Water supply from Carlsbad Desalination Plant certified as Drought-Resilient

County water ratepayers benefit from investment through easing of state’s water-use mandates.

Mar 10th, 2016

Carlsbad, Ca., March 10, 2016 --State regulators have certified the supply of potable water from the Claude “Bud” Lewis Carlsbad Desalination Plant as drought-resilient, reducing the regional impacts of emergency water-use mandates the state imposed in June 2015. Certification by the State Water Resources Control Board lowers the regional aggregate water conservation goal from 20 percent to about 13 percent, though water-use targets will continue to vary by local water agency.

On Feb. 2, the State Board extended mandatory conservation measures for water agencies statewide through October and said it would reconsider the regulations after assessing reservoir levels as well as snowpack and regional water supply conditions in April. The State Board also approved supply credits toward meeting conservation targets for agencies that have developed local, drought-resilient supplies since 2013.

The San Diego County Water Authority has worked closely with the state in recent months to ensure that local member agencies will benefit from investments in the nation’s largest seawater desalination plant, which opened in December and produces about 50 million gallons per day of high-quality, drought-proof water that reduces the region’s reliance on other water sources. The Water Authority and its member agencies will continue to work with the State Board to refine the draft conservation standards issued today.

“The state’s approval of local supply credits means that our local communities’ investments in drought-resilient water supplies will be rewarded during dry periods, and reinforces our region’s supply diversification strategy to improve water reliability,” said Mark Weston, chair of the Water Authority’s Board of Directors.

“This formal acknowledgment of our investments provides welcome relief from some of the unintended negative consequences of the state’s emergency water-use mandates. It will allow more residents to replace their lawns with WaterSmart landscapes, and provides businesses room to expand while continuing to use water efficiently – but we must continue to embrace our duty to conserve water during these unprecedented drought conditions.”

Water-use efficiency is still critical because the state is in its fifth year of drought, and no one knows how long hot and dry conditions will last. Record-breaking high temperatures in February, combined with very little rain, put significant upward pressure on water use, underscoring the value of the region’s water supply diversification plan that includes drought-resilient supplies such as desalinated seawater.

Despite El Niño conditions, snowpack is below average in key parts of the state, including the northern Sierra Nevada. However, precipitation is expected during the next week, and state law requires that irrigation systems remain off during storms and for 48 hours afterward.

The Water Authority’s Board is expected to consider updated drought-response actions later this month, based on a variety of factors, including local water supplies, further modifications to the state’s water-use regulation and water deliveries from the Metropolitan Water District of Southern California.

Since June 2015, Water Authority member agencies have been under state mandates to reduce water use by 12 to 36 percent compared to 2013 levels, with a regional aggregate target of 20 percent. From June 2015 through January, the San Diego region reduced potable water use by 23 percent compared to the same months in 2013. Conserved water has been stored in the recently expanded San Vicente Reservoir.

The Water Authority has advocated for state emergency water-use mandates to account for local supply conditions instead of treating all regions of the state as if they’re facing the same level of water-use emergency. In San Diego County, a long-term water supply diversification plan launched after the drought of 1987-92 means the region, even as it faces a potential fifth year of drought, has enough water to meet 99 percent of normal demands this fiscal year. The initial state water-use regulation prevented San Diego County ratepayers from getting the benefit of the water supply investments they made. Local residents and businesses joined the Water Authority’s call for a more equitable and sustainable approach, which the State Board began to acknowledge in its revised regulation approved on Feb. 2.

Under the draft state figures released today, certification of the Carlsbad desalinated supplies reduces each local agency’s water-savings target by up to 8 percentage points. However, the modified emergency regulation still requires that every local water agency reduce water use compared to 2013 baseline levels to ensure conservation continues during this drought emergency. The minimum water-use reduction is 8 percent compared to baseline levels, but most agencies in the San Diego region will still need to meet higher savings targets. For a comparison of local water agencies’ initial and draft revised targets, along with more information about the modified state regulations, go to www.sdcwa.org/state-board-regulations.

The State Board may make additional adjustments to its water-use mandate based on how El Niño conditions affect state and local water supplies over the next several months. While the Sierra snowpack is better than in recent years, it would need to be around 150 percent of normal for the state to emerge from the drought, according to officials at the California Department of Water Resources.

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