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Home My WebLink About08/20/1996, 5 - 1996 WATER RESOURCES STATUS REPORT council. Aust 20 199 aGEnba izEpoizt CITY OF SAN LUIS OBISPO FROM: John Moss, Utilities Director J^' Prepared By: Gary W. Henderson, Water Division Manager Gw� SUBJECT: 1996 Water Resources Status Report CAO RECONEMU14DATION Receive and file report. DISCUSSION The purpose of the annual "Water Resources Status Report" ( which replaces previous annual reports titled "Water Operational Plan") is to provide an overview of various issues associated with the City's water supplies. The attached report discusses four major topics: 1.) Existing Water Supply Status, 2.)Multi-Source Water Supply Projects, 3.)Water Conservation Program, and 4.) Projected Water Supply Situation. REPORT SUMMARY Existing Water Supply Status With the near normal rainfall this past year and the above average rainfall in 1994/95 the City's combined total water storage in Salinas and Whale Rock Reservoirs is 45,814 (as of May 1, 1996) which is 99% of the maximum City available storage. Groundwater production for 1995 was 250.5 acre-feet. The City's per capita water demand continues to increase from the low drought period (1991) use of 86 gallons per capita per day (gpcd) to 120 gpcd for 1995. This represents a 40% increase since exiting mandatory conservation in 1992. Long-term water use will likely continue to increase. Multi-Source Water Supply Projects One of the major goals of the Council is the pursuit of additional long term water supplies to meet the current and future water demands of the community The City is therefore pursuing the Water Reuse Project, Nacimiento Pipeline Project, and the Salinas Reservoir Expansion Project to meet these needs. The Water Reuse Project has the potential to be accomplished in the shortest time frame, with a projected water delivery as early as 1998. The Nacimiento Pipeline Project and the Salinas Reservoir Expansion Project are currently undergoing environmental impact assessment. Both projects are being pursued on a para" Council Agenda Report - 1996 Water Resources Status Report Page 2 track with the goal of completing the environmental impact reports at approximately the same time (late 1997). This will allow the Council to make an informed decision on which project(s) to proceed with to meet the City's additional water demands. Water Conservation The Utilities Conservation Office continues to implement the sixteen Best Management Practices (BMP's) established by the Urban Water Conservation Council. The key component of the City's continuing efficient use of water is water savings available through retrofit of existing toilets and showerheads with low flow fixtures. The retrofit of the community is being accomplished using three different programs: 1.) Retrofit Upon Sale; 2.) Retrofit Rebate; and 3.) Retrofit Offset (for new development). It is estimated that approximately 45% of the community as been retrofitted as a result of these programs. Projected Water Supply Situation The City utilizes a computer program to project how long the City's available water supplies would last based on a number of assumptions. The model uses historical worst case weather patterns, projected water demands, etc., to forecast the City's water supply position and to make certain water policy recommendations. With the favorable water supply situation, the model predicts current water supplies would last until July of 2002. FISCAL POPACT There is no fiscal impact associated with the recommended action. Attachment: 1996 Water Resources Status Report gAcarl96wrsr.car S�� City of San Luis Obispo 1996 WATER RESOURCES STATUS REPORT OVERVIEW The City of San Luis Obispo's first annual "Water Operational Plan" was adopted by the Council on June 4, 1985. The plan was prepared in response to the City's water demand exceeding the established safe annual yield from the water supply sources available to the City at that time. The annual reports were prepared for Council consideration each year thereafter (with the exception of 1994 & 1995) and were particularly important during the drought period of 1986- 91. After several years of drought, City water supplies were projected to run out and as such, the City was actively pursuing construction of a temporary desalination plant which was estimated to cost approximately $20 million. The "Miracle March" rains of 1991 added sufficient water to Salinas and Whale Rock Reservoirs to allow the proposed desalination project to be put on hold. With the exception of a limited amount of groundwater supplies, no new water resources have been acquired to meet the City's water demand since Whale Rock Reservoir was completed in 1961. Although the City is actively pursuing several water supply projects, there are many obstacles to overcome and timely completion of the projects is questionable. The purpose of the annual "Water Resources Status Report" is to provide an overview of various issues associated with the City's water supplies. This report discusses four major topics: 1.) Existing Water Supply Status, 2.) Multi-Source Water Supply Projects, 3.) Water Conservation Program, and 4.) Projected Water Supply Situation. I. INTRODUCTION The City Council adopted the Urban Water Management Plan (UWMP)on November 15, 1994. The UWMP establishes policies and directions relative to water supplies and deliveries to City residents. The 1996 Water Resources Status Report reviews the current reservoir storage and groundwater production situation and the status of the computer storage model, and then examines the supply and demand management in use or under evaluation at this time. With the normal rainfall this past year, the City's water storage has increased by 8% compared to last year at this time. It is important to note that even with the improved water outlook, indoor and outdoor water use efficiency must continue to be a high priority for the City. II. EXISTING WATER SUPPLY STATUS Rainfall totals for the period from October 1995 to May 1996 were near normal. The Salinas Reservoir received 20.41 inches of rain and the Whale Rock Reservoir received 18.11 inches. The abundant rainfall in 1995 resulted in a new 24 hour maximum rise in water levels at the Whale Rock Reservoir. The previous maximum was 3.5 feet for the 24 hour period occurring on February 25, 1969. The new record of 7.6 feet occurred on March 11, 1995. ,�•3 1996 Water Resources Status Report Page 2 The City's reservoir water supply is augmented by the use of groundwater. The City's groundwater production has experienced a significant reduction since 1991 and 1992 as a result of the loss of several key municipal wells due to groundwater contamination. The Auto Parkway and Denny's wells have been shut down due to elevated nitrate levels. The iJWMP identifies 500 acre feet per year of groundwater production as the basis for planning additional water supply needs. This past year's production (January 1 through December 31) was only 250.5 acre feet. As part of development in the Dalidio area, staff will investigate opportunities for increasing groundwater production by requesting a site for water treatment facilities. Another option would be to use the groundwater which does not meet drinking water standards as an additional source of supply for the water reuse project. This would increase the amount of water available for non-potable uses. The Salinas Reservoir began spilling on February 21, 1996 and continued spilling until April 28'". As of May 1, 1996, Salinas Reservoir was at 99.8% of total capacity (23,784 a.f.) and Whale Rock Reservoir was 99% of total capacity (the City's proportionate share of Whale Rock was 98% of the City's total storage or 22,030 acre feet). The combined total of 45,814 acre feet is 99% of the maximum City's available storage. This is approximately six years of water supply based on the computer storage model and assumptions listed in Figure 3. Water Consumption and Conservation The City exited mandatory water conservation in March 1992. Since that time, per capita water use has been increasing each year (Figure 4). Per capita water use reached a low in 1991 during mandatory conservation of 86 gallons per capita per day (gpcd). For 1995, the per capita use rate Table 1: Population Estimates was 120 gpcd. This represents a 40% increase since exiting mandatory conservation. TheF1,996 ear population increase may be attributable to the re-establishment of landscapes lost90 41j958 or damaged during the drought91 42,178 and maintaining existing landscape adequately. It should be noted92 421,922 that the population figures used to93 431397 calculate per capita water use rates are determined by the California94 43,919 Department of Finance. The95 41,295 population estimates for 1995 were 41j943 revised as shown in Table 1 and Figure 4 which indicates a 1996 Water Resources Status Report Page 3 reduction of 2,624 residents between 1994 and 1995.. This revision to the population estimates increases the per capita rate by approximately 4 gallons accounting for 5% of the total 40% increase. As identified in the UWMP, the per capita use rate utilized for projecting the City's long-term water supply needs is 145 gpcd. City residents continue to efficiently use water but long-term water use will likely continue to increase even with an ongoing water conservation program. Water Available for Development Based on the policies contained within the Water Management Element of the General Plan, there is currently no water available for allocation to new development. New development may only proceed at this time through the retrofit offset program. The policies require that new development reduce existing long-term water usage equal to twice the allocation required for the project. This is typically accomplished by retrofitting existing bathrooms with low flow toilets, showerheads, and faucet aerators. There are currently approximately 600 acre-feet of water available through the retrofit offset program. On July 2, 1996, Council adopted revisions to the Water Management and Land Use Elements of the General Plan that will allow a larger portion of the water available through the retrofit offset program to be used for new annexation areas. The policy prior to the recent revisions reserved the water available through the retrofit program for intensification and infill within the existing City limits as of July 1994. The new policy allows new annexation areas to use up to 300 acre feet of the water available through the retrofit program. III. MULTI-SOURCE WATER SUPPLY PROJECTS In November, 1990, the City Council adopted a multi-source water supply policy. The recently adopted UWMP Policy 2.7 reaffirmed the City's strategy of utilizing multiple water supply sources to meet our current and future water needs. The policy states that "The City shall continue to develop and use water resource projects to maintain multi-source water supplies, and in this manner, reduce reliance on any one source of water supply and increase its supply options in future droughts or other water supply emergencies." Policies which were adopted in the UWMP, Water Management and the Land Use Element have revised previous water demand projections. The projected total amount of water to serve General Plan build-out, under the revised plans and policies, is 11,596 acre feet. This figure includes the 2,000 acre-foot reliability reserve and 500 acre feet for loss due to siltation at the reservoirs. The City's current adopted safe annual yield from the reservoirs and groundwater is 7,735 acre feet. This results in an additional supplemental water requirement of 3,861 acre feet per year. 1996 Water Resources Status Report Page 4 Since one of the major goals of the Council is the pursuit of additional long term water supplies, the City is pursuing the Water Reuse Project, Nacimiento Pipeline Project, and the Salinas Reservoir Expansion Project to provide additional water resources for the community. The following is a brief status report on each of these projects being considered to meet the City's future water needs. Water Reuse Reclaimed water or water reuse will provide a reliable long-term water supply source for the City. Since the completion of a $30 million upgrade in 1994, the City's Water Reclamation Facility (WRF) produces a tertiary treated effluent. At this advanced level of treatment, the reclaimed water can be used for irrigation of parks, playgrounds, and all types of commercial and residential landscaping. It may also be used in industrial processes, for construction, and other non-potable uses. By using treated wastewater effluent for non-potable water demand such as landscape irrigation, a portion of the City's potable water will be made available for other additional potable uses. Staff has estimated that reclaimed water could offset 400 to 700 acre feet per year of a sting potable water demand for e_xistine non-potable uses and even more in future new development. Before reclaimed water can be delivered to customers, the following must be accomplished: ■ Prepare and certify the environmental documents • Prepare an engineering report and submit it to the Department of Health Services (DHS) and the Regional Water Quality Control Board ■ Establish user contracts and an ordinance requiring use when reclaimed water is available ■ Establish revenue program ■ Perform detailed design of storage, pumping and distribution facilities ■ Construction of distribution facilities A second Draft EIR for the project was distributed for public comment in December of 1995. It is anticipated that the EIR will be presented to Council for certification by the end of 1996. Staff has estimated that reclaimed water may be delivered to the first customers as early as 1998. 3'6 1996 Water Resources Status Report Page 5 Nacimiento Water Supply Project The County of San Luis Obispo is continuing to pursue the Nacimiento Water Supply Project to make beneficial use of its entitlement of 17,500 acre-feet per year (afy) of water from Lake Nacimiento. The current phase of the project involves the preparation of an Environmental Impact Report (EIR) and preliminary engineering analysis. The City of San Luis Obispo is participating in the project with an allocation request of 3,380 afy, as approved by Council on September 20, 1994. The cost of the EIR and Feasibility Reports is estimated at$1,260,000 or $77.78 per acre-foot of request. Therefore, the City's share of these costs is about $265,000. The engineering and environmental project descriptions have been completed and the Spring surveys are being conducted. This phase of the Nacimiento Water Supply Project is expected to take eighteen to twenty-four months to complete. Once the EIR is completed and certified, the County will initiate procurement of final participation agreements with the project participants. The County will then proceed with final design, engineering and construction. If the project continues to proceed on schedule, water deliveries from Nacimiento could occur around the year 2001. Salinas Reservoir Expansion Project The draft environmental impact report was released for public review and comments in November of 1993. The formal comment period closed on January 3, 1994. Many comments were received and a number of areas of potential concern were raised by individuals and regulatory agencies. Based on the comments received, Council approved additional studies and directed that the draft EIR be updated to more fully address the areas of concern. Council also directed that the project proceed on a parallel track with the Nacimiento Pipeline Project. The goal would be to have the EIR's for both projects completed at approximately the same time so that Council can make an informed decision on which project(s) to proceed with. Additional biological studies required by the regulatory agencies are underway. Additional analysis to address concerns raised by downstream water users will begin this summer. Following the completion of these studies, the draft EIR for the Salinas Reservoir Expansion Project will be updated and released for public comment in early 1997. Certification of the EIR is expected by the end of 1997. Groundwater Wells The current groundwater program utilizes three wells for domestic use, two wells for irrigation at the City golf course and one well for construction water uses. The City's two largest producing wells, the Auto Parkway and Denny's wells, have been shut down due to elevated nitrate levels. The Pacific Beach #1 & #2 wells are not operated simultaneously due to well S_7 1996 Water Resources Status Report Page 6 interference problems between the two sites. At this time, wells are producing approximately 20 acre feet per month which represents about 4% of the total City water demand. The relatively small groundwater basin which supplies the majority of the groundwater production is recharged very quickly following normal rainfall periods. The water levels in the basin also fall relatively quickly following the end of the rain season. This fluctuation of the basin limits the amount of water that can be withdrawn on an annual basis. The UWMP has adopted a goal of 500 acre feet per year of groundwater production. This past year's production from the available wells was only 250.5 acre feet. Extensive use of groundwater sustained the City through the last drought. With the loss of the Auto Parkway and Denny's wells to nitrate contamination, the City can not rely on groundwater for future drought protection. Cloud Seeding The City of San Luis Obispo initiated a cloud seeding program in January of 1991 due to limited water supplies and the continuing drought. Atmospherics Incorporated of Fresno, California was selected to provide a three-year cloud seeding program. The third year of the program was terminated following heavy rains in December and January of 1993 and the impending overtopping of the Salinas Reservoir. The program targeted both the Salinas and Lopez Reservoirs and the City and County shared the costs for the program. Since the Whale Rock Reservoir drainage area is relatively small and the runoff characteristics are not as favorable, it was determined that Whale Rock is not a good candidate for cloud seeding operations. Cloud seeding programs may be warranted in the future when water levels drop significantly at Salinas Reservoir. Since this year's rains have filled Salinas Reservoir to capacity and water levels will not drop significantly prior to next winter, cloud seeding is not recommended for the upcoming season. IV. WATER CONSERVATION PROGRAM Water conservation has played an ever increasing role in the City's over-all water supply development and management strategies since 1985. With the adoption of the Urban Water Management Plan (UWMP) in November 1994, the policies regarding water conservation will provide the essential foundation in sustaining long-term water supply dependability by using our existing supplies more efficiently. In September 1991, the Council approved and authorized the Mayor to sign the "Memorandum of Understanding" (MOU) with the Urban Water Conservation Council regarding urban water conservation and the implementation of the sixteen "Best Management Practices" (BMPs). The BMPs were presented as part of the UWMP. The MOU acts as a road map for the City's long- term water conservation program and signifies a commitment to the BMP process. c� O 1996 Water Resources Status Report Page 7 The following information is a summary of the water conservation program's key components: Retrofit Rebate Program The retrofit Rebate Program has been in effect since 1990. It is important to note that funding levels and rebate reimbursements varied from 1990 through the fiscal year 1992/93 as noted in Table 2. Program participation has fluctuated since 1990 and can be attributed to following factors: ■ 1990/91-The City was in mandatory water rationing and program funds were expended in a four month period. ■ 1991/92-Participation decreased primarily due to reduction in the rebate amount offered from $80 to $70 per bathroom. ■ 1992/93- Participation increased during 1992/93 because of the increase approved by Council from $70 to $100 per bathroom. ■ 1993/94- Participation decreased which can be partly attributed to the elimination of promotional funds for the fiscal year. The public was not aware that the program was still in effect. ■ 1994/95- Participation was again down because funds were not available to promote the program and the abundance of rainfall lessened the previous impacts of the drought. ■ 1995/96- Participation decreased further primarily associated with an increase in the Water Offset Program activity which offered free retrofits to customers. All rebate retrofits represent an approximate water savings of 175 acre feet per year at an amortized cost of approximately $300 per acre foot. Retrofit Upon Sale Program The Retrofit Upon Sale Ordinance was adopted in October of 1992 with an effective enforcement date of January 1993. After approximately 3 1/2 years of enforcement, the ordinance has been very successful and with extensive staff effort has been well received by the real estate and escrow business community. This is a staff intensive program requiring monitoring of compliance, tracking escrow closures, issuing follow-up correspondence, issuance of the "Water Conservation Certificates" (WCC) and entering information into the master retrofit database. �-9 1996 Water Resources Status Report Page 8 Table 2: Summary of Retrofit Rebate Program Fiscal Year 1l of Funds Funds Rebate Toilets Allocated Expended Amount 1990/91 1,250 $100,000 $100,000 $80 1991/92 942 $100,000 $65,990 $70 1992/93 1,313 $137,500 $133,550 $100 1993/94 898 $137,500 $85,230 to$100 1994/95 896 $137,500 $83,777 to$100 1995/% 551 $100,000 $52,655 to$100 (as of 6/96) Table 3: Summary of Retrofit Upon Sale Table 3 summarizes the Program retrofit upon sale activity since the ordinance went into effect. Year # of Issued WCC N of Bathrooms It is important to note that 1993 730 1,518 people required to retrofit 1994 649 2,205 their property upon sale 1995 855 3,012 are eligible to receive a _T rebate. Also, developers 1996 (as 260 567 that need to retrofit as a of 6/96) condition of project approval often retrofit homes that are being sold, therefore the numbers listed in Table 3 may also be included in Tables 2 and 4. Additionally, WCC are issued and logged into the computer data base system when staff verifies that a property has been completely retrofitted. Water Offset Program The Water Offset Program was established as part of the Water Allocation Regulations to allow development when there is no water available to allocate. Developers must make changes, in facilities served by the City, which will reduce long-term water usage by twice the allocation required for the new project. ICIIA 1996 Water Resources Status Report Page 9 Table 4: Summary of Water Offset Program Table 4 summarizes the retrofit activity through the Water Offset Program for the last Year #of #of four years. Bathrooms Locations 1993 1,261 538 Water Audit Program 1994 1,727 124 The water conservation office offers free 1995 2,208 525 indoor and outdoor water audits upon request. 1996 (as 207 63 The requests are received from people of 6/96) experiencing high water bills, residents participating in the low income assistance program and customers requesting a utility bill adjustment through the Utility Billing Adjustment Committee. During the 1995/96 fiscal year the office performed approximately 250 water audits for both residential and commercial customers. Public Information & Education In its ongoing effort to educate the public on efficient resource utilization, the water conservation office in conjunction with other City departments has developed the W.I.N. (Worldng to Improve our Neighborhoods) Program. The initial focus of the program is on appropriate landscape installation and maintenance which has both a monetary and social value to our community. The Utilities Conservation Office continues to provide water conservation information upon request and other valuable services for the community. V. PROJECTED WATER SUPPLY SITUATION Reservoir Storage Curve The Reservoir Storage Curve is integral to the City's annual water plan analysis. It is a computer model used to estimate the City's future reservoir storage based on historical water use, weather patterns, reservoir data and available groundwater supplies. The model is used to forecast the City's water supply position and to make certain water policy recommendations. The curve has been updated to reflect the City's current storage and the policies contained in the Urban Water Management Plan. The model predicts current water supplies would last until July of 2002, under a set of assumptions that represent the weather patterns during the drought of 1986-91. 1996 Water Resources Status Report Page 10 SUNS IARY The City is in a favorable water supply situation with the abundant rainfall in 1994/95 and normal rainfall in 1995/96. Even with this improved short-term outlook, the need for supplemental water supplies is evident and the continued efficient use of water is crucial. With the multi-source water policy, strong water conservation program and other related policies which were adopted as part of the UWMP, the City is pursuing a direction which will create a reliable supply of water to meet our customers current and future needs. Attachments: Figures 1-5 FIGURE 1 RESERVOIR RAINFALL RAIN YEARS 1991 /92 - 1994/95 6 55 5 39.86 45 Z32.28 Q 4 33.94 CZ 3 LL 5 Q 3 2246 26.6 cn 20.55 LLJ 25 17.91 2 U 20-/ 1621 Z 13.13 15 10 5 Salinas Dam Whale Rock 0 90/91 91/92 92/93 93/94 94/95 Rain Year Totals (Oct - Sept) ANNUAL RESERVOIR RAINFALL 1980 - 1995 48.76 5 50.0 38.48 Z 4 Q 3 26.94 27.3 30, LL 25. •68 23.08 3 3 W ,53 16.80 21. 7 22 U9 18. 1 13.4 ' 6 17. 6 Z .78 6 1 1 Salinas Darn Whale Rods 1980 1981 1982 1983 1984 198.5 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 Calendar Year Totals ,S•/3 I® - I IIS • IIII® IIIA-® ❑Ili,....® �m ie \® A\\® FIGURE 2 coo •... 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