Loading...
HomeMy WebLinkAbout; MASTER PLAN FOR PUBLIC WATER SYSTEM; MASTER PLAN FOR PUBLIC WATER SYSTEM IMPROVEMENT DISTRICTNO 2 - WEST OF EL CAMINO REAL; 1975-02-05WOODSIDK/KUBOTA A ASSOCIATES, INC. 2965RooseveltSt. .P.O. Box 1095'Carlsbad, California 92008 • (714)729-1194 February 5, 1975 Board of Directors Carlsbad Municipal Water District 6480 El Camino Real Carlsbad, Calif. 92008 Subject: Master Plan for Public Water System Improvement District No. 2 - West of El Camino Real Gentlemen: We are pleased to submit herewith our engineering report entitled "Master Plan for Public Water System - Improvement District No. 2 - West of El Camino Real". This of two separate authorizations Study" and the "Frank H. Ayres to the initiating of these two our recommendation, authorized report for the entire area of of El Camino Real. project represents a combined study , namely the "Poinsettia Avenue Area & Son Properties Study". Subsequent separate studies, the Board, upon the development of one comprehensive Improvement District No. 2 westerly Briefly, the report identifies in detail the extensive and substantial public water system that we envision will be required to match the needs of the various land uses as set forth in the latest land use plan adopted by the City of Carlsbad. As expected, there was a sub- stantial increase in pipeline capacities and reservoir storage re- quirements over the current operations, which to date have served well the predominant agricultural activities. We recommend that the District and all interested parties review this proposed master plan in detail and we invite any comments, suggestions, and questions. After thorough review and evaluation the District should consider the formal adoption, modified as necessary, so that it will serve as a viable reference as new development activity and public water system expansion continues. ^-Very truly yours ^ JYK/le In Oranaa County, Sente Ana /Jack Y. Kubota, District Engineer LCarlsbad Municipal Water District WOODSIOK/KUBOT* « ASSOCIATKS. INC BBB WOOD IS MASTER PLAN FOR PUBLIC WATER SYSTEM IMPROVEMENT DISTRICT NO. 2 - WEST OF EL CAMINO REAL INTRODUCTION The Carlsbad Municipal Water District developed an extensive arterial water system in 1959 to bring to the area of Improve- ment District No. 2 its first public water system. Immediately, the entire area became very attractive to agricultural interests and irrigated agriculture soon covered the rolling hills and fertile valleys. Throughout most of the 1960's agriculture predominated in the sector westerly of El Camino Real but urbanization commenced in the early 1970's. In particular, the area of the Poinsettia Avenue interchange with 1-5 Freeway and the "Schuyler Ranch" has come under new development so that a detailed evaluation of the public water system became apparent with the changing land uses and attendant water system requirements. Likewise, the Frank H. Ayers and Son properties had been completely "master-planned" for urban development resulting in the need to study the water system requirements for that area. Accordingly, the District authorized two separate engineering studies to analyze the overall system requirements and the relationships with other fringe areas. On the basis of detailed work on the two studies a determination was made that an overall study for the entire area of I.D. No. 2 westerly of El Camino Real and southerly of Palomar Airport Road was the most effective way to pursue the project. It is timely that this project was authorized and pursued as the recent development activities has raised a number of issues as to the practical plans for providing compiete water service to the residences, commerce, industry, and the public facilities. With the completion of th'i s study the entire area of I.D. No. 2, with the exception of a small portion of the Bressi Ranch and the La Costa North area, has been given a detailed engineering evaluation for the updating of the master plan of public water system originally developed and adopted in 1959. It is fortunate that the District has been able to adhere to the overall goals of that original master plan and to have the opportunity to observe closely development trends so that the current updating of the plans can be effective to accommodate the i mmedi ate water service requi rements and the projected needs of the developi ng areas. WOODSIDK/KUBOTA « ASSOCIATKS, INC. We acknowledge the generous assistance and cooperation of the Planning Department of the City of Carlsbad, who provided all of the input for land use, zoning, and population projection. In addition, the Fire Department and the Engineering Department of the City of Carlsbad assisted in the determination of practical levels of water service demand and development needs. II. SCOPE AND PROCESS OF STUDY The limits of the study are as shown on the "Master Plan for Public Water System - Improvement District No. 2 - West of El Camino Real" area on the map marked "Exhibit B", an attachment to this report. This area, in general, consists of those lands lying between Palomar Airport Road on the north. El Camino Real on the east, Batiquitos Lagoon on the south, and the Pacific Ocean on the west. The topography of the area is made up of mesas penetrated by deep valleys running northerly and southerly and by lower mesa lands between 1-5 Freeway and the Pacific Ocean. The total area that is under consideration is approxi- mately forty-two hundred (4,200) acres and the land elevations range from sea level to an elevation of 384 feet. The land use and population in the a rea was determined from the City of Carlsbad's Land Use Plan. Population was calculated using the maximum allowable density for each particular area. The operating pressures within the study a re a were redefined and new pressure zones proposed. These zones a re set using current development trends and California Department of Public Health guidelines. The minimum allowable pressure has been set at 40 psi and a maximum allowable pressure of 125 psi. The minimum pressure may be as low as 20 psi under fire flow conditions and the maximum pressure may be higher under low flow or static conditions. The hydraulic parameters upon which the study is based are consumption data based on District records and previous studies within the District of 170 gallons of cons urnption per capita per day. The maximum daily consumption per capita was set at twice the average daily consumption of 170 gallons or 340 gallons per capita per day. A peak hour demand was estimated to be twice the maximum daily consumption or 680 gallons per capita. Pipe sizes we re calculated using the maximum day plus fire flow or peak hour demand, whichever was greater. - 2 - WOOD TB WOODSIOK/KUBOTA « ASSOCIATES. INC mt Water consumption for open spaces, commercial and institutional (schools) areas was assigned an annual factor of 2.5 acre feet per acre. Water consumption within industrial areas was assigned an annual factor of 3.5 acre feet per acre with the exception of the Palomar Airport Business Park which has a fixed flow of 2,000 gallons per minute as determined at the time this industrial subdivision was approved. The estimated fire flows were determined with the guidance of the Fire Department of the City of Carlsbad utilizing current Insurance underwriter's requirements based on a prediction of the type of construction that will be used in the area. The subject fire flows are summarized in Table I of this report. Water main size was determined using a maximum velocity within the pipelines of 8 feet per second and a minimum pressure of 40 psi, except during fire flow conditions when residual pressures of 20 psi are allowed. The maximum flow in each of the pipelines was based on the maximum daily consumption plus the required fire flows or peak hour demands, whichever is greater. In addition, the pipelines a re sized so that head losses due to friction will not result in pressure reductions below those previously stated. Maximum operating pressure has been set for 136 psi except in industrial a re as where higher pressures are allowed. This high pressure represents a maximum pressure at static conditions and will occur in the 318 zone at sea level. III. LAND USE The study area consists of lands that are within the City of Carlsbad and lands that are within the County of San Diego. The City of Carlsbad adopted a Land Use Plan on August 16, 1974 by City Council Resolution No. 3527 and this Land Use Plan includes all of the area within this study and as shown on "Exhibit A" of this report. The principal land use designations of res 1 den ti al, commerc ial, recreational -comme rcial, parks and schools a re shown on "Exhibit A". In addition to this Land Use Plan, there are various approved tentative maps and recorded subdivision maps in the a re a. Where available, this detailed in format ion was used to make the study more definitive and preci se. Those areas that are presently developed and where there are •mt approved tentative maps and tract maps, the exact densities as shown on these maps were used in the computation of the popu- lation for the a re as. The population was estimated on the basis of an average of 2.9 persons per dwelling unit. The 2.9 - 3 - ml WOODSIDK/KUBOTA A ASSOCIATES. INC- persons per dwelling unit is the factor the City of Carlsbad Planning Department currently uses in estimating populations on a city-wide basis irrespective of the particular type of development; i.e. condominium, single family residences or multiple residential structures. For those areas where there was no Information other than the Land Use Plan, the population and density estimates were made using the maximum densities as shown on the plan. Based upon the Land Use Plan and utilizing the 2.9 persons per dwelling factor, the ultimate population is estimated to be 58,000 people. Table II is a summary of the projected population and land use IV. EXISTING DISTRICT FACILITIES The District maintains and operates numerous existing pipelines within the study area. These existing pipelines are shown on the attached "Exhibit B". In addition to the pipelines, the District presently has two above-ground reservoirs that are located at Elevation 384. These reservoirs a re known as D-1 and D-2, Improvement District No. 2, These reservoirs have a combined capacity of 2.5 million gal Ions . The study area receives its water from a 20" connection to the 27" pipeline in Palomar Airport Road at Its Intersection with El Camino Real. The 20" pipeline continues southerly in El Camino Real for approximately 6,300 feet. An 18" pipeline runs to the west from El Camino Real to the D-Reservoirs. A 12" pipeline continues south In El Camino Real to La Costa, In addition to these lines in El Camino Real, there is a 16" pipe- line that parallels the 20" in El Camino Real from Palomar Airport Road to the south boundary of the Carlsbad Business Park. This 16" pipeline will be continued in the future as shown on "Exhibit B". The above described pipelines bring the water supply into the area. In addition, the District has numerous major pipelines that distribute water within the areas as shown on "Exhibit B". The study a re a is currently served by two pressure zones. High pressure water for the area in 664 hydraulic gradient water and the remaining area is serviced by 384 hydraulic gradient water. The District operates two Pressure Regulating Stations; the El Camino Real Pressure Regulating Station and the "D" Reservoir Pressure Regulating Station. - 4 - ' III • WOODSIDK/KUBOTA A ASSOCIATES. INC •• PROPOSED ARTERIAL WATER SYSTEM The study area Is currently served by two pressure zones. It was necessary that the pressure zone definition in the area be redefined and new pressure zones established that meet current development trends and State Department of Public Health guidelines. The study area was divided into three pressure zones. The pressure zones are as listed in Table III and the exact areas of these zones are as shown on "Exhibit B". Zone I is served by water having a hydraulic gradient of 318 feet and the elevations within Zone I vary from sea level to an elevation of 120 feet. Zone II is served by water having a hydraulic gradient of 384 feet and the elevations of the land served by this water is from 120 feet to 260 feet. Zone I and II are served by the reservoirs as shown on "Exhibit B". Zone III is served by hydraulic gradient water of 550 feet and the elevations served are 260 feet to 384 feet. The areas within this pressure zone do not have local storage and are dependent upon high pressure water from the San Diego County Water Authority's aqueduct and Squires Dam in times of emergency although Squires Dam will not supply water of the 550 foot gradient. The 550 foot zone could drop to 475 at the static conditions since the active storage zone in Squires Dam is Elevations 475-505 feet. These pressure zones can be varied slightly and accordingly the pressure reducing stations as shown on "Exhibit B" may be relocated depending upon the type of grading operations of specific developments within the various areas. The El Camino Real Pressure Regulating Station will be relocated and enlarged in the vicinity of the Intersection of El Camino Real and Alga Road. The Pressure Regulating Station at D-Reser- voirs will remain and be enlarged as necessary when additional storage capacity is constructed. A major pressure reducing station in this system will be located at Palomar Airport Road and El Camino Real. This* pressure re due ing station will reduce pressure in the existing 20" line in El CamIno Real that goes south from Palomar Airport Road as well as paralleling the 16" line that has been construe ted on the west side of El Camino Real. These pressure reducing stations will be constructed with sustaining features so that they will maintain a minimum upstream pressure and utilize the maximurn capability of the storage that is required at the D-Reservoir site. "Exhibit B", attached to this report, shows the proposed arterial pipeline system for the study area. Section VI of this re port entitled "Storage Requirements" will demonstrate that all of the storage for the area is limited to two sites that are within 2,000 feet of each other. This eliminates the need for duplicate - 5 - WOODSIDK/KUBOTA A ASSOCIATES. INC pipelines to supply individual reservoirs that could be located at lower elevations. As a result, economy will be realized since the necessity of providing two lines in the same area has been minimized to two locations in the Pressure Zone III. Pressure Zone III has been kept to a minimum of area to keep the necessity for double lines and those areas that will not have local storage to a minimum. The minimum size and number of arterial mains and loops are shown on "Exhibit B". The size of the mains and the spacing of the loops depends entirely on localized demand and fire flows. Since fire flows are expected to be a minimum of 1,500 gallons per minute in the residential areas to a maximum of 6,000 gallons per minute in the commercial and industrial areas, the line size that is proposed for arterial mains is ,12" and the spacing is at one-half to three-quarters of a mile intervals. In this way all of the required quantities can be delivered without excessive veloci ties. The type of structures that are proposed to be constructed are unknown, however, we assume there will be normal single family residential construction and condominiums with no more than two stories and meeting Fire Department requi rements for the fire flows listed for each density and land use as shown on the Land Use Plan. If, in the future, high rise construction or any other high-density type construction is allowed, the fire flows and demands may change substantially and pipeline capacity into those areas would have to be re-evaluated at that time with respect to the adequacy of the sizing of the pipe and the supply available. This is also the case within industrial and commercial areas if high water use industrial and commercial establishments are allowed and there may be a requirement for on-site storage or some other means to satisfy peak water demands as we 11 as possibly their fire flow requi rement due to extremely 1arge structures. This arterial system will provide for a flow of 2,000 gallons per minute at the Palomar Airport Road metering station for supply to the City of Carlsbad service area (Terramar). The City of Carlsbad's total flow requirement in the Terramar area has been estimated at 5,000 gallons per minute. The additional flow requirements to the City of Carlsbad will be handled by other connections which come from the east in the a re as northerly of Palomar Airport Road. The proposed arterial system is a plan for major transmission facilities only. Each development will be required to build local distribution mains that are appropriately looped and meet the design criteria of the District and the Fire Agency having jurisdiction. The exact location of these major facilities may be changed to conform with proposed road alignments and local subdivision streets. - 6 - HHH WOOD: WOODSIOE/KUBOTA A ASSOCIATES. INC VI . STORAGE REQUIREMENTS The study area has been divided into three pressure zones as shown on "Exhibit B". The existing D-Reservoirs have the capability of serving Zones I and II. Zone III cannot be supplied by the existing reservo1rs or any new reserve 1rs that must be constructed. Storage for Zone III must be provided by construction of storage in another area and the storage requirements must be Included in studies of the surrounding area in the future. The Pressure Zones I and II will be supplied by the existing D-Reservoirs and additional storage to be constructed in the future. Zone I and II will have a maximum population of 49,000 people based on the Land Use Plan, The storage require- ments for this population is a total of 17.0 million gallons which is equal to one maximum day of water usage. The District presently has 2.5 million gallons of above ground storage at the existing D-Reservoir site. This site Is not large enough to accommodate 17.0 million gallons of total storage. There is, however, a site approximately 2,000 feet to the south of the 0-Reservoir site that can accommodate the District's sto rage requi rements. There are several options for meeting storage requi rements open to the District, Among these options are the following: 1. There is sufficient room for the construction of two additional 1.25 million gallon re servoirs on the existing site. The additional 12.0 million gallons will be constructed at the new reservoir site. 2. The District may construct two more 1.25 million gallon reservoirs at the existing site and construct two 6 million gallon reservoirs at the new site. 3. The District may use the existing 2.5 million gallons of storage at the "D" site and construct 14.5 million gallons of sto rage at the new site. The 14.5 million gallons may be constructed as one reservoir or as a 7 million gallon and 7.5 million gallon reservoir or other similar combination of sizes totaling 14.5 million gallons. 4. Construct the entire 17.0 million gallons of storage at the new proposed site and remove the existing D-1 and D-2 reservoi rs. - 7 - • HI WOOD! n WOODSIDE/KUBOTA A ASSOCIATES, INC With the exception of Alternate No. 4, the District may phase the construction of the requi red storage as the area develops. In the event the total population is less than the maximum projected, the District will not have to construct the entire additional 14.5 million gallons of sto rage, if the construction is phased. A detailed analysis of these options will have to be made at the time additional storage is requi red. VII. SUMMARY AND CONCLUSIONS The original "Master Plan for Public Water System - Improvement District No. 2" has served well the variety of agricultural acti- vities and the early stages of urban development. The recent completion of the Land Use Plan by the City of Carlsbad has permitted a level of study and analysis so that all of the public water system facilities can be developed in concert with the up-to-date planning and zoning. The appraisal of the public water system requirements based upon today's measure of design and standards has resulted in a basic arterial water system, which should adequately serve the area as urban development set forth in the current Land Use Plan takes place. Our analysis and evaluation of the adopted Land Use Plan resulted in a population projection of some 58,000 residents within the 4,200 acre study area. In addition, there is a potential of commercial, industrial, and vast open spaces and public facili- ties identified in the Land Use Plan. Taking into account the projected water demands for these activities and the important factor of fire flows, detailed engineering analysis has yielded the various design flow requirements and elevated storage require- ments for the entire study area. The proposed Master Plan as set forth in this report is intended to represent the public water system utilizing to a maximum the existing pipeline capacities, storage reservoirs and appurtenant faci1i ti es. VIII. RECOMMENDATIONS 1. The proposed Master Plan for Public Water System should be thoroughly reviewed and evaluated by all interested parties including the various property owners and governmental agencies, who have a substantial interest in the entire study area. We will be witnessing a substantial increase in development activities in the next several years to come, so that it is important we have continuing participation and input from all interested parties. - 8 - WOOD tfHOIHKKIIB WOODSIDE/KUBOTA A ASSOCIATES, INC 411. -mt 2. After a suitable period of time of review, the plan should be formally adopted by the Board of Directors subject to those modifications as deemed appropriate. 3. The District should consider the integration of the various master plans for the sectors of Improvement District No. 2, as well as integration of Improvement District No. 2 with the entire District water system as a whole. Because of the interdependence of the various reaches in terms of pipe- line capacity, pressure regulations and storage require- ments, it is imperative that there be full continuity within all reaches of the District. / 4. Inasmuch as land use planning is active and viable, the District should monitor closely any significant trends for the modifications of the plan upon which this study is based Stated another way, a master plan, such as this, should be reviewed at least every two to three years, based upon the activities that have occurred. - 9 - HHH WOOD WOOOSIDE/KUBOTA m ASSOCIATES. INC. •HBIMBBHa TABLE I FIRE FLOW REQUIREMENTS LAND USE 1 . RL - Low Dens 1ty 2. RLM - Low Medium Density 3. RM - Medium Density 4. RMH - Medium High Density 5. Commercial - Residential Shopping Center 6. Commercial - Industrial Regional Shopping Center FIRE FLOW 1500 - 1750 gpm 1750 gpm 2500 gpm 3000 gpm 3000 - 4000 gpm 4000 - 6000 gpm - 10 - HHH WOOD WOODSIDE/KUBOTA A ASSOCIATES. INC BHoiMBaa* LAND USE AREA IN ACRES TABLE II LAND USE SUMMARY MAXIMUM DENSITY UNITS/ACRE TOTAL UNITS MAXIMUM PROJECTED POPULATION RL 95 1.5 143 415 RLM 1 ,458 4.0 5.793 16.800 RM 1 ,205 10.0 9,563 27,732 RMH 330 20.0 4,555 13,208 RH 30.0 RRI - - - RRE - ^ _ RS - C 23 N 24 TS 7 RC 33 CBD E 20 J 43 H 68 HC P 0 PI 399 G 30 V 14 OS 434 NRR 17 TOTAL 4,200 20.054 58,155 NOTE: Population and total approved developments units have been adj us ted to Include - 11 - BHH WOODSIDE/KUBOTA A ASSOCIATES, INC BHOIHBailB RE ZD to KD CO UJ CO I— CM to CD r— r— r— Ul z: 1 1 1 <c to V£) CM cu or Q. CO LO ^ ^ * CO t>0 i/i to to <• U. Ll-u. o tJ (_3 o :c CO r— • . . • 1— CO CO CM •~ , , * CM t>0 t/> to — U-U-u_ u. o c_> t_) o .-o ro o CO KD • • . • CO CO CM ••" t— r— UJ Cd '—. r— * ^—' t/) tn tn to u. U-U-Li_ t-1 UJ Q o C_J o t_) '—~ •«* l-H ct: < o CO o . . UJ z KD ro _] < 1— CM CO ro 1— UJ E ro o s. M L. UJ 1— o:: Q O ' "»» UJ *—1 CO 1— h-CM ID •o oo r— m ro Jtt Ul CO t£) 1— r— Xl »-< rD n n to D-1— D_ r— cn CO C/) O CM IS) S-c Ul a. m ceo tj CJ o •>- •r- -r- +J 4-+J 4-> Q- O O. D. E z: E E 3 o >> 3 3 (/) o o O 4J W VI c 1— Ul CM KD 00 •r— ceo cC >• ,-~ CM CO O ooo > CH 1 1 t o o LU LU o O o s-_J t/1 CM KD o >> >1 3 •Mn LU CM M-ro ro o Q o n: 00 u_ (DEE o C7> 3 3 ••m •-H 1— roes _J 21 LO ^ UJ • <U X X > ro ro Q 1— «s: E s: O < Ul CO O to >- Oi Ul r— CO ID 1 1 1 n: o u-CO CO in -o O CJ tJ ,— Q Q 3: <c E s: _l c Ul •a: 1—1 '—-'•——>• 1—« h-.— CM CO o 1—1 t—t *—( O + '—•"•— 1— 1 o I j LEGEND, WATER MAINS. EXISTING 61'&B"---- 10" 14" 18' 27 ... 2011 24" I> [> [> I> [> [> [> 0000(1()()() llllllllllilll!llllltlllllll 00000000 vxx.>v.xxxx - PROPOSED ►► ... ►►►lo­ ;6,, ,, ;1 rJ "Iii"' 'tillinili11i,1ii:.ttffvMI E)llSl'. PAOP. PRESSURE REGULATOR-{:>- NORMALLY CLOSED VALVE PRESSURc ZONES I II ill i......;;;;.;1 • · ......... ···•••••·· 1 i> :: 1 rt?KJfa-1 0 STUDY LIMITS _____ lllllllllllll EX1-1IBIT 'B' , · (BASE MAP) IMPROVEMENT WEST OF EL MASTER FOR DI STRICT NO. 2 CAMINO REAL PLAN y ?H PUBLIC WATER SYSTEM CARLSBAD MUNICIPAL WATER DISTRICT PREPARED BY: WOODSIDE -KUBOTA & ASSOC. ' CONSULTING ENGINEERS CARLSBAD, CALIFORNIA FEBRUARY 1975 NOTE : CONNECT ADOPTION BY BOARD OF DIRECTORS: RESOLUTION NO. 342 APRIL 7, 1976 0 J / CMtC/0 7.37/