Healthy reservoir storage levels, strong regional water conservation efforts and growing water transfers from the Colorado River mean San Diego County will have sufficient water supplies for 2014 even if dry conditions persist. That assessment was presented Thursday by the San Diego County Water Authority staff to the Board of Directors.
The past two years have been dry across California, and 11 of the past 14 years have been dry in the Colorado River Basin. Locally, precipitation at Lindbergh Field was 63 percent of normal between Oct. 1, 2012, and Sept. 30, 2013.
A third year with limited rain and snow would draw down several key reservoirs going into 2015, but for now the Water Authority is not anticipating the need for extraordinary conservation measures or water shortage allocations in 2014. The Water Authority will closely monitor winter weather, particularly in the Sierra Nevada and the Rocky Mountains, where the bulk of the San Diego region’s water supplies originate. The National Weather Service is giving equal chances for wet, dry and normal conditions over the next three months. About 75 percent of the state’s average annual precipitation falls between November and March.
“Because dry spells are part of living in California, our region has invested heavily in infrastructure, conservation and new water supplies to protect our economy and quality of life,” said Thomas V. Wornham, chair of the Water Authority’s Board of Directors. “We are in better shape than we were two years into the last drought, but we still need to practice smart water use no matter the weather.”
The Water Authority’s largest supplier of water – the Los Angeles-based Metropolitan Water District of Southern California – recently said it has adequate reserves and doesn’t expect to impose allocations in 2014, even though imports from the State Water Project are expected to be very low due to poor hydrological conditions and regulatory restrictions. At the start of 2013, MWD had about 2.7 million acre-feet of water storage reserves, not counting more than 600,000 acre-feet of emergency storage. It expects to withdraw up to 500,000 acre-feet from storage to meet demands by the end of 2013. That will leave MWD with at least 2.2 million acre-feet of storage reserves, about 20 percent more than it had when the last drought began in 2007. (An acre-foot is approximately 325,900 gallons, or roughly enough to serve two typical families of four for a year.)
The Water Authority and its 24 member agencies have also invested in additional shortage management strategies and diversifying San Diego County’s water supply sources. Those include adopting water use-efficiency programs, and developing new local supplies such as groundwater and water recycling.
A significant hedge against drought for San Diego County is the conservation-and-transfer programs that are part of the Colorado River Quantification Settlement Agreement of 2003. In 2014, these transfers will provide San Diego County with approximately 180,000 acre-feet of Colorado River water that isn’t subject to shortage allocations from MWD. The Water Authority’s independent Colorado River transfers ramp up to 280,000 acre-feet in 2021, enough to support more than a half-million typical single-family homes.
In addition, the Water Authority in November 2012 signed an agreement to buy up to 56,000 acre-feet of water annually from the Carlsbad Desalination Project, which is under construction and expected to start commercial production in 2016. Over the past decade, the Water Authority also developed its $1.5 billion Emergency Storage Program, including the expansion of San Vicente Reservoir to store more water locally for use during dry years and emergencies. The San Vicente Dam Raise is nearly complete, and the reservoir is expected to fill over the next few years, depending on water availability.
More efficient regional water use is another major component of balancing supply and demand. Per capita water use in San Diego County dropped by about 30 percent between 2007 and 2012 due to several factors, including widespread adoption of conservation strategies. While regional water consumption increased by about 6 percent in fiscal year 2013 compared to the year before, the San Diego region is on track to achieve state-mandated conservation goals by 2020.
“County residents have really embraced a water-wise mentality,” said Ken Weinberg, director of water resources for the Water Authority. “When you add that to our growing independent water supplies from the Colorado River, increasing local supplies and solid amounts of reservoir storage in Southern California, we are well prepared for 2014. Nevertheless, we will carefully assess supply and demand in coming months to ensure we can adjust to changing conditions.”
The Water Authority also is assessing proposed solutions to water supply issues in the Sacramento-San Joaquin Bay-Delta, the hub of the state’s water supply system and the source of about 20 percent of the San Diego region’s water supplies. It has become less reliable as a supply source in recent years and its habitat has deteriorated. The Water Authority’s Board of Directors is analyzing potential strategies for restoring the Bay-Delta by seeking solutions that are cost-effective and correctly sized – and can secure long-term financing. In 2014, the Board is expected to consider an official comment letter on environmental documents related to the Bay Delta Conservation Plan, and it may also adopt a position on one or more project proposals. For more information about the Bay-Delta, go to www.sdcwa.org/bay-delta-conservation-plan.
For more information about water supply and demand, go to page 42 of the Board packet at www.sdcwa.org/sites/default/files/files/board/2013_agendas/2013_10_24_BoardPacket.pdf.