Groundwater Management

Groundwater is one of Lake County’s greatest natural resources. In an average year, groundwater meets about 60 percent of Lake County’s urban and agricultural water demands. The demand for water will increase significantly as Lake County’s population grows and agricultural production increases. Urban water demand is anticipated to increase from an average of 10,900 acre-feet per year to 19,738 acre-feet per year by the year 2040, an 81% increase. Depending on the type an rate of agricultural development, the current average agricultural water demand of 39,817 acre-feet per year may be minimal or as much as 48,387 acre-feet per year by the year 2040, a 21% increase. Additional information on water demand projections are available below.
Lake County Water Demand Forecast

With the exception of areas near Clear Lake, nearly all the additional water demand is likely to be supplied by groundwater. In many basins, our ability to optimally use groundwater is affected by overdraft and water quality impacts, or limited by a lack of data, management, and coordination between water users.

Effective management of groundwater basins is essential because groundwater will play a key role in meeting Lake County’s water needs. Lake County is committed to implementing effective, locally planned and controlled groundwater management programs. Lake County is also committed to partnerships with local agencies to coordinate and expand data monitoring activities that will provide necessary information for more effective groundwater management. Coordinated data collection at all levels and local planning and management will help to ensure that groundwater continues to serve the needs of Californians.

Locally led groundwater management planning is an effective way of managing our groundwater for the future. Groundwater management plans could include such possible components as monitoring of groundwater levels in storage; mitigation of conditions of overdraft; replenishment of ground-water extracted by water producers; facilitation of conjunctive use operations; administration of a well abandonment and well destruction program; identification of well construction policies; construction and operation of groundwater contamination, clean-up, recharge storage, conservation, water recycling, and extraction projects; development of relationships with state and federal regulatory agencies; review of land-use plans to assess activities which could create a risk of groundwater contamination; or reductions in the amount of water pumped from specific wells.

In response to these concerns, the Lake County Watershed Protection District led the development and adoption of the Big Valley Groundwater Management Plan in 1999 and the Lake County Groundwater Management Plan in 2006. The Plans and supporting documentation are available below.

Big Valley Groundwater Management Plan Adopting Resolution

Big Valley Groundwater Management Plan

Lake County Water Inventory and Analysis

Lake County Groundwater Management Plan Adopting Resolution

Lake County Groundwater Management Plan

If you have questions, please contact the Lake County Water Resources Department at 707-263-2344.

Updated October 9, 2014