planned development of Calavera Hills (Villages Q. R, and T) single family homes. The 349 Pressure Zone is in LFMZs 5. 16. 17. and 18. J:u237u)01 \Msttplan.wpd 12 - Water Demand The water demand (ADD) for the existing and ultimate land uses and development patterns are shown in Tables la and 1 b. The 349 Pressure Zone is an isolated zone within the 446 Pressure Zone. Future demands will increase in residential usage and decrease in agriculture usage. The ultimate maximum day demand for each zone is 1.34 mgd for the 580 Pressure Zone, 1.92 mgd for the 446 Pressure Zone, and 0.36 mgd for the 349 Pressure Zone. Existing Water System The 580 Pressure Zone is supplied by the SDCWA via Carlsbad No. 4 connection as shown in Figure 4. The imported water is delivered at an HGL of over 900 feet and flows directly into the 580 Pressure Zone or into the TAP Reservoir (HGL 446) via two pressure sustaining vaults. One sustains to CWA No. 4 connection and the other to the 580 Pressure Zone. The water is then distributed by gravity to the 446 Pressure Service Zone (serving all of the pressure zones in the northern part of the City). The 580 Pressure Zone also receives water from the 446 Pressure Zone via the Calavera pump station in emergency situations. Because the Maerkle Dam spilhay is at elevation 500, emergency storage can be supplied to the 580 Pressure Zone through the pumped 446 Pressure Zone. Storaqe - The 446 Pressure Zone storage is provided by the TAP Reservoir which has 6.0 MG of storage capacity and a floor elevation of 446-feet and height of 28-feet to HVM. The TAP Reservoir serves all zones in the nolthwestern portion of the City via PRV Stations. The reservoir is one of three prestressed concrete reservoirs built in 1985. The 580 Pressure Zone does not have storage capabilities; however, in emergencies it can be served by way of the Calavera Pump Station. This pump station currently has no electrical service and must be run using a 125 KW portable generator which the CMWD owns. The 580 Pressure Zone, 446 Pressure Zone, and the 349 Pressure Zone are supplied through the TAPINo. 4 connection. All PRVs and normally closed valves within thezones are summarized in Figure 4. Existina Pressure Reducina Valves There are four PRV Stations separating the 490 and 446 Pressure Zones. The 446 Pressure Zone also can supply the 255 South and 349 Pressure Zones through PRV Stations. Pump Stations The only pump station in any of the zones is the Calavera Pump Station. This station has two 75 Hp pumps, each with a capacity of 1,500 gpm. The station is used in emergency situations. 13 J:V237\001 Wstrplamwpd ,- 318 Pressure Zones Land Use and Planning The zoning designations within the 318 South Coastal and 318 La Costa Lo Prt3Ure Zones are primarily residential and commercial. The zone has two mobile home parks and other multi-family areas. The Pressure Zone is bordered by the 375 and 255 Pressure Zones, Batquitos Lagoon to the south, Pacific Ocean to the West, and the 510 Pressure Zone to the east. This area is zoned primarily residential, and includesthe Carlsbad Car Country development. This pressurezone falls within LFMZ's 4, 9, 20, and 22. The La Costa Lo is the most southerly part of the City and encompasses the La Costa Country Club, La Costa Hotel and Spa with single and multi-family residential units. This pressure zone falls within LFMZs 6 and 19. Water Demand The water demands (ADD) for the existing and ultimate land uses are shown in Tables la and 1 b. The ultimate maximum day demand is 3.5 mgd for the westem portion of the 318 Pressure Zone and 7.89 mgd for the eastern portion of the 31 8 Pressure Zone. Future demands will increase for industrial areas and residential areas with the demand in agricultural areas decreasing due to rezoning and increases - in reclamation use. Existing Water System The westem portion of the 31 8 Pressure Zone is served by two PRV stations (Las Ondas and Poinsettia) from the 375 Pressure Zone. The westem portion of the 318 Pressure Zone can also supply the 255 South Pressure Zone through a PRV station located along Encina Boulevard. The eastern portion of the 318 Pressure Zone receives water through a primary PRV station from the 510 Pressure Zone and it can also be supplied from the 550 Pressure Zone at El Camino Real with backup PRV supply from the 510 (Bolero) and 375 (Blackrail) Pressure Zones. Storase The zone has the La Costa Lo Reservoir for storage purposes. The La Costa Lo Reservoir is located off of Alga Road and has a capacity of 1.5 MG with a height of 38.5 feet to the HWL. The reservoir must be able to meet the minimum capacity requirements as discussed in Section 7 concerning system storage. Existinq Pressure Reducinq Valves L Presently, two PRVs separate the 375 Pressure Zone from the westem portion of the 318 Pressure Zone and they are located on Camino De Las Ondas and Poinsetta Lane. The eastem portiin of the 31 8 Pressure Zone's main PRV is located on El Fuerte and the PRV station from the 550 Pressure Zone is located off of El Camino Real. The backup PRVs are located on Bolero (from the 510 Pressure Zone) and Aviara (from the 375 Pressure Zone). - Pump Stations There are no pump stations within either pressure zone. 255 and 330 Pressure Zones Land Use and Planning The 255 Pressure Zone above the Agua Hedionda Lagoon covers most of the downtown area and is bordered by Buena Vista Lagoon on the north, the 330 Pressure Zone on the east and the Pacific Ocean on the west. The 255 Pressure Zone land uses consist of the village area, single and multi-family residential, and commercial areas, all located entirely within LFMZ 1. A mobile home park and the Encina Power Plant are being developed for commercial uses east of Paseo del Norte and north of Palomar Airport Road. The 330 Pressure Zone is also located within LFMZ 1 and is comprised of residential and institutional (Carlsbad High School and Junior High School) uses. Water Demands The water demands (ADD) for the existing and ultimate land uses and development patterns are shown in Tables la and 1 b. The maximum day water demand for the existing land use is 7.06 mgd for the 255 Pressure Zone, and 1.37 mgd for the 330 Pressure Zone. The ultimate maximum day for the 255 Pressure Zone and 330 Pressure Zones are respectively 9.21 mgd, and 1.33 mgd. Existing Water Supply System The 255 Pressure Zone has three existing reservoirs, the 1.5 MG Elm Reservoir on Carlsbad Village Drive, the 1.5 MG Skyline Reservoir on Skyline Road and the Buena Vista (0.01 MG) emergency tank located on Buena Vista Drive and the 1.5 MG "E" Reservoir located near Hidden Valley Road. The total existing storage volume within the zone is 4.5 MG. The 330 Pressure Zone storage needs are met entirely by the 5.0 MG Ellery Reservoir fed from the 490 and 446 Pressure Zones. - The 255 Pressure Zone is supplied by the Elm Reservoir, Skyline Reservoir and the "E" Reservoir, within the zone and by way of two PRV stations feeding from the 330 Pressure Zone. The 255 South Pressure Zone is supplied alternatively through a PRV station from the 375 Pressure Zones (the 255 South Pressure Zone can also be fed by a backup PRV through the 375 Pressure Zone and a normally closed valve from the the westem portion of the 318 Pressure Zone). Both zones service only the demands within their respective zones and do not meet any external zone demands under normal operating conditions. The 255 Pressure Zone can provide emergency supply 15 J:V237\001\Mslrplan.wpd - to the 330 Pressure Zone by use of an existing 10,000 gallon steel tank and 3,400 gpm capacity pump station located on Buena Vista Drive. Existina Pressure Reducina Stations The PRV stations serving the 330 Pressure Zone and the 255 Pressure Zone are located on Pine Avenue (tire Row only) and Buena Vista Way, respectively. The PRV station from the 446 Pressure Zone to 255 is located on El Camino Real and Kelly Drive and the PRVs from the 375 to 255 Pressure Zone are located on Cannon Road and Palomar Airport Road. The valve separating 318 and 255 Pressure Zone is on Avenida Encinas. These stations are listed and further described in Table 10. PumD Station The only pump station located in either of these zones is the Buena Vista Pump Station which is used for emergencies only. It pumps water from the 255 Pressure Zone to the 330 Pressure Zone. Buena Vista has a 10,000 gallon storage tank to sewe as a forebay for the pumps. The pump station information is summarized in Table 8. 16 TABLE 6 OF EACH PRESSURE ZONE SUMMAF GROUND ELEVATION SEavED 442-234 FACILITIES SUPPLYING ZONE TvplcAL HGL FACluTlEs DEMAND ZONE TAP Connection 580 Zone 476 Connection #4, in emergency from Calavera P.S. (446) PRV to 446 446 Zone 845 308-130 372 Tap reservoir and PRV from 580 (3) PRVs from 490; emergency from Ellery P.S. (330) PRV to 349; PRV to 255 349 Zone 35.3 211-3 245 Tap 446 zone 285 Zone 37 1470 242 PRV from 490 154.4 352-174 416 Maerkle Reservoir Private 318 Mobile Home Park (Rancho Carlsbad); PRV to 285 Maerkle Connection 490 Zone 330 Zone 192-14 - 256 ~ Secondary to 255 through (2) PRVs Ellery Reservoir 325 Zone 8.4 187-9 2 490 Maerkle zone 255 Palomar Airport Road and South Aqueduct Connection 2,914.3 1170 242 Elm and Skyline with secondary storage from P3. E and D reservoirs PRVs . from 318 Zone; (2) PRVs 375 and (1) PRV 318 700 Zone 184.4 196 478.6 45.2 - - - 562-384 626 680,550 zones Santa Fe II and La Costa Hi La Costa Hi From (2) PRVs 375 576 446 406 - - 680 Zone 550 Zone 510Zone 542-334 412-204 372-164 580 (La Costa), 510 To PRV 375 Zone 653.3 231-59 301 (3) PRVs from (550) Zone (2) PRVs to 255 244 = 318 Zqne ~ La Costa Lo and "D-1"with secondary sources from PRVs from 5547 and 700 Zone. PRVs from 490; secondary from (3) PRVs from 375 PRV to 255 rc 4.1 Water Sources San Diego County Water Authority Turnouts All of the CMWD's water is supplied through four SDCWA treated water aqueduct connections. The CMWD is totally dependent on the SDCWA supply for potable water needs. The CMWD currently has two SDCWA connections (TAP No. 3 and TAP No. 4) from the SDCWA owned and operated Tri-Agency Pipeline which also serves the City of Oceanside and the Vista Irrigation District. The CMWD also has two SDCWA Connections from the Second Aqueduct (PAR NO. 1 and South Aqueduct No. 2). The SDCWA Second Aqueduct connections also serve the Olivenhain Municipal Water District and Vallecitos Water District. The summary of supply sources can be seen in Table 7. As stated in Volume 11, Water Resource Master Plan, the Cii of Carlsbad has claimed rights to "underground flow" associated with surface waters within the Mission Basin in Oceanside. Groundwater that falls under "underground flow" is groundwater that is essential to the existence and preservation of a stream or river. Underground flow is treated the same as surface flow by the California State Water Resources Control Board which has jurisdiction over surface water. The CMWD has six unequipped wells located within Oceanside that have historically extracted groundwater from the Mission Basin. The wells are in place but have not been used for over thirty years. Emergency Water Supply The CMWD can be served through an emergency connection from the City of Oceanside. The connection is a 12-inch diameter pipeline located in El Camino Real at Vista Way. This pipeline is served by the 3.0 MG Henie Hills Reservoir in Oceanside at an HGL of 409 and can serve the 255 Pressure Zone (Downtown area) in Carlsbad currently meets the 10 day emergency storage requirement with Maerkle Dam. This emergency storage is available CMWD wide to all pressure zones below an HGL of 512 in the event of a SDCWA shutdown. Connection I E, No. 1 (Palomar Airport Road Connection) No. 2 (South Aqueduct Connection) No. 3 (Maerkle Connection) No. 4 (TAP Connection) "1996 CMWD Water Production I To 22 filtered Santa Fe II 10 filtered La Costa Hi Maximum Water Capacity Type Reservoir Reservoir 10 filtered Maerkle Reservoir 10 filtered TAP Reservoir & 580 Pressure Zone ata Fmm Second SDCWA Aqueduct Second SDCWA Aqueduct Tri-Agency Pipeline (TAP) Tri-Agency Pipeline (TAP) 17 J:\2237\001 \Mstrnlan.wod - 4.2 Storage Location Storage for the CMWD is currently provided by eleven enclosed reservoirs. one reservoir not in use (2.5 MG Santa Fe I) and one dam referred to as Maerkle Dam. All are above ground except for the Maerkle Dam and Maerkle Reservoir. The system was designed to be extremely flexible in its ability to transfer water throughout the District from- pressure zone to pressure zone. All reservoirs are constructed of steel except for the Santa Fe I, Santa Fe 11, La Costa Hi, and TAP Reservoirs which are circular prestressed concrete and the 10 MG Maerkle Reservoir which is reinforced concrete. Table 9 lists the CMWD's reservoirs with corresponding elevations and storage capacities. The Maerkle Dam is currently an open reservoir with a 600 acre-feet (1 95.5 MG) capacity. The reservoir is being lined and fitted with a cover and will remain temporarily out of service until these retrofits are completed in April 1998. The only zone which does not have available storage is the 580 Pressure Zone. This pressure zone is fed directly from the TAP pipeline without storage directly serving the zone. In cases of emergency, the Calavera Pump Station can deliver 1500 GPM of water from a booster pump in the 446 Pressure Zone (TAP Reservoir) to the 580 Pressure Zone. - Volume The existing operational system storage capacity is 51.5 million gallons, excluding Maerkle Dam. The effective storage of the system is actually less due to overtlow levels and hydraulic limitations. The Maerkle Dam provides emergency storage and has a spillway elevation of 500-feet and a floor elevation of 488-feet. Under normal operation the water from the dam is pumped into the adjacent reinforced concrete Maelkle Reservoir (IO MG) then supplied by gravity to the distribution system. However, not all pressure zones can be supplied water from Maerkle Dam. 18 J:U237\001 Wstrplan.wpd Water Master P Name of Reservoir TAP Ellery Capacify Low Wafer High Wafer High Water fW Level (ff) Level (ft) Level 6.0 446 473 27.0 5.0 330 352.5 22.5 Cannon "C" Skyline Maerkle Reservoir "E" 1.0 392 423 31 1.5 241 263.5 22.5 10.0 490 514 512.75 1.5 264 302.5 38.5 II La costa-LO I 1.5 I 318 I 356.5 1 38.5 11 Twin 'D" Santa Fe II La Costa-Hi fl& 'in $J, ~~ ~ Cathodic Protection None of the storage facilities currently have cathodic protection. The CMWD is planning to place a sacrificial anode system at the three (3) concrete reservoirs to protect inletloutlet piping and other appurtenant items. No other tanks currently have cathodic protection systems. 8.5 375 430 56 90 700 732 32 6.0 700 727 27 - 4.3 Distribution System Inventory The information for the existing distribution system was based on CMWD atlas maps and the Master Plan Report, June 1990. Asummaly ofthe pressurezones and the hydraulic profileschematicshowing all of the major interconnections is shown in Table 6 and Figure 4 respectively. Piping The distribution system has over230 milesofdistribution mains6-inch and larger. The 14-inch diameter and larger pipes are highlighted on Figure 7. Eightyeight percent of the piping system is constructed of asbestos cement pipe (ACP) with ductile iron (DIP), steel and polyvinylchloride (PVC) comprising the remainder. 19 J:\2237UX)l\Mstr~Ian.wcd *- The supply mains begin at each of the four SDCWA connections and move westward. The 580 Pressure Zone is fed by a line directly off of the No. 4 connection. The one classification of pipe targeted for ultimate replacement are the steel water mains installed before 1980. 4.4 Booster Pump Stations There are four booster pump stations in CMWD's system, three are used for emergency purposes and one is currently inactive. The location of each pump station is shown on Figure 3 and a summary of the pump station data is on Table 8. The 580 Pressure Zone is provided with emergency booster pumping from the Calavera Pump Station located near the TAP Reservoir. The station can provide 1500 GPM of flow to serve minimum fire flows for the residential area. The Calavera Pump Station site is not served by electricity and relies on backup generator power. The Buena Vista Pump Station has a 10,000 gallon storage reservoir as a forebay in which water is pumped to a pressure zone with a higher HGL (255 to 330 Pressure Zones). A new (3) 150 HP pump station will be in service when the Maerkle Dam comes on line and will also have chlorination capabilities. In addition to the above mentioned pumps the District has a portable pump that can be used as necessaly. 4.5 Pressure Reducing Stations A Pressure Reducing Station (PRS) provides a method of serving water between different pressure zones, from the higher to the lower pressure zone. The CMWD utilizes PRS's to reduce pressure from the higher pressure zones in the eastern part of the District to the lower pressure zones in the western part. All regulating valves within the CMWD system are Cla-Val combination Pressure Reducing Valves (PRV) and Pressure Sustaining Valves (PSV) which perform two independent functions: The PRV mode maintains the downstream pressure regardless of flow fluctuations and The PSV mode sustains an upstream pressure to a desired minimum and is normally held open. However, if the upstream pressure drops below the set minimum the valve closes. Under normal conditions the stations operate in the PRV mode. Some of the stations that feed isolated areas, particularly mobile home parks, have separation valves with a combination of pressure reduction and flow metering capabilities. An example of this is located at the Lanikai PRV. which services the closed zone of the Lanikai mobile home Dark. Some of the valves are used to maintain fire flow between zones. These valves are listed in Table 10 with the fire flow designation. The summary of all PRVs is shown on Table 10 which lists the CMWD identification number, type of valve, normal pressure setting, diameter, and pressure zones the valves separate. The major PRVs can also be seen on Figure 4, Hydraulic Profile Schematic. 20 4.6 San Luis Rey Wells CMWD owns six wells all located in the City of Oceanside. The wells were designed to pump water from the San Luis Rey groundwater basin to the City of Carlsbad. The wells were constructed by the Carlsbad Mutual Water Company which was later purchased by the City of Carlsbad and have been inactive for the past thirty (30) years because of poor water quality, approximately 500 mgA TDS. Originally. these wells were the primary source of water for the City of Carlsbad up to 1955. At that time imported water replaced the well water supply. The information reviewed for three of the supply wells, San Luis Wells 53-1, 53-3, and 56-1, also showed that each well is in poor condition due to corroded casings and deteriorated pumps and motors. Further information is presented in Water Resource Master Plan, Volume II . At this time it is assumed that these wells will not directly supply potable water to the CMWD. 4.7 Cannon Well Field The Cannon well field is located on the north side of El Camino Real, south of the Rancho Carlsbad Golf Course. The well field was reportedly developed in the early 1950s with installation of 4 groundwater supply wells (Barrett Consulting Group 1991). Boring and well installation logs for these wells were not available. The wells reportedly supplied the City of Catisbad during the years 1958 through 1962 at an average rate of 163 AFlyr (1958-1961). During the 1961-1962 period, only 16 AF/yr was pumped from these wells. Additional information concerning the decrease in well production and the ultimate discontinued useof these wells was not available. A presumed long term yield from these wells was reported at approximately 400 AF/yr (Barrett Consulting Group 1991) however, no data supporting this estimate nor the method of estimation was reported. Currently. two wells in this field are used by the Rancho Carlsbad Golf Course for irrigation water. The 1991 report states that two of the wells had been abandoned and two of the wells were inactive and in a state of disrepair. The report recommended drilling a 16-inch test well, and if successful, equipping it with a 200 gpm pump. The water would be blended with other non-potable water sources and used on a proposed golf course. The quality of this resource could be marginal. As reported for Agua Hedionda Creek, the TDS concentrations could reach 2000 mglL. The Barrett report estimated the quality ranging from 1300 to 1500 mglL. This was based on sampling of various wells located within the Agua Hedionda Creek Hydrologic area. The present quality has not been tested and is not known. Due to blending limitations, it is probable that demineralization would be required to reduce the TDS to 1,000 mglL to match the water quality of the existing recycled water system. This would result in a net decrease in the estimated resource by about 20 percent. This represents the reject brine stream. The brine should not be returned to the sewer, as this would impact the wastewater quality for further reclamation. If developed, the well discharge would connect to the proposed 20-inch recycled water line in Cannon Road. Estimated capital costs for the well, pipeline, and sealing of the existing wells is $227,000. The cost of the demineralization unit would add another $1,287.000 in capital costs and $54,000 in annual operations and maintenance costs, including power. The equivalent cost ofwater, including annual capital cost, operations and maintenance, and power is estimated at $80 per AF without demineralization. This increases to $647 per AF with demineralization. 21 J:W3M01 \Mstmlan.wcd - 4.8 Hydro Generation Facility A water power generator is located at the Maerkle Reservoir site. The facility is not owned by CMWD and was constructed on site by the builder as a demonstration project. CMWD's operating provisions require at least 2.0 cfs of flow from the dam in order for CMWD to receive some of the power generated. 4.9 Disinfection Facilities There are two chlorine disinfection stations that operate within the District, the Maerkle Chlorination Station and the Twin "D Chlorination Station. These stations operate under normal operating conditions and were constructed in 1994 and 1996 respectively. The Santa Fe I1 Reservoir site is set up with chlorine disinfection capabilities to be used in unusual cases when chlorine boosts are needed for the reservoir. These stations are equipped with emergency scrubbers for chlorine gas use. 22 J:V237\001 Wslrplan.wpd TABLE 8 PUMP STATION SUMMARY (3) 150 (1) 50 (1) 40 (2) 75 (2) 150 Pump Station 7,000 New Variable Speed 1200 1996 Variable Speed loo0 Constant Speed 1500 1996 Electric Motors 1700 1996 Constant Speed 1700 Maerkle Reservoir Pump Station Ellery Pump Station Calavera Hills Pump Station Buena Vista Pump Station I co(nnent POW? 450 KW Generator No Back-up will not operate until Maerkle Reservoir lining and cover are completed; controlled by rotometerslcontrollers, two (2) 7.5 HP solution pumps and one (1) 1-114 HP mixing pumps are in building. Emergency only pumps from 330 HGL to 446 HGL c zone. No Electricity. Emergency use only Must use Calavera Hills zone. Generator for power. pumps from 446 to 580 Emergency use only; pumps from 225 zone to 330 zone from an emergency 10,000 gallon storage reservoir pumps have to be manually ad MuniciDal Water District Table IO Carls Wate PRV Master Ptan ummary Table Sefiing (psi) Service Zone 680 Name II Comments 1 I PRVPSV 105 + PRV/PSV. 52 60 - 8 1 680 510 318 La costa/south Coastal I 550 Ayres PRV PRV/PSV + 175 120 - 14 I 490 446 I 375 318 La CostaSouth Coastal Inactive Blackrail PRV ll pRv PRVPSV 4- PRVffSV 65 "1 318 La CosWSouth Coastal - 38 H Buena vista PRV 225 255 Cannon PRV Ilr 50 8 I 375 PRVPSV PRV/PSV Fire Flow 72 40 - 446 11 Clearview McArthur Fire Flow 330 20 I PRVPSV 79 58o(La Costa1 98 81 - +- 446 430 lnactve and Ininallon Onlv PRVPSV PRV/PSV Primary Fire Flow 375 330 25 I FireFlow 46 33 I PRVlFC 66 I 510 primly 318 La CostalSouth Coastal 510 El Fuefte PRV 11 El Fuerte and Bolero PRV 34 I PRVPSV 47 10 I 680 Primary Elm Reservoir South PRV I 45 - 95 245 490 PSV/Flow 11 Elm PSV Normally Closed Normally Closed Encinas PRV ll PRV/PSV 4-L 92 8 I 318La 255 CostalSouth Coastal - 145 Grosse PRV 418 46 I PRV/PSV 90 430 100 90 - 330 255 Jackspar PRV 11 Kelly PRV PRVlPSV 11 La Costa Hi PRV 50 I PRV 1 CWA3 700 La Costa Lo PRV ll - 52 I pRv/psv Tank l2 I 510 Not Running 318 La CostaSouth Coastal 580 (La Costa) 11 LaGolondrina 1:)223MOl\MISC6.ARM 55 I PRV/PSV 97 6 I 680 .- -~ CWA# - County Water Authority Connection Number: PRVPSV - Combination PRV and PSV Dam - Maerkle (195 MGI Dam .. 1 U23MOlWISC6 ARM 7 Chapter 5 Water Quality 1 5.1 Background The goal of the Carlsbad Municipal Water District (CMWD) is to provide a high quality drinking water for its customers. The CMWD receives its entire treated water supply from the Metropolitan Water District (MWD) of Southern California. Therefore, the quality of the CMWs water supply depends largely on the treatment practiced by MWD. The District provides quality control through the periodic addition of chlorine. The District pursues a vigorous program of water sampling to aid in quality control. In 1995, the District collected over 1,700 bacteriological samples from 33 sampling stations. The purpose of this chapter is to describe the CMWs water quality as it relates to current and proposed regulations. This discussion of water quality focuses on the existing supply source. This source is a combination of Colorado River and California State Project water which is treated at the MWD Skinner Filtration Plant. Many of the existing and pending regulations have a larger impact on the MWD operation as well as the wholesale cost which the District pays. Each of these regulations would have an additional effect on any District attempt to develop an alternative drinking water supply source. Existing Regulatory Requirements The modern day drinking water regulatory environment began with the passage of the Safe Drinking Water Act (SDWA) of 1974. This Act initiated national drinking water standards for 32 contaminants and a FederallState oversight program. The Act dramatically changed the manner in which water was regulated because of the widespread powers given to the US. Environmental Protection Agency (USEPA). - The SDWA was amended in 1986 and, again, the amount of regulation associated with drinking water was dramatically increased. Many of the recently-proposed regulations originate from mandated requirements of these amendments. At the core of the amendments is the requirement for the USEPA to set standards for 83 contaminants specifically listed in the Act and to increase this number by 25 contaminants every three years. Hence, the total number of regulated contaminants is scheduled to forever increase in the future. This particular provision has come under increased review as it would perpetually increase the cost of drinking water and would cause undue hardships on small suppliers. Further increase in the number of regulated contaminants is on hold pending SDWA reauthorization. Standard Settinq The current method of developing drinking water regulations was well-defined in the 1986 amendments. A risk assessment is performed on each containment where the hazard is identified, the impact of varying dose on the response to a contaminant is determined. and the exposure assessed. This risk is characterized by explaining the underlying assumptions and uncertainties associated with the evaluation. This type of approach is best suited for chemical contaminants and may not be applicable to microbiological contaminants because of the increased difficulty in measuring their presence in water and the fact that there can be highly sensitive subpopulations. Once the risk has been quantified. a maximum contaminant level, or MCL. is assigned. The MCL is not to be exceeded in any finished water sample. However, there are provisions for variances and 23 J:U23NM1 \Mstrplan.wpd - exemptions available to suppliers who can demonstrate that there is no economical method to Comply with an MCL and no alternative water source. A public notification process for systems that violate the MCLs is the enforcement mechanism behind these standards. The contaminants addressed by these standards include inorganic species, synthetic and volatile organic compounds, and radiological species. The inorganic species encompass natural contaminants such as arsenic and fluoride, and heavy metals that could originate from human activity. The organic compounds generally result from agricultural and industrial activities. /mpacts of the 1996 Amendments The 1996 Safe Drinking Water Act (SDWA) Amendments were signed into law on August 6, 1996. These amendments were developed with considerable participation by representatives of water utilities and state regulatory agencies. The general thrust of these amendments was to allow the Environmental Protection Agency (EPA) to focus on key standard development with a view to the best possible scientific foundation as well as consideration of the costlbenefit impact of each new standard. Key elements of the amendments which could impact the District include the following: 0 EPA is to publish a list of contaminants for possible regulation. This list is to be updated every five years; at each updating at least five contarninants must reviewed for standard setting (including the option of setting no standard). All new regulations must be based on the best available, peer-reviewed science and data from the best available methods. If the standard does not provide benefits which justiw the compliance costs, EPA may be allowed to set a standard based on a justifiable cost. The development of DisinfectanVDisinfection By-products and Enhanced Surface Water Treatment Rules are to continue as rapidly as possible. Rules for radon, sulfate, arsenic and groundwater disinfection are delayed. Federal funds will be made available to finance state revolving funds to aid water systems. - 0 0 0 0 Many provisions of the new amendments cover actions already taken by the District, such as producing annual water quality reports for consumers. or requirements already in place at the State level, such as watershed protection. 5.2 Specific Requirements In addition to the standard setting described above, the Safe Drinking Water Act and its amendments also stipulated that a number of other health concerns ultimately be addressed by the EPA. Over the last 20 years, and especially during the last five years, there have been a number of rules and regulations that have impacted the District. The most significant rules are summariied in this section of the Report. Trihalomethanes The first disinfection by-product regulation was promulgated by the EPA in 1979. The total trihalomethane rule set a maximum contaminant level (MCL) of 0.100 milligrams per liter (mglL) for the sum of the four trihalomethanes including chloroform, bromodichloromethane. dibromochloromethane and bromoform. This regulation pertained to systems serving a population of greater than 10,000 using at least some surface water. This regulation was significant in the following regards: 24 J:u23Aoo1 \Mslrplan.wpd - 0 A family of contaminants was regulated instead of a single species. This assumes that all species in the family have the same health risks, which subsequently has been shown to be incorrect. However, this approach is reasonable before sufficient information is available to assess the risks of each species. A one-year running quarterly average approach to the MCL was established. That is, the results from the last four quarters are averaged with each new sample or set of samples. This method allows for the seasonal vacations that may impact a parameter such as TTHMs. where it has been shown that generation is a relatively strong function of temperature. Samples are collected within thedistribution system instead of atthe point-of-entty to thesystem. This produces a better reflection of the water quality that is delivered to the customers. 0 This regulation has had a significant impact on areas of the country where THM precursor concentrations within a source water are high enough where significant amounts of THMs were being generated in the distribution system with continued exposure to free chlorine. One of the most cost-effective methods to address this has been to switch to chloramines within the distribution system, as MWD has done, to quench the further formation of THMs after primary disinfection has been realized in the treatment plant. This regulation will be superseded by the proposed DisinfectantlDisinfection By-product Rule that will lower the MCL for TTHMs. This proposed regulation is described in a subsequent section of this Chapter. Compliance The District takes six TTHM samples each quarter from six separate sites. The average TTHMs ranged from 0.037 to 0.064 mg/L in 1995. The chloramination strategy implement by MWD at the Skinner WTP has been effective in keeping TTHM concentrations well below the 0.1 mg/L standard. Total Coliform Rule (TCR) The TCR was promulgated by the EPA on June 29,1989, and became effective on December 31,1990. Under this rule, the maximum contaminant level goal for total coliform bacteria is zero. Accordingly, compliance with the rule is based on the presence or absence of total coliforms. For public water systems collecting at least 40 samples per month, no more than five percent of the monthly samples may be total coliform positive. The TCR prescribes specific monitoring requirements based upon an established "sample siting" plan. The intent of the sample siting plan is to provide for routine monitoring throughout the distribution system, and in particular those areas which are prone to long residence times and/or slow turnover. Also included in the rule are requirements for "secondary" disinfectant residual within the distribution system. The secondary disinfection requirements are the same as prescribed in the Surface Water Treatment Rule. 7 As noted above, the District will use chloramines for secondary disinfection in part because of its characteristic stability and long life. Continued use of chloramines is therefore considered a prudent strategy for compliance with the TCR. 25 J:\223A001\Mstrplan.~pd ,- Compliance The District currently performs a minimum of 128 total coliform tests each month. Additional coliform tests are periodically needed for retesting sample locations where a positive coliform result was obtained. The percentage of positive samples has been less than the five percent regulatory requirement every month and is most always less than 0.5 percent. Lead and Copper Rule (LCR) Treated water is characteristically unstable as the result of addition of acidic materials such as alum and chlorine. This instability can leach lead and copper from the plumbing in consumers' houses, which could result in accedence of this rule's action levels. The LCR was promulgated by the EPA on June 7, 1991, and became effective for large water systems like the District (serving greater than 50,000 people) on January 1, 1992. The rule establishes monitoring requirements and "action level" concentrations for lead and copper; action levels are 0.015 rng/L and 1.3 mglL for lead and copper, respectively. Under provisions of the LCR. water suppliers are required to monitor distribution system water quality for lead and copper. Water systems exceeding the "action levels" for lead or copper are required to evaluate treatment alternatives to reduce the concentrations of these constituents in the distribution system. Compliance The District has been very successful at complying with the requirements of the LCR. All distribution system samples were analyzed and determined to be under the regulatory limits during two six-month intervals. The EPA indicated that no further sampling was required under the LCR. Surface Water Treatment Rule (SWTR) 7 The SWR was promulgated by the Environmental Protection Agency (EPA) on June 29, 1989, and became effective on December 31, 1990. For systems using surface water sources for supply, the SWR requires that treatment be provided to reduce turbidity and the microorganisms Giardia, Leaionella. viruses, and heterotrophic plate count bacteria (HPC). Specifically, the SWTR establishes treatment and performance standards to provide a minimum reduction of 99.9 percent (3-log) for Giardia cysts, and 99.99 (4-log) for viruses. The overall reduction of Giardia and viruses is to be achieved via a combination of physical removal by pretreatment and filtration. and inactivation by disinfection. Reauirements Filtration: The SWR outlines filtration performance requirements as a surrogate measure of the removal of Giardia cysts and viruses. Filtration performance is measured via effluent turbidity. which is not to exceed 0.5 NTU in more than five percent of samples collected in any single month. Primary Disinfection: The remainder of the overall 3-log Giardia cyst and 4-log virus treatment requirement is to be provided by inactivation via disinfection. The SWR requires that well+perated conventional treatment plants like MWD's Skinner WTP provide primary disinfection to achieve a minimum of 0.5-log Giardia cyst and 2-log virus inactivation. I Compliance with the primary disinfection requirement must be demonstrated by meeting minimum "CT requirements, where C is the residual disinfectant concentration in mg/L at a point before or at the first customer, and T is the effective contact time with the disinfectant. The ability to meet minimum "CT requirements is a function of the actual detention time through the plant, water temperature and pH, required log removal (Giardia or virus), disinfectant type (i.e.. chlorine, chloramines, ozone) and disinfectant residual concentration. Secondary Disinfection: In addition to primary disinfection requirements, the SWTR also requires protection against microbial contamination in the distribution system. Specifically, the SWTR outlines distribution system disinfection requirements ("secondary" disinfection) to inactivate microbiological pathogens including Leaionella and HPC bacteria. Under the rule measurable disinfectant residual must be maintained in the distribution system, or alternatively, HPC levels must be less than 500 colonies/mL, in at least 95 percent of the samples from the distribution system each month, for any two consecutive months. A measurable distribution system disinfectant level is defined as 0.2 mg/L for free chlorine and 0.5 mg/L for chloramines. The distribution system sampling requirements are identical to those described for the Total Coliform Rule. MWD Compliance The treatment operations performed by MWD at the Skinner Filtration Plant comply with both the filtration and primary disinfection requirements of the SWTR. The District is responsible for secondary disinfectant concentrations and sampling within the distribution system. - Secondary Disinfection: Secondary disinfection for the District's distribution system is provided by chloramines, a combined chlorine residual formed via the addition of both chlorine and ammonia which are added at the Skinner Filtration Plant. Chloramines are used for secondary disinfection because they provide a more stable, longer-lived residual than free chlorine, which is essential for some areas of the distribution system with long residence times. Perhaps more importantly, chloramines also are advantageous from the standpoint that few disinfection by-products are formed in the distribution system. The District takes about 264 samples per month in the distribution system. Sample concentrations rarely fall below the 0.5 mg/L requirement for combined chlorine. Hence, the District is complying with these requirements. Sfate of California Drinking Wafer Regulafions General State of California drinking water rules are compiled in Title 22 of the California Code of Regulations. In terms of standards and treatment rules the State of California Department of Health Services (CDHS) has adopted Federal regulations Fluoridation California Law AB 733 requires public water systems with at least 10,000 service connections to fluoridate their water supplies. This requirement was contingent upon CDHS providing funding for such 77 5:\2237\001 \Mstmlan.wod - a system. California water utilities were required to submit a cost estimate for their facilities so that CDHS could arrange a priority listing for the utilities. The District submitted its total capital cost estimate to the CDHS by the required date of July 1, 1996. 5.3 Anticipated Future Regulatory Requirements New drinking water regulations which were mandated by the 1986 Amendments continue to be developed even with the passage of the 1996 Amendments. The two key rules in this category are the DisinfectantlDisinfection By-product (DlDBP) Rule and the Enhanced Surface Water Treatment Rule (ESWTR). Although these rules are still in development some draft materials have been generated. These anticipated requirements are summarized in the following sections. In terms of current operations the DlDBP Rule and the ESWTR will have a greater direct impact on the District's wholesale supplier, MWD, than on the District. These impacts will ultimately have both a cost and a distribution water quality effect on the District. Changes in MWD operations are discussed later in this section. The original 1986 impacts also directed the Environmental Protection Agency to draft a series of additional water quality rules. The 1996 amendments have addressed the delivery schedule for rules such as the Arsenic Rule and the Groundwater Treatment Rule. These rules would have a potential impact on the development of alternative water supplies for the District. Disinfectant/Disinfection By-Products Rule (D/DBP) The DlDBP rule was proposed on July 29,1994. The proposed DlDBP Rule addresses several complex and interrelated issues. The intent of the rule is to balance the risk of microbial disease outbreaks against the risks 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. /- Currently, the only disinfection by-products regulated are total trihalomethanes (TTHMs). The existing drinking waterstandardforlTHMsof0.10mg/Lonlyapplies tosystemsserving over 10.000peopleand was discussed earlier in this Chapter. The DlDBP 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 following 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 II requirements. Proposed new drinking water standards under the DlDBP Rule are shown in Table 5.1 28 J:U23Mo1 \Mstrplan.wpd Chloroform Bromodichloromethane Bromoform Bromate Dichloroacetic acid Trichloroacetic acid Chlorite Dibromochloromethane Chloral hydrate 'reposed Stqe I Maximum Contaminant Levels fWsb IT@&) Total trihalomethanes (TTHMs) Total haloacetic acids (THAAs) Bromate Chlorite Jot all compounds with MCLGs will have an MCL established lTHMs THAAs Chlorine Chloramines Chlorine dioxide the 0R)BP Rule 0 0 0 0 0.10 0.3 0.06 0.005 0 0.080 0.060 0.010 1.0 0.040 0.030 4.0 4.0 as total chlorine 0.8 The term"maximum contaminant level goal", or MCLG. refers to a desired maximum concentration that is calculated by a prescribed EPA method based on health effects. These goals are nonbinding 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 term "contaminanr' obviously does not apply to chlorine, chloramines or chlorine dioxide, which are the three disinfectants slated for limitation under the DlDBP Rule. The MRDL requirements are similar to the MCL requirements and the District must achieve an annual running average, which is computed quarterly, less than the MRDL value. Stage I requirements of the D/DBP Rule was initially scheduled to be effective for systems serving greater than 100,000 people in June 1998. however, implementation will most likely be delayed much as the ICR has been delayed. The second stage requirements were originally scheduled for promulgation in the year 2000, but this will likely be delayed at least one year since the results from the ICR will not be available as originally scheduled. 29 F Trihalomethanes and Haloacetic Acids As proposed, the rule attempts to reduce the risks from D/DBPs by creating new drinking water standards. In a first stage, the Rule will set a new MCL for TTHMs at 0.080 mglL and an MCL for the total of five haloacetic acids (THAAs) of 0.060 mg/L. The five HAAs include monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid. Compliance with the new MCCs will be based on a running annual average of quarterly samples. Chlorite The proposed Stage I chlorite MCL is 1.0 mglL. Only systems using chlorine dioxide will be required to collect distribution samples for chlorite. This requirement is therefore not expected to impact the District. Bromate Bromate is formed during oxidation, with ozone or chlorine, of water supplies containing bromide. Of systems treating high bromide source waters, bromate formation is greater for systems using ozone as opposed to chlorine. Chlorine and Chloramines Under the proposed rule, the District will also be required to monitor for disinfectant level in the distribution system. Distribution system residual monitoring requirements will coincide with similar requirements of TCR and SWR. Compliance with the maximum disinfectant residual levels (MRDLs) will be based on a running annual average, computed quarterly. As shown in Table 5.1, the proposed MRDL for chloramines, the District's distribution system disinfectant type, is 4.0 mglL. The District's residual concentrations are controlled to be in the range of 1.5 to 2.0 mglL so compliance is already being achieved. Chlorine Dioxide Only systems using chlorine dioxide will be required to monitor for chlorine dioxide residual. This requirement is therefore not expected to impact the District. Total Oraanic Carbon FOCL Stage I of the proposed rule will also include a treatment technique requirement for removing DBP precursors. The objective of this requirement is to limit the formation of both known and unknown DEPs. The treatment technique requirements are also known as the enhanced coagulation requirements of the DlDBP Rule, although the latter form can be misleading since other methods besides enhanced coagulation can be used to satisfy these requirements. The term treatment technique will be used in this Report. 30 J:U237u)Ol \Mstrplan.wpd _- Total organic carbon (TOC) is a measure of the organic material in water. It is analytically determined by initially purging the sample ofall soluble carbon dioxide. Then, all of the organic materials is digested and measuring the amount of carbon dioxide gas produced. The amount of inorganic carbon, involved in soluble species such as carbonate and bicarbonate ions, must be subtracted from the total amount of carbon dioxide produced. Since DBPs must be formed from organic material and the TOC analysis is relatively simple and inexpensive to perform, TOC is proposed to be used as a surrogate measurement of DBP precursors.. The level of TOC removal required will be based on the source water alkalinity and initial TOC concentration as shown in Table 5.2. If these limits cannot be met, the system will be allowed to conduct bench-scale tests to determine an alternative site-specific limit. 22-4 >4-8 >8 40% 30% 20% 45% 35% 25% 50% 40% 30% Treated water TOC less than 2.0 mglL prior to addition of chlorine as primary disinfectant. Source water TOC less than 4.0 mglL, alkalinity greater than 60 mg/L, TTHMs less than 0.040 mglL, and HAAS less than 0.030 mg/L (using any disinfectant). lTHMs less than 0.040 mglL and HAA5 less than 0.030 mglL when chlorine is used as the primary and secondary disinfectant. Long-Term D/DBP Rule Stage II of the DlDBP rule proposes to further reduce drinking water standards, or MCLs, for D/DBPs. New DlDBP standards will be proposed under Stage II if it is determined that treatment techniques such as enhanced coagulation, 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 II rule. As currently proposed, the MCLs for TTHMs and THAAs would be reduced to 0.040 mglL and 0.030 mglL, respectively. Enhanced Surface Water Treatment Rule (ESWTR) Since 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 poorquality source water. The ESWTR was proposed simultaneously with the DlDBP Rule in July 1994. The proposed version was termed "interim" and includes provisions to be modified based on the results from the ICR microbiological data. The interim rule applies only to systems serving 10,000 people or more. The possible options that could be promulgated in the final ESWTR include increased removal requirements for Giardia and viruses than currently required by the SWTR and making no changes to the SWTR. A long-term ESWTR will be developed for systems serving less than 10,000 people and may include revisions to the interim ESWTR for larger systems. The ESWTR will likely set a maximum contaminant level goal for Cryptosporidium of zero. A sanitary survey of the source and surrounding watershed would be required every five years to establish baseline source water quality parameters. Based on the results of the survey. and water quality information developed under the ICR. the overall treatment requirements of the existing SWTR could be increased. For example, a 3- to 6-log removal of Cryptosporidium (or Giardia) may be required based on site specific source water cyst concentration. The EPA is considering several treatment options to address Cryptosporidium removal. One strategy is to optimize treatment based on a reduced turbidity performance standard of 0.20 NTU. ,--- 5.4 Additional Rules Arsenic Rule An MCL of 0.05 mg/L of arsenic has been in place for almost 20 years. EPA was considering lowering this standard to between 0.002 and 0.02 mglL based on health effects data. The current arsenic level in the District's supply is at the lower end of this scale: 0.002 mglL. However, the 1996 Amendments have delayed proposal of an Arsenic Rule until January 1, 2000. The EPA is currently studying ways to reduce arsenic health risk uncertainties. Groundwater Disinfection Rule The 1996 Amendments have delayed the proposal of the Groundwater Disinfection Rule until at least 1999. This rule will include guidance on which systems are required to provide disinfection. EPA will be required to establish this requirement based on a cost-benefit analysis. 5.5 District Water Quality Sampling Points .- The District has 26 standard sample points in the distribution system including one point which is out of service. There are eight routine sample points. One of these points is out of service. The system sample points are listed in Table 5.3. 32 J:\2237\001 \Mslrolan.wod ,-- I IA) "C" Reservoir 0 18G) Madonna Hill R 28) 2770 Tamarack I R I 19H) 2924 College Is ~ 3C) T.A.P. HllLO 48) 2728 Athens 58) 2764 Southampton R 201) 2532 La Golondrina R R 215) 2700 Cazadero R R 22J) 721 1 El Fuerte S 68) 4210 Trieste 78) 2408 Sonoro Ct. * in place of 148 ED) 2800 Ave. de Luisa I R I 25K) La Costa Avenue IR R 23K) 7300 Almaden R R 24K) La Costa Fire Station S 9E) Sears 1 OE) 2443 Tuttle 11 E) 3090 Jefferson R 26K) 7166 Tern R R 27L) Poinsettia R R 28L) Camino de las Ondas R 148) 2161 Janis Way I 0 I 31E) 5232 Los Robles Is 12E) 3960 Garfield 15F) 4000 Park I R I 32E) 1799 Palomar Oaks IR S 29K) Lakeshore Garden R 13F) 3355 Monroe Notes: 0 = Out of Service R = Routine S = Special S I 30K) 6550 Ponto Is Water Quality 16E) 4823 Neblina 178) 1832 Palisades Table 5.4 compares District water quality with Federal drinking water standards. This data indicates that current water quality is well within all primary and secondary standards with the exception of total dissolved solids (TDS). The Federal secondary standard of 500 mglL is lower than the District average of 601 mglL. This situation is shared by users of Colorado River water in the Southwest. R 33H) 1979 Palomar Oaks R R 34H) Point "D" R 33 Parameter Fed MCL PRIMARY STANDARDS Combined Filter Effluent Turbidity (NTU) Microbioloaical Total Coliforn Orqanic Chemicals (malL) Total Trihalomethanes lnoraanic Chemicals (rnalL) Arsenic Barium Fluoride Nickel Nitrate (as N) Nitrate plus Nitrite (as N) Selenium Faltrabon Plant EfRmts (Average) 0.5 (b) 5.0% 0.10 0.05 2 4.0 0.1 10 10 0.05 0.07 0.14% 0.042 0.0022 0.125 0.22 0.006 0.17 0.17 0.002 SECONDARY STANDARDS Chloride (mgn) 250 90 Color (units) 15 2 Corrosivity nonarrosive - Odor Threshold (units) 3 -- pH (units) 6.5-8.5 8.07 Specific Conductance (jmho.cm) NS 978 Sulfate (mglL) 250 (‘500) 242 Total Dissolved Solids (mg/L) 500 601 Turbidity (NTU) NS 0.07 Note: Based on CMWD 1995 Annual Water Quality Report 34 J:\2237\001 Wlstrplan.wpd - Disinfectant Residual The District monitors the chloramine residual at the sample points listed in Table 5.3. The residual typically ranges between 0.5 and 1.5 mglL. The lower residuals generally occur in areas of low water demand where the system dead ends. Nitrification is a common problem among utilities receiving MWD water in San Diego County. Nitrification is a chemical process in which free ammonia is converted to nitrate and nitrite by ammonia-oxidizing bacteria. This process can cause a rapid depletion in the existing residual. Nitrification is a common practice among utilities in warmer climates which utilize the chloramines. Factors behind nitrification include high water temperatures (>20°C). long detention times and availability of ammonia. Control measures include raising the chlorine: ammonia ratio at the feed point, increasing the overall chloramine dosage, periodic free chlorination and system flushing. MWD has incorporated each ofthe first three steps into its normal operating procedures. The District has also taken nitrification control steps. The installation of the new 8.5 million gallon Twin "D Reservoir was accompanied by nitrification problems due to the higher detention time as compared to the replaced 1.25 million gallon reservoir. District staff was able to combat the nitrification by adding sufficient free chlorine at the reservoir inlet to consume the available ammonia. 5.6 MWD Operations The quality of the water in the District's system is largely determined by the raw water quality and the treatment process at MWD's Skinner Filtration Plant. There is a possibility that these parameters will change in the coming years. Ozonation During the late 1980's the MWD committed to a course of installing ozonation equipment at two of its water treatment plants: the Jensen and Mills plants. The ozonation process was intended to meet the requirements of the DlDBP Rule. Although the DlDBP Rule has been delayed, MWD is continuing to develop these facilities. Ozonation was intended to be installed at the remaining three plants, including the Skinner Filtration Plant, between 2005 to 2010. The revised schedule for this installation is uncertain. The process of ozonation may cause changes in the distribution system quality. In general, the process can increase the amount of assimable organic content in the treated water. This may lead to a higher microbial regrowth potential in the system. MWD's ongoing research program is looking at approaches such as biologically activated filters. Colorado River/State Project Water Split The MWD plants treat a mixture of Colorado River and California State Projectwater. The Skinner VVTP has traditionally processed a higher percentage of Colorado River water. This water is relatively high in TDS; thus the users downstream from the Skinner Plant typically receive a higher TDS concentration. Some of these users have requested that MWD increase the percentage of Colorado River water at the Skinner facility to lower the TDS in the product water. However, the State Project water has a higher organic content than the Colorado River water. Thus, a higher percentage use of State Project water at the Skinner Plant in the future may result in both a lower TDS content and a higher bacterial regrowth potential in the District distribution system. 35 J:U23M01 Vulstmlan.wod - Chapter 6 System Ulodellna I 6.1 Modeling Criteria The H20NET computer program was used to simulate the water distribution system. The program allowed many different water distribution scenarios to be tested, many were emergency simulations such as closure of a major transmission main, fire flows, and other tests concerning projected future demands. The computer program was tested and calibrated to the actual water distribution system to ensure that the model yielded accurate results. The final HZONET model of CMWD's system program has been provided to the CMWD. Friction Factors (Hazen Williams C" Coefficients) The primary function of the Hazen Williams "C coefficient is to estimate system friction losses. WWout specific testing of the pipelines, the "C coefficient is only an estimate. Two particularly useful trends of "C factors are that the "C factor declines with pipe age and that for a given pipe age, a corrosive material pipeline will have a lower "C coefficient than a non-corrosive material pipeline. In general, older pipelines and/or corrosive material pipelines are particularly susceptible to a wider range of actual "C values. In this study, a corrosive material pipeline is defined by the lining of the pipeline. Pipeline materials considered corrosive are: unlined cast iron, unlined ductile iron, and unlined steel. These pipes were assumed unlined if installed before 1950 or if othewise known. Noncorrosive material pipelines include: PVC. A.C., cement mortar lined cast iron, ductile iron, and steel. A secondary function of coefficients is as a tool to rank the pipelines most likely in need of repair. Because the "C coefficient allows for both the age and susceptibility to corrosion, the lowest "C coefficient pipes may be a higher priority for replacement than another equivalent pipeline with a higher "C coefficient. Figure 9 shows the Hazen Williams "C coefficients versus pipe age in this report. The curve shown in the figure, shows the "C coefficient for both the pipe material and its. Note that if a "C coefficient were attempting solely to estimate friction losses and not prioritizing, a higher increment (e.g., increments of ten such as 80, 90, 100, etc.) would be more appropriate because a higher increment would more closely resemble actual conditions measured in the field. Storage For the CMWD system, the required storage volumes were calculated as the sum of operational, fire and reserve demands. Each demand category is described as follows: OPERATIONAL DEMANDS. Operational storage is the amount of storage required to accommodate demands above maximum day demands. Hourly peaking factors for the maximum day were used to create a graph of the demand for each hour on the maximum day. The operational storage required is the volume above the maximum day average flow rate. Figure 8 shows this diurnal curve for the CMWD system. The existing operational requirements can be seen graphically in Figure 10. FIRE DEMANDS. Fire storage is equal to the volume of water required for the largest fire flow requirement within the pressure zone. When one pressure zone extends over a large area, fire storage may be 36 .1.\77'17\nni\~~t~i~~ -d - recommended in two or more locations. The largest fire flow for each land use within the pressure zone was used for this analysis. RESERVE DEMANDS. Reserve storage provides water during emergencies such as pipeline failures, pumping or equipment failures, electrical power failures, and natural disasters. This report used 100 percent of the maximum day demand for reserve storage. 6.2 Hydraulic Analysis Base System Hydraulic analyses were performed by computer simulation using the water distribution modeling software, H20NET, which is run within the AutoCAD for Wtndows environment. It combines hydraulic and water quality modules based on EPANET and outputs into CAD geographic information system (GIs), and word processing outputs. The analysis engine of the program solves the hydraulic model by using the "Gradient Algorithm Hybrid Method" developed by EPANET. This method solves a system of linear equations in an iterative process using matrix techniques. There are many ways to evaluate the results, one being the data query function which enables various parameters to be evaluated, according to specific criteria, such as flowrate, headloss and velocity. Testing and Calibration In order to verify that the model sufficiently simulates thewater system, field fire hydrant flow testing was performed. Similar flow conditions were then imposed on the model and the model results were compared to the field test results. Approximately 18 field calibration testswere conducted forthis model. - Field flow tests were broken down into two categories, static and dynamic. Field personnel first took a static pressure reading at the desired fire hydrant. Simultaneously. other field personnel recorded data on pertinent facilities (reservoir water levels, booster pump status, flow and pressure, etc.). The field crew would then open the fire hydrant and take a pitot tube reading in order to determine flow, and a residual pressure reading at a nearby hose bib. As in the static test, other field crew simultaneously recorded data on pertinent facilities. All flows are then converted to flows available with a 20 psi residual pressure as stipulated by fire flow requirements. Model Calibration Final calibration shows that the model accurately simulates the water distribution system. Table 11 provides a summaiy of the final calibration results. The model results with flows much higher than the field test indicate a strong system. The model calibration results show that most differences between field and model results for static and residual pressures vaned only by a few psi. The only exception was flow test no. 8 (550 Pressure Zone) where the model results were higher for both the residual and static pressure; however, the flow was the same. 77 - Results The model was used to simulate different water distribution scenarios which could not be practically performed on the actual system. Those scenarios included: Average Day Demands (6,370 gpm) Maximum Day Demands (10,192 gpm) Peak Hour Demands (20.384 gpm) Maximum Day Demands with Fire Flow After the simulation of each of the above scenarios, the model output data was analyzed. The results are as follows: Averaae Dav Demands The average day demand scenario was run as a baseline so that other scenarios could be compared to "typical" operations. Maximum Dav Demands The maximum day demand scenario was used to examine pipeline velocities. headloss, and pressures. Also, the maximum day demand was used as a base to create other scenarios. Peak Hour Demands - The peak hour demand scenario was also used to examine pipeline velocities. headloss, and pressures. Maximum Dav Demands with Fire Flow This scenario provides a good indication as to the adequacy of the water main distribution system. There are numerous areas which cannot provide the amount of fire flow required in Table 5. Fire flow contours were made for available fire flows (at 20 psi residual) within the distribution system during maximum day demands. The fire flow contour map indicated the significant areas which cannot provide the required fire flow. A majority of the deficiencies are due to excessive headloss. The notable deficient areas include the north village area and the surrounding pressure zones and the westerly portion of the distribution system. Refer to Chapter 7, Capital Improvement Plan and Figure 11 for further discussion. The transmission mains are adequate for the existing system. Improvements for the ultimate system are mainly transmission mains to serve future development. Many ofthese pipelines are in future roads and extensions of existing roads. J:V237WO1 \Mstrplan.wpd I Water District 5 6 7 8 446 48 40 988 48 44 ~ ~ 285 64 47 666 64 47 670 225 89 86 1,229 91 89 1,229 700 125 125 942 126 125 942 550 107 94 1,201 112 101 1,207 31 349 I 60 I 48 I 788 I 60 I 49 I 10 11 12 II 4 I 330 I 67 I 64 1 1.145 I 66 I 641 1,16911 490 NA 94 1,054 98 97 1,054 375 76 74 1,154 79 77 1,167 375 87 85 1.173 88 85 1,178 16 17 18 19 II 9 I 550 1 128 I 118 1 1.374 I 129 I 112 I 1.37411 ~ ~ ~ 510 125 110 1,229 128 111 1,231 31 8 123 120 1,349 129 122 1,349 318 78 75 1,135 81 76 1,135 225 100 97 1,316 102 99 1,326 - 13 I 255 I 89 I 841 966 I 89 I 85 I 970 n 15 I 580 I 841 49 I 1.110 I 85 I 52 I 1.12411 J U23MOIWlSClO.ARM LII P v) > Z Y I 0 0 VI v- 0 8 02 0 0 0 v, v- 2 ... 3 ... Q1 5 .- VI 2 L 0 U t 4 11311 SWVllllM N3ZVH rn ru 3 0 suop3 jo spuvsnoqJ aNvwia - Chapter 7 Capital impravement I To aid the CMWD in budgeting for capital improvements. this section provides estimated costs for reservoirs, transmission and distribution pipelines, pumping stations and miscellaneous improvements. This 1996-1997 CIP (Fiscal Year 1997) will be based on this Master Plan, so will differ from previous ClPs in earlier Master Plans. 7.1 Storage Requirements Existing Storage Requirements Existing system requirements were broken down by source connection and analyzed by pressure zone within the areas source of supply. The Palomar Airport Road and South Aqueduct Connection supply sources were analyzed as one group. For the existing average daily demand, some individual pressure zones have a deficit of storage but only one connection source. The TAP connection, has an overall deficit of storage. This is due to the fact that the 580 Pressure Zone has no storage provisions and the only reservoir in the supply source area is the TAP reservoir (6.0 MG). This deficiency is currently met by the following: The 700 Pressure Zone can feed the entire system. The existing Calavera Pump Station can handle the 580 Pressure Zone fire flow requirement of 1500 GPM. /-- Ultimate Storage Requirements Ultimate storage requirements were calculated using the same procedure as the existing storage requirements. The future demand yields a deficit of 11.7 MG of operational storage. It is recommended that this deficit be met by constructing an 8.5 MG reservoir at the Twin "D" Reservoir Site (375 HGL) and 3.2 MG of storage in the 446 Pressure Zone. Tables 12 and 13 summarize existing and ultimate emergency storage requirements. 10-Day Emergency Storage Requirements The San Diego County Water Authority recommends a total storage equivalent to ten times the average day demand. For CMWD, the l0day storage requirement equals 125.7 MG for existing needs. Based on projected average day demands, the 10 day emergency storage requirement for ultimate conditions is 235.8 MG. In order to meet this requirement, it is recommended that the CMWD pursue the following option: Ultimate l0day emergency storage requirements of 195.0 MG can be met by Maerkle Dam with the remaining amount from either the proposed Mt. Israel [Olivenhain Municipal Water District (see Figure 2)] project or a new 41 MG reservoir adjacent to Maerkle Reservoir. The Mt. Israel Project would require constructing a 21-inch pipeline from the proposed Gaty Water Treatment Plant to the La Costa Hi Reservoir, a distance of 25,200 feet. 39 J:V237\001 \Mstrplan.wpd .- The Olivenhain Municipal Water District (OMWD) has been planning the Mount Israel storage project for over 10 years. The current planning is for a joint project between the OMWO and the SDCWA. A dam and reservoir will be constructed for the Authority's Emergency Storage Project as well as storage for OMWD. The reservoir is expected to store 24,000 acre-feet, with OMW owning between 3,600 to 4,600 acre feet per year of operational storage. This will provide OMWD with emergency storage for planned maintenance or disruption of the Authority supply. OMWD is also planning to wnstruct an 85 mgd membrane water treatment plant referred to as the "Gaty Water Treatment Planr'. It will be located near the planned dam with the site capable of an expansion to 125 mgd. The treated water will be piped west to the OMWD's distribution system. OMWD will be pumping all their water to Gaty Reservoir. Another option is to construct a separate gravity flow pipeline from the Gaty Water Treatment Plant to the La Costa Hi Reservoir. This project provides the CMWD an opportunity for increased reliability. CMWD would purchase raw water from the SDCWA year-round to be treated by OMWD by increasing the size of the treatment plant to accommodate CMWD. The treated water would need to be conveyed in shared pipelines to OMWD's Gaty Reservoir. From there, CMWD would construct a dedicated 21 -inch line to the CMWD's La Costa High Reservoir. The potential advantages to CMWO under this option, include access to emergency supplies in Mount Israel, a product water with reduced total dissolved solids, an additional water connection point to the system, and the potential for a less costly source of water. 7.2 Recommended Improvements Pipelines The water mains with the "A" designation listed in Table 15, Capital Improvement Program are recommended to improve the available fire flow. Where available fire flows were lower than required, improvement of older water mains, where possible were evaluated for replacement in order to increase available fire flow. Several of the recommended pipe projects are pipe replacements. Two of these projects are intended to replace older pipelines with either new steel pipelines or PVC pipe. The remaining of the improvements are to meet future demands. One example is the proposed 14-inch line in the future extension of Cannon road. This will aid in moving the water from the 375 Pressure Zone all the way to the 255 Pressure Zone. There are also proposed pipelines in future Aviara Parkway, future Poinsettia Lane, and extensions in El Fuerte and Cannon Road. Pump Stations There are two pump stations proposed, first is to upgrade the existing Calavera Pump Station. This will allow the 580 Pressure Zone to have extra storage via pumping from the proposed TAP Reservoir. The second, is a pump station to supply water from Maerkle Reservoir 490 Pressure Zone to the 700 Pressure Zone. This pump station is needed primarily for emergency requirements and during routine maintenance of the SDCWA aqueducts. 41) J'V237\001\Metrnlan wnd Reservoirs - An additional 8.5 MG "D Reservoir should be buiR adjacent to the exiting "D Reservoir. This reservoir is proposed to be constructed before the year 2005, when the southwest quadrant will be built out. A 3.0 MG Reservoir is proposed in the 446 Pressure Zone. This will help the 446 and 580 Pressure Zones to meet their ultimate storage requirements. An emergency storage of 41 MG is needed adjacent to Maerkle Reservoir to meet the 1Oday storage requirement. 7.3 Estimated Costs Basis of Costs Estimated costs were determined by multiplying a unit cost for construction by the estimated quantity and adding 35 percent for contingencies. engineering, and administration. The unit costs used for estimating were based on the Daily Construction Report and recent project experience (all figures include construction costs plus 35 percent). The probable costs are divided into three construction phases, as follows: Phase 1 (1997-2000). Phase 2 (2001-2005) and Phase 3 (2006 and beyond). Improvement phasing is based on (1) meeting the projected water demands, (2) development schedules provided by the City, and (3) projections of development and growth provided by the Planning Department. Phasing for recommended improvements may be accelerated or deferred as required to account for changes in development schedules, availability of land or rights-of-way for construction, funding limitations, and other local considerations that cannot be predicted at this time. All opinions of probable costs presented herein are based on 1996 dollars (Engineering News Record Construction Cost Index - 5727, November, 1996), and include an allowance of 35 percent for contingencies, engineering, legal, and administrative costs. Land costs are included where appropriate for storage facilities and pump station sites. No costs are included for land or right-of-way acquisition for transmission and distribution pipelines as they are typically constructed in public right-of-way. If land needs to be purchased for project, it is noted. - These phases will provide the CMWD with a long range planning tool and divides the improvements in an orderly manner to improve the system in order to keep up with growth. In order to determine the phase for an improvement a priority list must be established. The primary concern is always to provide a potable water supply for the health, safety, and welfare of the public and residents of CMWD; Therefore, the priority for existing systems are usually in the order of supply, storage and pumping. Supply improvements can be improved by adding storage at sites which can feed multiple zones, and connecting pressure zones. These improvements benefit the entire distribution system by meeting emergency conditions with multiple sources and improving rates of supply. The ultimate system's improvements should be prioritized by the same components as mentioned above while keeping up with added demands. All of the water main, pump station, and reservoir improvements are shown in Figure 11. 41 J:V237\001 \Mstrplan.wpd - Capital improvement Projects In order to plan forfuturewater system improvements, a phased capital improvement program has been developed in five year increments ending at the planning horizon year of 2015. The proposed improvements by phase are summarized in Table 14 and graphically depicted in Figure 11. A brief narrative summary for each of the improvement phases follows Capita/ lmpmvemenfs Phase 7 (7997-2000): A majoriiy of the pipeline improvement projects in this phase are recommended to improve fire flows District wide. The remaining pipeline improvements are to replace old steel pipe which due to age, are most likely improperly lined and protected and need replacing. Capita/ lmprovements Phase 2 (2007-2005): lmprovements for this phase consist primarily of adding 3.0 MG of storage at the existing TAP Reservoir site to provide additional storage to the pressure zones supplied by the TAP connection. This additional storage will also require pipeline improvements to convey the water to the surrounding areas. Also proposed is a pump station to convey water from the 446 pressure zone to the 700 Pressure Zone in emergencies. Capita/ lmprovements Phase 3 (2006-2070): Improvements recommended for this phase consist primarily of adding 8.5 MG of additional storage at the Twin "D" Reservoir site. The site already has a pad in place to accommodate the additional 8.5 MG reservoir, as recornmended by the previous Master Plan. This will require new water distribution mains as Summarized in Table 15. There will be no more improvements for the southwest quadrant of the District since this area will be built out by the year2005 The recommended improvements for this phase also includes a pipeline addition in order to bring 6.2 cfs (4.0 MG of 10day emergency supply) from Mt. Israel to the La Costa Hi Reservoir or a 41 MG reservoir adjacent to Maerkle Reservoir. - 42 5:\2237\001 \Mstrplan.wpd .- ~ Water Mains Reservoirs TAP (3 0 MG) Twin 'D' (8 5 MG) Mt lsraelemergency storage only 41 MG (Emergency Storage) TaMe 14 Carisbad Municipal Water OIstrict water Master Pian Capitat Improvement Summary $13.063.280 $1 1.148.070 515,350,640 f39.561.99C $2,430,000 S2.4M.WC $5,332,500 95.332.50( $20,500,000 UO.5W.00( Facility II Totals Phase 3 I Subtofal 11 I Phase 2 I (1997-2000) I (2001-2010) (2006 and beyong Phase 1 913,063,280 $19,113,070 536,850,640 $69,025,990 Pump Stations Upgrade Calavera Pump Station EmergencyMaintenance 700 Pressure Zone Pump Station 43 L I? X T c T- L L In _I T In 0 9 ? m 0 0 N N / - 5 €X/S7YNG STORAGE REQUIREMENTS PER PRESSURE ZONE 8.62 MDD 1.67 ADD = 12.57 MG IO Sw Rqx+ = 125.70 MG (.) =L)lbistqmrmp (+) =s~~~Olune MASTER PLAN DUSTING STORAGE REQUIREMENTS PER PRESSURE ZONE TABLE 12 .ASL Consulting Engineers CARLSBAD MUNICIPAL WATER DISTRICl UL77MA7E STORAGE REQUIREMENTS PER PRESSURE ZONE ADD = 23.58 MG MDD wlhrirg lkw 1.67 10 -.Ye Pqimmb = lox ADD = 235.80 MG (-)=~rnU&?b~ (+) =*drmgmTm. MASTER PLAN uLnwm STORAGE REQUIREMENTS PER TABLE 13 PRESSUREZONE J 'ASL Consulting Engineers CARLSBAD MUNICIPAL WATER DISTRICl CARLSBAD MUNICIPAL WATER DISTRICT WATER MASTER PLAN REFERENCES 1. MacDonald-Stephens Engineers, Inc. Water Master Plan CMWD Project No. 89-105. June 29,1990. 2. San Diego County Water AuthoriG. Groundwater Resource Development Repofi. August 1996. c 44