Sacramento Valley – Yolo

2003: Bulletin 118 basin description

2014: CASGEM basin prioritization – high. Comment: Localized TDS problems preclude using GW for some M&I uses without treatment. Some subsidence in northeast of Davis and in northern Yolo. GW Use based on Yolo County, California’s Water Supply System: Conjunctive Use Without Management, UC Davis, 1992

2016: Basin boundary modification with  Colusa 5-021.52, Capay  5-021.68, and Solano 5-021.66 subbasins  

Revised basin boundary description

2018: Draft basin prioritization – high. Groundwater levels and subsidence comments:

• 1) CASGEM/WDL/GWIDS: Longterm hydrographs show groundwater level decline. Source: DWR 2) The areas of continuing overdraft in the County cover most of the Lower Cache-Putah and western Colusa sub-basins. To some extent improvements from reduced pumping have occurred in the DWD area of Colusa sub-basin. Particular overdraft spots include the Yolo-Woodland area on both sides of Cache Creek, areas between Zamora and Yolo, and areas to the northeast of Davis. These areas coincide with places where subsidence and/or deteriorating groundwater quality have been measured. Source: Yolo County, California’s Water Supply System: Conjunctive Use without Management, UC Davis, 1992
• 1) Zamora Land Subsidence Extensometer (11N01E24Q008M), Conaway Extensometer (09N03E08C004M), DWR Water Data Resources;  JPL/ NASA Caltech report 2015-16

Groundwater-related transfer “Type A” in which local groundwater is pumped to compensate for water exports.

2019: Basin boundary modification. Phase 2 draft priority: high

2022: January 28 – Groundwater Sustainability Plan submitted to Department of Water Resources (DWR)

2023: October 26 – GSP approved by DWR