NEW PROJECT SOLICITATION: Colusa Subbasin Project and Management Actions Submittal Form
The Colusa Subbasin Groundwater Sustainability Agencies have re-opened the Colusa Subbasin Projects and Management Actions Submittal form. The purpose of this form is to gather ideas for potential projects and management actions (PMAs) that could be evaluated and possibly be included in the Colusa Subbasin Groundwater Sustainability Plan (GSP). The initial Colusa Subbasin GSP was submitted in January 2022 and contains PMAs that were submitted during the GSP development process. Now that the GSP has been submitted and we are looking toward implementation, the GSAs have re-opened the PMA Submittal Form to collect additional suggestions and ideas to help the Colusa Subbasin reach and maintain sustainability.
Potential PMAs may fall under several categories, including but not limited to the following:
• Recharge projects
• Supply augmentation projects
• Water conservation projects
• Projects to reduce non-beneficial consumptive use
• Groundwater pumping allocations
• Monitoring programs (groundwater pumping, water levels, stream flows, etc.)
Projects submittals can be made through this online form: Colusa Subbasin GSP Projects and Management Actions (PMAs) Submittal Form (arcgis.com). Or, download and complete this form and email it to CThomasKeefer@rgs.ca.gov.
Deadline for project submittals to be considered in the current GSP project prioritization process is 5:00 p.m. on Thursday, September 8, 2022.
Groundwater Sustainability Plans (GSP)
Visit the Groundwater Sustainability Plan (GSP) page for information on GSP development in the Colusa Subbasin and surrounding basins. GSP development began in summer, 2018. Local Plans are due January 31, 2022. It is important that Stakeholders are involved in the GSP development process.
Well Monitoring Pilot Program Round 2
The Colusa Groundwater Authority (CGA) and the Glenn Groundwater Authority (GGA) are launching Round 2 of our Well Monitoring Pilot Program as part of Groundwater Sustainability Plan efforts in the Colusa Subbasin. This voluntary, non-regulatory program will gather information about groundwater use in the Colusa Subbasin.
Colusa Subbasin Well Monitoring Pilot Program Flyer
Hydrogeologic Conceptual Model and Water Budget for the Colusa Subbasin
Water budgets are a first step to understanding local conditions and determining if basins are sustainable, and part of the Basin Settings chapter of Groundwater Sustainability Plans. The Colusa Groundwater Authority (CGA) and Glenn Groundwater Authority (GGA) are working together to complete this project which will be the foundation for GSP development in the Colusa Subbasin.
Multi-benefit On-farm Managed Aquifer Recharge Program
The Nature Conservancy, in partnership with the Colusa Groundwater Authority, is now accepting online applications for an on-farm Multi-Benefit Groundwater Recharge Incentive Program for Fall 2020. This program provides an opportunity for growers in specified areas in Colusa County to receive financial compensation for recharging groundwater in the course of normal farming operations while also providing critical shallow wetland habitat for migratory birds.
The application for this program consists of a one-page form and will require a map and a crop history from the last 10 years for the proposed field(s). At the end of the application, click the Review button and be sure to click “Confirm” on the review page to submit the application. We encourage early submissions. The application is available on the TNC website: Colusa Multi-Benefit Groundwater Recharge Program.
For more information, click HERE to view the program flyer.
A landowner workshop about this program was held at Colusa Industrial Properties on February 26, 2020 at Colusa Industrial Properties.
The Nature Conservancy (TNC) received funding from the Sustainable Groundwater Planning Grant Program for a Multi-benefit On-farm Managed Aquifer Recharge Project in portions of the Colusa and Butte Subbasins in Colusa County. The CGA is coordinating with TNC on this project. The original scope of work focused on an area in the north east portion of Colusa County. In September, 2018, TNC received approval from DWR to expand this project area to include farm land on the west side of the Colusa Subbasin near the towns of Arbuckle and Williams.
Basin Boundary Modifications
The CGA submitted a successful request to DWR for a Basin Boundary Modification (BBM) in September, 2018. Please see the Basin Boundary Modifications Page for information.
OpenET Project
A subcommittee of the Colusa Groundwater Authority is coordinating with the Environmental Defense Fund on their project called OpenET. The goal of the project is to make critical evapotranspiration (ET) information easily accessible to everyone who needs it across the western United States through a broadly accessible web-based platform – OpenET. For more information on the project, visit the website: www.etdata.org
Completed Work
(Click on the links to view/download the studies)
- 2017-18 Sacramento Valley GPS Land Subsidence Survey, California Department of Water Resources
The California Department of Water Resources (DWR) Northern Region Office, in cooperation with several local agencies, completed a Sacramento Valley-wide GPS land subsidence survey in summer, 2017. Results of this survey were released in February, 2019.The results of this survey are consistent with the 2016 Limited survey in the Area of Interest in Colusa County and showed a maximum decrease in land surface elevation of -2.14′ at one monument in the Arbuckle area. This activity occurred some time between 2008 when DWR completed a baseline survey, and 2016, during the most extreme drought in California. More data will be needed to understand the extent and causes of land subsidence in this area and if this is inelastic (permanent) or elastic (recoverable) subsidence. The full report can be downloaded on the DWR website here:
https://water.ca.gov/News/News-Releases/2019/January/Survey-Shows-Areas-of-Land-Subsidence - Colusa County Groundwater Assessment (2016)
- Limited GPS land subsidence survey in the Area of Interest (2016)
- Colusa County SGMA Risk Assessment (2016)
- Proposition 1 Sustainable Groundwater Planning grant for Counties with Stressed Basins (2016-2018)
A Program to Advance Groundwater Sustainability for Colusa County through Policy, Institutional and Technical Refinement
Financed Under: The Water Quality, Supply, and Infrastructure Improvement Act of 2014, Sustainable Groundwater Planning Grant Program (Proposition 1)
Administered by: The State of California Department of Water Resources
Contractor: Davids Egineering, Inc.
The County of Colusa received $250,000 in grant funding in 2016 from the Sustainable Groundwater Planning Grant Program for Counties with Stressed Basins. The Work Plan includes a groundwater monitoring network update and development of a data management system. This project was completed in June, 2018, and much of the work will be integrated into the Colusa Subbasin Groundwater Sustainability Plan.