Location:Colusa Subbasin, Colusa and Glenn Counties
Date:2016 - 2022
In 2016, the team led by Davids Engineering was contracted to support Colusa and Glenn Counties in SGMA compliance efforts for the subbasins underlying portions of each county, including the Colusa Subbasin. Through funding from a Proposition 1 SGMA Stressed Basin Grant, our team began laying the technical foundation for Groundwater Sustainability Plans (GSPs) by:
•Completing a detailed review of high-priority data available for establishing the Basin Setting
•Identifying potential data management platforms and groundwater models, and
•Developing initial subbasin water budgets and a preliminary Hydrogeologic Conceptual Model (HCM).
From 2019-2022, our team led the development of a coordinated GSP covering the entire Colusa Subbasin. GSP development seamlessly built upon prior efforts to describe foundational components of the Basin Setting, including the HCM, past and current groundwater conditions, and water budgets to evaluate water supplies and uses in the Colusa Subbasin. Our team also embarked on new efforts to develop sustainable management criteria, monitoring networks for evaluating groundwater conditions during GSP implementation, and projects and management actions to ensure the ongoing sustainability of groundwater conditions in the Colusa Subbasin.
GSP development efforts followed several key guiding principles:
•The processes for developing and implementing the GSP must be iterative and adaptive to achieve sustainability for all beneficial groundwater users while also balancing the needs of local communities and the local economy.
•GSP decisions must consider both social and technical information, including both qualitative and quantitative factors affecting all users.
In this spirit, the Davids Engineering team led GSP development to ensure regulatory compliance with SGMA and provide a foundation to achieve and maintain sustainability of the Subbasin’s groundwater resources while also maintaining and enhancing local communities, the economy, and the environment. These efforts culminated in the completion and submittal of a SGMA-compliant GSP in January 2022.