Comparing domestic and public-supply groundwater quality in the northern San Joaquin Valley, 2019—California GAMA Priority Basin Project

U.S. Geological Survey (USGS) | June 5th, 2023

Groundwater quality in the Northern San Joaquin Valley region of California was studied as part of California State Water Resources Control Board (SWRCB) Groundwater Ambi

Groundwater quality in the Northern San Joaquin Valley region of California was studied as part of California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment Program-Priority Basin Project (GAMA-PBP). The GAMA-PBP made a spatially unbiased assessment of the aquifer system used for domestic drinking-water supply in the study region and compared the results to the aquifer system used for public drinking-water supply. These assessments characterized the quality of raw groundwater to evaluate ambient conditions in regional aquifers and not the quality of treated drinking water. The study included two components: (1) a status assessment presenting study results summarizing the status of groundwater quality used for domestic supply in the Northern San Joaquin Valley and (2) a comparative assessment of groundwater resources used for domestic and public drinking-water supply in the study region.

Conduct Airborne Electromagnetic Surveys

California Department of Water Resources (DWR) | July 15th, 2020

Cover cropping and no-tillage improve soil health in an arid irrigated cropping system in California’s San Joaquin Valley, USA

Soil and Tillage Research (Elsevier) | January 3rd, 2017

The concept of soil health has attracted considerable attention during the past two decades, but few studies have focused on the effects on soil health of long-term soil

The concept of soil health has attracted considerable attention during the past two decades, but few studies have focused on the effects on soil health of long-term soil management in arid irrigated environments. We investigated the effects of cover cropping and no-till management on soil physical and chemical properties during a 15-year experiment in California’s San Joaquin Valley (SJV) USA. Our objective was to determine if soil health could be improved by these practices in an annual crop rotation. The impact of long-term no-tillage (NT) and cover cropping (CC) practices, alone and in combination, was measured and compared with standard tillage (ST) with and without cover crops (NO) in irrigated row crops after 15 years of management. Soil aggregation, rates of water infiltration, content of carbon, nitrogen, water extractable organic carbon (WEOC) and organic nitrogen (WEON), residue cover, and biological activity were all increased by NT and CC practices relative to STNO. However, effects varied by depth with NT increasing soil bulk density by 12% in the 0–15 cm depth and 10% in the 15–30 cm depth. Higher levels of WEOC were found in the CC surface (0–5 cm) depth in both spring and fall samplings in 2014. Surface layer (0–15 cm) WEON was higher in the CC systems for both samplings. Tillage did not affect WEON in the spring, but WEON was increased in the NT surface soil layer in the fall. Sampling depth, CC, and tillage affected 1-day soil respiration and a soil health index assessment, however the effects were seasonal, with higher levels found in the fall sampling than in the spring. Both respiration and the soil health index were increased by CC with higher levels found in the 0–5 cm depth than in the 5–15 and 15–30 cm depths. Results indicated that adoption of NT and CC in arid, irrigated cropping systems could benefit soil health by improving chemical, physical, and biological indicators of soil functions while maintaining similar crop yields as the ST system.

CV SALTS Prioritization & Optimization Study Year 1 Progress Report

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | March 24th, 2023

CV-SALTS Groundwater Sustainability Plan Data Collection - Pilot Study Results

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | February 1st, 2024

The purpose of Prioritization & Optimization (P&O) Study Task 5.3 (Information Extraction from Groundwater Sustainability Plans [GSP]) is to extract and organize relevan

The purpose of Prioritization & Optimization (P&O) Study Task 5.3 (Information Extraction from Groundwater Sustainability Plans [GSP]) is to extract and organize relevant GSP data and information that can be used to (1) validate or refine information contained in the P&O Study’s CV-SWAT watershed model (developed to support ongoing baseline characterization work); (2) support the eventual development of salinity management alternatives within specified planning areas; and (3) help ensure that long-term Central Valley salt planning considers ongoing Groundwater Sustainability Agency (GSA) planning efforts, which is of particular interest to the State Water Resources Control Board.

CV-SALTS Groundwater Sustainability Plan Data Integration Report Integrated Scope of Work - Task 5.3 (Draft)

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | June 20th, 2024

The purpose of Prioritization & Optimization (P&O) Study Task 5.3 (Information Extraction from Groundwater Sustainability Plans [GSP]) is to extract and organize

The purpose of Prioritization & Optimization (P&O) Study Task 5.3 (Information Extraction from Groundwater Sustainability Plans [GSP]) is to extract and organize relevant GSP data and information that can be used to: Validate or refine information contained in the P&O Study’s Central Valley Soil and Water Assessment Tool (CV-SWAT) watershed model and other models (developed to support ongoing baseline characterization work and future salinity-related analyses); Support the eventual development of salinity management alternatives within specified Central Valley planning areas; and Help ensure that long-term Central Valley salt planning understands and considers ongoing Groundwater Sustainability Agency (GSA) planning efforts, efforts and potential future conditions of the water in the Central Valley region and benefits from the local investment in these plans. It is also expected that this report will be a foundation for enhanced coordination with GSAs as planning occurs in their regions. Click below for document appendices.  Appendix A: Selected GSP Information Summaries by Hydrologic Region Appendix B: Appendix B 1 - Sac Valley Hydrologic Region - GSP Hydrogeologic Conceptual Model Excerpts and Near AEM Profiles Appendix B 2 - San Joaquin Valley Hydrologic Region - GSP Hydrologic Conceptual Model Excerpts and Near AEM Profiles Appendix B 3 - Tulare Lake Hydrologic Region - GSP Hydrogeologic Conceptual Model Excerpts and Near AEM Profiles

CV-SALTS Prioritization & Optimization Study: Final Baseline Characterization Report

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | March 9th, 2024

The Central Valley Regional Water Quality Control Board (Central Valley Water Board) first adopted a three-phased Salt Control Program into the water quality regulations

The Central Valley Regional Water Quality Control Board (Central Valley Water Board) first adopted a three-phased Salt Control Program into the water quality regulations applicable to the Central Valley Region of California in 2018; these regulations were subsequently amended in 2020. Phase I of the Salt Control Program requires implementation of the Prioritization and Optimization (P&O) Study. The primary purposes of this Study are to characterize existing salinity conditions in surface water and groundwater in the Central Valley Region, establish appropriate salinity targets for the protection of beneficial uses, and facilitate the development of long-term salt management alternatives for implementation in Phases II and III of the Salt Control Program.

CVFPP Conservation Strategy Appendix A. Regulatory Setting

California Department of Water Resources (DWR) | July 14th, 2016

Section 7.0 of the Conservation Strategy describes regional permitting efforts that are being developed by the California Department of Water Resources (DWR) in v

Section 7.0 of the Conservation Strategy describes regional permitting efforts that are being developed by the California Department of Water Resources (DWR) in various stages of implementation. This appendix provides a more thorough description of the State and federal regulatory approvals that will be required for implementation of the Central Valley Flood Protection Plan (CVFPP), including the Conservation Strategy.

CVFPP Conservation Strategy Appendix B. Advance Mitigation

California Department of Water Resources (DWR) | July 14th, 2016

Section 7.0 of the Conservation Strategy presents methods for coordinating the acquisition of permits for implementation of the Central Valley Flood Protection Plan (CVFP

Section 7.0 of the Conservation Strategy presents methods for coordinating the acquisition of permits for implementation of the Central Valley Flood Protection Plan (CVFPP). These approaches have been initiated and are expected to be used in the future to mitigate impacts on species and habitats that result from CVFPP actions. As explained in Section 7.0, one regional permitting tool used by the California Department of Water Resources (DWR) is the development of advance mitigation projects.  This appendix further describes the purpose and benefits of advance mitigation, DWR’s efforts to date, and the process for selecting the first set of advance mitigation projects that will support the CVFPP. Each advance mitigation project has been, or will be, carefully selected in collaboration with permitting agencies to mitigate the effects of activities that will be implemented by DWR and Local Maintaining Agencies in the Systemwide Planning Area (SPA). DWR and the resource agencies are continuing to develop the mechanisms for crediting and a process for tracking the credits. Future advance mitigation projects are likely to follow the same process described herein. 

CVFPP Conservation Strategy Appendix C. Description of Construction Activities for Structural Modifications

California Department of Water Resources (DWR) | July 14th, 2016

This appendix [to the CVFPP Conservation Strategy] provides a general description of construction activities, focused on levee construction. It is based on the Program En

This appendix [to the CVFPP Conservation Strategy] provides a general description of construction activities, focused on levee construction. It is based on the Program Environmental Impact Report (PEIR) for the 2012 Central Valley Flood Protection Plan (CVFPP) (California Department of Water Resources [DWR] 2012).