13 - Laserfiche WebLink

In subsequent months, as the State's 2011 water supply status improved with several significant storm events in the winter and spring, DWR increased the allocation. By May 2011, DWR increased the allocation to 80 percent, as a result of above-average rainfall and snowfall which resulted in above-average Sierra snowpack. However, even with improved supply conditions, SWP deliveries will remain limited due to current and on- going restrictions in Delta pumping. DWR set the initial 2012 SWP allocation at 60% and just recently reduced that allocation to 50% (February 2012) as California is experiencing its lowest winter precipitation in the last 100 years. Based on past experience, it is likely that this allocation could drop even further through the summer of 2012. In 2006, prior to the Delta pumping restrictions of 2007, Zone 7 projected that it had sufficient supplies and storage capacity to meet full deliveries through build out of the adopted General Plans of the cities within its service area. However, recent and on- going reductions in Delta pumping and the potential supply reduction impacts of climate change have reduced Zone 7's sustainable water supply. On May 18, 2011 , Zone 7 staff presented its Annual Review of Sustainable Water Supply Report to the Zone 7 Board. The 2011 review compared projected water demands and available water supplies for the next five years and identified programs necessary to meet water demands. In response to these findings, Zone 7 has recently completed a detailed evaluation of Zone 7's water supplies that will make recommendations to help minimize near-term risks of water supply shortages while maximizing long-term flexibility until more information is known regarding a fix in the Delta. Zone 7's total water demands without additional water conservation are projected to increase by 3.7 percent between 2011 and 2015, while water demands for Zone 7's untreated customers are expected to remain constant. However, with the additional water conservation estimated by Zone 7 (and shared with the retailers), the projected water demands could remain relatively constant between 2011 and 2015 depending on the success of the regional water conservation efforts and compliance with SBx7-7 (California's requirement to reduce water use by 20% by 2020). Zone 7 has developed a water supply system consisting of imported surface water, local runoff, groundwater recharge activities, and non-local storage. This diverse water supply system allows Zone 7 to store excess water during average and wet years, and draw on these reserves during dry years to create a sustainable and reliable water supply for the Livermore-Amador Valley. Each year Zone 7 receives water supply from its water rights permit for diversions from Arroyo del Valle, and its contracts with DWR for SWP water, Byron Bethany Irrigation District (BBID), and DWR for Yuba Accord Water. The exact quantity of water supply available through these contracts is unknown at the beginning of the year because the yield depends on many factors, including local precipitation and snowfall in the Sierra. For planning-level purposes, Zone 7 staff estimates the projected yield from these water supplies at the beginning of the year, along with an estimate of the long-term average yield. Page 3 of 10