The project team presented several updates to the Groundwater Sustainability Commission (GSC) on March 11, 2020 including a summary of Chapter 5 of the GSP, Groundwater Conditions. Chapter 5 documents the current and historical groundwater conditions of the SLO Basin and includes: groundwater elevation contour maps; estimates of groundwater in storage; groundwater quality distribution; history of land subsidence; as well as the identification of interconnected groundwater-surface water features and groundwater dependent ecosystems. In the meeting, the GSC recommended that Chapter 5 be received by the GSA and released for public comment. The chapter was opened for public comment on March 11, 2020 and closed on May 31, 2020. View Chapter 5 and submitted comments.
The project team also gave an overview of the process they’ll use to develop a basin wide sustainability goal and corresponding monitoring network for the SLO Basin. The presentation included an overview of the sustainability indicators required by SGMA. Each representative monitoring well will identify a measurable objective and minimum threshold for each of the sustainability indicators. The sustainability indicators include: 1) chronic lowering of groundwater levels, 2) reduction of groundwater in storage, 3) land subsidence, 4) water quality degradation, and 5) interconnected surface water depletions.
The project team also defined key concepts associated with the Basin monitoring network, including: potential management areas, undesirable results, measurable objectives, minimum thresholds, interim milestones and representative monitoring sites. The team confirmed that the June stakeholder workshop as well as the July and September GSC Meetings would gather input to inform a draft of the basin wide Sustainability Goal.
The project team has been tasked with the development of an integrated groundwater/surface water flow model (GW/SW Model) for use in supporting the GSP development. The model will be used to estimate future groundwater levels in the basin, and to demonstrate the effects that various proposed projects and management actions will have on the goal of achieving sustainability by 2042. At the meeting, the project team provided an update on the progress of the GW/SW Model and the next steps in the model development, which will include model calibration and sensitivity analysis. The Technical Memo: Surface Water / Groundwater Modeling Approach opened for public comment following the GSC meeting and closed on June 15, 2020. View the Technical Memo and submitted comments.