Groundwater Resources Are in Long-Term Balance in Accordance with the Conjunctive Management Element of the City’S Long-Term Water Supply Plan
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6-a CITY OF SANTA BARBARA COUNCIL AGENDA REPORT Draft AGENDA DATE: January 23, 2018 TO: Mayor and Councilmembers FROM: Water Resources Division, Public Works Department SUBJECT: Drought Update and Annual Water Supply Management Report RECOMMENDATION: That Council: A. Receive an update on the status of the current drought, drought-response capital projects, and continuing efforts; and B. Approve and adopt the City of Santa Barbara Water Supply Management Report for the 2017 water year, finding that groundwater resources are in long-term balance in accordance with the conjunctive management element of the City’s Long-Term Water Supply Plan. EXECUTIVE SUMMARY: Since January 2014, staff has been providing monthly drought updates on water supply status, drought-response capital projects, community conservation, and other drought- related issues. Staff will provide a monthly update for January 2018. In addition, staff will present the 2017 Annual Water Supply Management Report (WSMR). The 2017 WSMR is a backwards-looking document that summarizes water supplies and issues for the water year that occurred from October 2016-September 2017. The report fulfills a mitigation requirement of the Coastal Branch of the State Water Project to manage water supplies to prevent long-term overdraft of local groundwater. DISCUSSION: Drought Update Council declared the Stage One and Stage Two Drought Conditions on February 11, 2014, and May 20, 2014, respectively, as a result of unprecedented drought conditions. On May 5, 2015, in response to the driest consecutive four-year period on record, Council declared a Stage Three Drought Emergency. Since then, the Stage Three Drought condition has been amended with appropriate conservation targets and water use regulations in response to current and forecasted supply conditions. Council Agenda Report 6-a Drought Update and Annual Water Supply Management Report January 23, 2018 Page 2 On December 6, 2016, the Stage Three Drought condition was amended to increase the City's water conservation target to a 40 percent reduction, based on local water supply conditions. On March 21, 2017, the Stage Three Drought condition was amended to decrease the City’s water conservation target to a 30 percent reduction in response to rainfall in the springDraft of 2017, which filled Gibraltar Reservoir and increased storage in Lake Cachuma. This drought update will cover the following items: Water Supply Outlook/Weather Forecast; Drought Response Capital Projects; and Conservation Efforts. Water Supply Outlook/Weather Forecast Despite above-average rainfall in January and February of this year, the average rainfall for the last six years still remains one of the lowest on record. Consistent with the City’s Long Term Water Supply Plan, depleted surface water supplies were replaced with increased groundwater production and purchases of supplemental water. As a result of increased pumping during the drought, groundwater levels are at historic lows. While a three-year supply planning outlook indicates the City is still in a drought and must continue to conserve, the City’s water supply plan has shifted in response to the last winter’s rains. Above-average rainfall in the month of February 2017 filled Gibraltar Reservoir and increased storage in Lake Cachuma to 50 percent. The City and other Cachuma Member Units saw an increase from a zero percent annual allocation to 40 percent annual allocation from Lake Cachuma for this water year. As a result of the modest improvements, the City’s water conservation target has been reduced from 40 percent to 30 percent, and the mandatory turfgrass watering ban has been modified to reflect voluntary turfgrass water cessation. In addition, groundwater wells were turned off to conserve water in the groundwater basins, while water from Gibraltar Reservoir and Lake Cachuma are being used to supply City customers. This strategy will enable water demands to be met through 2019, assuming there continues to be at least 30 percent reduction in customer water use. A new water year began on October 1, 2017, marking the beginning of the 7th water year since Cachuma last spilled in May 2011. Even though the water year officially starts in October, the City typically receives most of its rainfall from January through March. As with every new water year, the City’s water supply planning charts have been updated to reflect actual water used during the previous 2017 water year (October 1, 2016 – September 30, 2017), and the supply strategy has been extended one additional year through 2020 for drought planning purposes. The projections currently show additional water shortages in 2020, assuming no significant inflow to Gibraltar and Cachuma over the next three years. Staff will reassess the water supply strategy in the spring of 2018 after the next rainy season, and adjust conservation targets, as necessary, in order to provide sufficient supply through 2020. Rev. 011217 Council Agenda Report 6-a Drought Update and Annual Water Supply Management Report January 23, 2018 Page 3 Water Quality City staff are prepared for this winter’s potential water quality impacts from runoff from the Rey Fire, Whittier Fire, and recent Thomas Fire. Following the 2007 Zaca Fire, the City made significantDraft investments to its management of water, treatment, and distribution, which has put the City in the best position to deal with difficult surface water quality. Major changes that address water quality included the addition of ozone treatment, an active carbon feed system, circulation and aeration of water in its treated water reservoirs, and pretreatment of surface water in Lauro Reservoir. In addition, the frequency of surface water monitoring has been increased to help with adaptive water management of the City’s diverse water supply portfolio. Drought Response Capital Projects The Desal Plant has completed the contractual requirements for the start-up and testing phase. There still remain a few punch list items to complete but overall the facility is finished and operating. The temporary repairs to the intake pipeline have shown no signs of leaking but staff continues to work with the contractor to identify a long term repair solution. As the City moves into lower winter water demands, and as groundwater wells are turned-off for resting, desalinated water will play a critical role in meeting the City’s water needs. Conservation Efforts The City’s 12-month running average water conservation reduction at the end of December 2017 was XX percent, compared to 2013 water demands. With the Stage Three Drought declaration in effect and the need for a 30 percent reduction, the Water Conservation Program has continued its enhanced public information campaign of targeted outreach to specific user types, including: weekly messaging through social media, online news outlets, and industry contacts; presentations to community and industry groups; printed materials with drought messaging; targeted utility bill messaging; drought signage throughout the City; and additional training and workshops. Revenues Water revenues for Fiscal Year 2017, which includes August through November revenue, shows revenues are tracking closely with projections, with a positive variance of 3.4% or $640K. Rev. 011217 Council Agenda Report 6-a Drought Update and Annual Water Supply Management Report January 23, 2018 Page 4 Annual Water Supply Management Report The Water Supply Management Report (WSMR) is an annual report summarizing the activities of the past water year (October 1, 2016 through September 30, 2017). The report fulfills a mitigationDraft requirement of the Coastal Branch of the State Water Project to manage water supplies to prevent long-term overdraft of local groundwater. City staff also uses the report to inform Council and the public about recent activities and current water supply conditions. Key issues of the report are summarized below. Lake Cachuma ended the water year on September 30th at 45 percent of capacity. As the City’s largest water supply source, Lake Cachuma is the most important indicator of the City’s water supply status. Despite a handful of storms in January and February 2017, the last six water years (October 2011 - September 2017) represent one of the driest consecutive six year periods on record. Due to severe drought and low lake levels, the gravity fed conveyance system to receive water from Lake Cachuma was no longer operable when the lake level fell below the intake delivering water to the South Coast. The Cachuma Operation and Maintenance Board (COMB) was the lead agency responsible for construction of an Emergency Pump Project (EPP) to continue to convey critical water supply. The project included installation of 3,600 feet of pipeline and a pumping barge. The Cachuma EPP was in operation since August 2015, and the pumping barge was relocated to a deeper part of the lake in July 2016. When above average rainfall in Spring 2017 caused lake levels to increase, allowing gravity flow through the intake to resume, the EPP was demobilized and certain key components are now being leased should the temporary facility need to be re- deployed. COMB continues to monitor lake level projections and based on continued drought conditions, preliminary projections show a need for the pumping facility as early as 2019. COMB is also working on preliminary design of a potential permanent installation of the EPP pipelines to decrease risk of water supply outages, reduce long- term operating costs, and eliminate potential damage to facilities. In September 2016, the State Water Resources Control Board (SWRCB) released a long-awaited draft order amending the Bureau of Reclamation’s Water Rights for the Cachuma Project. Most notable of the draft order requirements is the release of additional flows downstream of Bradbury Dam, in addition to those required by the National Marine Fisheries Service’s 2000 Biological Opinion mandating minimum flow rates and other measures to prevent extinction of steelhead below Bradbury Dam. City staff worked with the Cachuma Conservation Release Board to prepare comments on the draft order, which were submitted on December 9, 2016.