Subsidence and Groundwater Monitoring Project

The California Department of Water Resources (DWR) is installing equipment to collect spatial information at 5 groundwater and subsidence monitoring stations along the California Aqueduct (Aqueduct) in Kern County.

Subsidence or sinking of the land surface primarily due to overdraft of groundwater in the San Joaquin Valley has occurred along the Aqueduct over the last century. In the area of this project, subsidence of up to approximately 5 feet has occurred during the decades after construction in 1967. This subsidence has reduced the SWP’s delivery capability and reliability, as well as increased maintenance, repair, and energy costs for the Aqueduct. The project instrumentation delivers real-time data to monitor groundwater levels and other spatial information, which helps inform how subsidence is affecting the Aqueduct and assists in maintaining the SWP infrastructure.

The project involves drilling below the ground surface within the existing Aqueduct right-of-way to depths between 25 to 2,800 feet below the ground surface, and diameters between 6 to approximately 24 inches. Depths and diameters of drill holes will be based on the infrastructure installed (i.e., monitoring well, extensometer, or continuous global positioning system station). The groundwater and subsidence monitoring stations would be installed approximately at Aqueduct Mile Posts (MP) 213.0L, 230.6L, 259.6L, 271.2L, and 279.1L within the DWR Operations and Maintenance San Joaquin Field Division in Kern County. The northern most monitoring station (MP 213.0L) is approximately 8 miles south of the town of Lost Hills. The southern most monitoring station (MP279.1L) is located approximately 3 miles southwest of the town of Mettler.

Project Location Map: