By Mary Fahey
Colusa County Water Resources Manager
These are historic times for groundwater management in California, with the onset of the Sustainable Groundwater Management Act (SGMA), and recent extreme drought conditions that were followed by one of the wettest winters on record.
Prior to this last winter, a ten year stretch of generally dry conditions existed in the Sacramento Valley, creating many challenges for water managers. Challenges, yes, but these extreme conditions have also provided an excellent opportunity to evaluate the resiliency of the groundwater system.
In Colusa County, groundwater conditions are generally good, however groundwater levels in the southwest portion of the County were drawn down considerably during the drought, which is not surprising. This area of the County is ideal for growing tree crops, but it is also an area where surface water supplies were cut back several years, including a 0% allocation in 2014 for the first time in history, and again in 2015.
Despite these challenges, 2017 groundwater levels in Colusa County are showing good recovery over 2016 levels after last year’s wet winter. This is illustrated on DWR’s groundwater level change map below.
As we move into the era of SGMA, The Colusa Groundwater Authority, which will be implementing SGMA in Colusa County, will be coordinating with other Groundwater Sustainability Agencies to plan and implement projects and programs that will preserve and enhance sustainable groundwater conditions locally.