SOURCE: ACWA
CALIFORNIA, MARCH 18, 2016 -- March storms have significantly boosted some of the state’s reservoir levels, prompting the California Department of Water Resources to increase estimated water delivery allocations from the State Water Project to 45%, DWR officials announced.
The announcement is the third increase of the 2015-’16 water year. In December, DWR announced a 10% allocation and increased that estimate to 15% on Jan. 26. After storms increased the Sierra snowpack and brought significant rainfall to some drought-parched parts of the state, officials boosted the estimate a second time Feb. 24 to 30%.
Although February was mostly dry, rain and snow returned in March to boost the state’s two largest reservoirs – Shasta Lake and Lake Oroville – to slightly above their historic levels for the date. However, some key reservoirs, particularly in the southern part of the state, remain far below expected levels for this time of year.
Officials stressed in a press release that the drought has not ended despite the rains. California is on track to end the winter season with near-average conditions, but one such season does not compensate for four prior years of drought. Accurately predicting whether water year 2017 will be wet, dry, or average is beyond the skill of climate forecasters, and Californians must be prepared for the possibility of a dry 2017. Even with reservoir levels rising, conservation is the surest and easiest way to stretch supplies, officials said.
“February reminded us how quickly California’s weather can turn from wet to dry,” DWR Director Mark Cowin stated in a press release. “The lesson of this drought is that we all need to make daily conservation a way of life.”
March storms also will prevent DWR from needing to install a drought barrier this year to help control salinity in the Sacramento-San Joaquin Delta.
The U.S. Bureau of Reclamation, which operates California’s other major water project, the Central Valley Project, is expected to announce its initial allocation later this month.
Key reservoirs are rising from winter storms, but some remain below average for the date.
Here is some data on reservoirs as of early morning March 17: Lake Oroville in Butte County, was holding 2,708,486 acre-feet, 77% of its 3.5 million acre-foot capacity and 105% of its historical average for the date. Shasta Lake north of Redding, California’s and the CVP’s largest reservoir, was holding 3,850,207 acre-feet, 85% of its 4.5 million acre-foot capacity and 110% of its historical average. But San Luis Reservoir, a critical south-of-Delta pool for both the SWP and CVP, was holding only 990,970 acre-feet, 49% of its 2 million acre-foot capacity and just 55% of average storage for the date. Folsom Lake, a CVP reservoir near Sacramento, has risen to 70% of its 977,000 acre-foot capacity, 117% of historical average for the date, and has had to make flood control releases to retain space for heavy inflow.
Last year’s (2015) 20% SWP allocation was the second lowest since 1991, when agricultural customers of the SWP got a zero allocation and municipal customers received 30% of requests. In 2014, SWP deliveries were 5% of requested amounts for all customers. The last 100% allocation was in 2006. Seven of the nine years since 2007 have been dry.
SWP allocations in recent years include: 2015 – 20%; 2014 – 5%; 2013 – 35%; 2012 – 65%; 2011 – 80%; 2010 – 50%; 2009 – 40%; 2008 – 35%: 2007 – 60 percent; and 2006 – 100%
DWR’s California Data Exchange Center (CDEC) web sites show current water conditions at the state’s reservoirs and weather stations.
About ACWA
The Association of California Water Agencies (ACWA) is the largest statewide coalition of public water agencies in the country. Its 430 public agency members collectively are responsible for 90% of the water delivered to cities, farms and businesses in California.
