The Department of Water Resources (DWR) today released a report on groundwater showing that throughout California groundwater resources are at historically low levels. Directed by Governor Edmund G Brown Jr.’s emergency drought declaration in January, the report details basins with potential water shortages and gaps in groundwater monitoring. This report will form the basis for future actions to address current gaps in monitoring and oversight of groundwater resources.
“Millions of Californians rely on groundwater every day,” said DWR Director Mark Cowin. “Being good stewards of our groundwater basins is essential for ensuring that we can turn to them during dry years when these resources are critically needed.”
Since spring 2008, groundwater levels have experienced record historical lows in most areas of the state and especially in the northern portion of the San Francisco Bay Hydrologic region, the southern San Joaquin Valley, and also the South Lahontan and South Coast hydrologic regions. In many areas of the San Joaquin Valley, recent groundwater levels are more than 100 feet below previous historical lows.
Thirty-six alluvial groundwater basins throughout the state have a high degree of groundwater use and reliance may possess greater potential to incur water shortages as a result of drought. The basins exist in the North Coast, Central Coast, Sacramento River, Tulare Lake, and South Coast hydrologic regions.
Key findings of the report include:
Groundwater levels have decreased in nearly all areas of the state since spring 2013, and more notably since spring 2010.
The greatest concentration of recently deepened wells is in the fractured bedrock foothill areas of Nevada, Placer, and El Dorado counties.
The Kaweah and Kings sub basins have the greatest numbers of deepened wells in an alluvial groundwater basin.
Of California’s 515 alluvial groundwater basins, 169 are fully or partially monitored under the California Statewide Groundwater Elevation Monitoring (CASGEM) program as of April 15, 2014.
Forty of 126 High and Medium priority basins are not monitored under CASGEM as of April 15, 2014. There are significant CASGEM groundwater monitoring data gaps in the Sacramento, San Joaquin River, Tulare Lake, Central Coast, and South Lahontan hydrologic regions.
Several areas of the state lack a current groundwater management plan that addresses all related requirements of the California Water Code.
The report is available at www.water.ca.gov/waterconditions, and as directed by Governor Brown’s April 25th Executive Order, DWR will update this report later this year.
The report is a compilation of information available from existing sources, such as DWR’s draft California Water Plan Update 2013, and from existing groundwater monitoring programs. Presented together, these data provide a compelling picture of the status of California groundwater and groundwater monitoring conditions. In an average water year, groundwater supports about 40 percent of the state’s urban and agricultural water uses. Reliance on groundwater increases dramatically when drought causes shortages in surface water supplies.
Present dry conditions have exacerbated long-standing management issues in basins having a high reliance on groundwater, highlighting the need for long-term sustainable management of California’s groundwater.
The California Water Action Plan developed by the Natural Resources Agency, California Environmental Protection Agency and Department of Food and Agriculture identifies improving groundwater management as a key priority. The Plan expresses the Governor’s commitment to work with the Legislature and ensure that local agencies have the tools and authority needed for sustainable management of groundwater resources. The Governor’s 2014-15 budget proposed $618.7 million for funding various actions in the Plan, including support for improved groundwater management. Much of that funding as well as additional funding for drought response and groundwater assistance was accelerated as part of the emergency drought legislation signed by the Governor in March.
“We must work together to control groundwater overdraft to avoid impacts such as land subsidence, seawater intrusion, and migration of poor quality water”, said Director Cowin.
As directed by the January drought emergency declaration, DWR is working to update monitoring of land subsidence in the Central Valley. DWR has also been working with county agencies to ensure that water well drillers submit required well logs for newly constructed and deepened wells in a timely manner to facilitate tracking of areas that are experiencing drought-related groundwater problems.
Governor Brown has called on all Californians to reduce their water use by 20 percent – visit SaveOurH2O.org to find out how everyone can do their part, and visit Drought.CA.Gov to learn more about how California is dealing with the effects of the drought.