Groundwater Management

The Sustainable Groundwater Management Act (SGMA) established a new structure for managing California’s groundwater resources at a local level by local agencies. SGMA requires, by June 30, 2017, the formation of locally-controlled groundwater sustainability agencies (GSAs) in the State’s high- and medium-priority groundwater basins and subbasins (basins). A GSA is responsible for developing and implementing a groundwater sustainability plan (GSP) to meet the sustainability goal of the basin to ensure that it is operated within its sustainable yield, without causing undesirable results. The GSP Emergency Regulations for evaluating GSPs, the implementation of GSPs, and coordination agreements were adopted by DWR and approved by the California Water Commission on May 18, 2016.

County’s Role in GSA Formation
The legislative intent of SGMA is to recognize and preserve the authority of cities and counties to manage groundwater pursuant to their existing powers. As such, local governments play an important land use and water management role in California and should be involved in GSA formation and GSP implementation.

• In the event that there is an area within a high- or medium-priority basin that is not within the management area of a GSA, the county within which that unmanaged area lies will be presumed to be the GSA for that area. (Water Code § 10724(a))
• A county shall provide notification to DWR of its intent to manage the unmanaged area pursuant to Water Code §10723.8 unless the county notifies DWR in writing that it will not be the GSA for the area. (Water Code § 10724(b))
• Domestic Well Users and SGMA - Click here for a handout from the State Water Board that should answer many questions that domestic well owners have about SGMA. 

There are 515 alluvial groundwater basins and subbasins in California as defined in DWR's Bulletin 118. These basins contribute close to 40 percent of California's annual water supply in an average year and as much as 45 percent in dry years. During extensive dry or drought years, groundwater can provide close to 60 percent of the water supply. Statewide, approximately 30 million people, or 80 percent of Californians, live in areas overlying alluvial groundwater basins. Some communities are 100 percent reliant on groundwater.

The California Department of Water Resources (DWR) implemented the California Statewide Groundwater Elevation Monitoring (CASGEM) Program in response to legislation enacted in California's 2009 Comprehensive Water package. As part of the CASGEM Program and pursuant to the California Water Code (CWC §10933), DWR is required to prioritize California groundwater basins, so as to help identify, evaluate, and determine the need for additional groundwater level monitoring.

The CWC requires a statewide prioritization of California's groundwater basins using the following eight criteria:

1. Overlying population;
2. The projected growth of the overlying population;
3. Public supply wells;
4. Total wells;
5. Overlying irrigated acreage;
6. Reliance on groundwater as the primary source of water;
7. Impacts on the groundwater; including overdraft, subsidence, saline intrusion, and other water quality degradation; and
8. Any other information determined to be relevant by the Department.

Click Here to download the CASGEM Brochure 

The CASGEM Groundwater Basin Prioritization (Basin Prioritization) is a statewide ranking of groundwater basin importance that incorporates groundwater reliance and focuses on basins producing greater than 90% of California's annual groundwater. Although the results are a statewide assessment; it is important to recognize the statewide findings are not intended to diminish the local importance of groundwater including in the smaller size or lower-use groundwater basins.

The Modoc County Board of Supervisors established a Groundwater Resources Advisory Committee to provided local input into the process of implementing SGMA. The Groundwater Resources Advisory Committee meets on the fourth Thursday of every month beginning in February of each year, except for December, when the meeting shall be held on the second Thursday.

For GRAC agenda and information regarding the meetings CLICK HERE

Modoc County Medium Priority Basins
Basin Name: KLAMATH RIVER VALLEY
Subbasin Name: TULELAKE
For more information on the Tulelake Subbasin or to access the agendas and minutes of the Tulelake Core Team, CLICK HERE.

Basin Name: BIG VALLEY
For more information on the Big Valley Groundwater Basin or to access the agendas and minutes of the Big Valley Advisory Committee CLICK HERE.

Modoc County Low or Very Low Priority Basins

Basin Name: SURPRISE VALLEY, COW HEAD LAKE VALLEY, GOOSE LAKE (GOOSE VALLEY), GOOSE LAKE (FANDANGO VALLEY), JOSEPH CREEK, ALTURAS AREA (SOUTH FORK PITT RIVER), JESS VALLEY, LONG VALLEY, ROCK PRAIRIE VALLEY, WARM SPRINGS VALLEY, FAIRCHILD SWAMP VALLEY, ROUND VALLEY, EGG LAKE VALLEY, HOT SPRINGS VALLEY