Base of fresh water, groundwater salinity, and well distribution across California

National Academy of Sciences (NAS) | December 9th, 2020

The depth at which groundwaters transition from fresh to more saline—the “base of fresh water”—is frequently used to determine the stringency and types of measure

The depth at which groundwaters transition from fresh to more saline—the “base of fresh water”—is frequently used to determine the stringency and types of measures put in place to manage groundwater and protect it from contamination. Therefore, it is important to understand salinity distributions and compare defined bases of fresh water with salinity distributions and groundwater well depths. Here we analyze two distinct datasets: 1) a large set of total dissolved solids concentration (TDS) measurements (n = 216,754) and 2) groundwater well locations and depths (n = 399,454) across California. We find that 19 to 56% of the groundwater TDS measurements made at depths deeper than defined bases of fresh water pump fresh groundwater (TDS < 2,000 mg/L). Because fresh groundwater is found at depths deeper than the base of fresh water, current policies informed by base of fresh water assessments may not be managing and protecting large volumes of deep fresh groundwater. Furthermore, we find that nearly 4% of existing groundwater wells penetrate defined bases of fresh water, and nearly 16% of wells overlie it by no more than 100 m, evidencing widespread encroachment on the base of fresh water by groundwater users. Consequently, our analysis suggests that groundwater sustainability in California may be poorly safeguarded in some places and that the base-of-fresh-water concept needs to be reconsidered as a means to define and manage groundwater.

Basis of Design Report - Species Conservation Habitat

California Department of Water Resources (DWR) | April 14th, 2014

The Species Conservation Habitat (SCH) project provides shallow water habitat to support fish and wildlife dependent upon the Salton Sea that is being lost due to

The Species Conservation Habitat (SCH) project provides shallow water habitat to support fish and wildlife dependent upon the Salton Sea that is being lost due to salinity increases and the declining water surface elevation. The Project is located at the southern end of the Salton Sea (Sea) in Imperial County, California. Through the environmental review process, a Preferred Alternative was selected that encompasses 3,770 acres on both sides of the New River. The Project would include water supplies, berms to contain the water, and various other support facilities. The early start construction of the project is to develop habitat consistent with the EIS/EIR preferred alternative that is scaled down to fit the level of implementation funding currently available. The design described in this report is for early start project (Project) of the SCH and is limited to the 640 acres located within the bay on the east side of the New River. This report provides a summary of the primary design features and considerations associated with the habitat development. A more detailed discussion of the background, purpose, goals, design elements, Preferred Alternative, and Project impacts can be found in the 2011 draft EIS/EIR.  

Bay Delta Plan Phase 2 Workshop Summary Report

California State Water Resources Control Board (SWRCB) | January 1st, 2013

The California State Water Resources Control Board (Board) is tasked with updating the 2006 Water Quality Control Plan for the Bay-Delta Estuary (Bay-Delta Plan). The Boa

The California State Water Resources Control Board (Board) is tasked with updating the 2006 Water Quality Control Plan for the Bay-Delta Estuary (Bay-Delta Plan). The Board planning activities for this process have four phases. Phase 1 focused on San Joaquin River flow requirements and southern Delta water quality objectives. The current phase (Phase 2) focuses on fish and wildlife beneficial uses. Phase 3 will focus on modifications to water rights and Phase 4 will focus on the development and implementation of flow requirements for priority Delta tributaries. Phase 2 workshops were held to conduct discussions and generate information regarding the scientific and technical basis for considering potential changes to the Bay-Delta Plan. The workshops were informal; the Board did not take any official action and there was no sworn testimony. Information provided during the workshops will augment information developed through earlier reviews and will inform the Board members and staff on what, if any, changes should be made to the Bay-Delta Plan. Three workshops were held. Full workshop agendas are provided in Appendix A. 1. Ecosystem Changes and the Low Salinity Zone, September 5–6, 2012 – including the effects of the low salinity zone on various estuarine species, the interaction of salinity with non-flow related factors, and the identification of modeling or other tools that can be used to measure and reasonably protect estuarine habitat. 2. Bay-Delta Fishery Resources, October 1–2, 2012 – including flow, cold water pool, habitat, and water project operational constraints needed to reasonably protect Central Valley steelhead, Sacramento River winter-run, Central Valley late fall–run Chinook salmon, and pelagic species (including Delta smelt and longfin smelt); and the interaction of these issues with non-flow related factors. 3. Analytical Tools for Evaluating the Water Supply, Hydrodynamic, and Hydropower Effects of the Bay-Delta Plan, November 13–14, 2012 – including the CalSim II water supply model, DSM2 and RMA2 hydrodynamic models, Plexus hydropower model, and others as  applicable, together with results from applying these models to various scenarios.

Bay Delta Water Quality Control Plan (Bay Delta Plan)

California State Water Resources Control Board (SWRCB) | December 13th, 2006

"Bay Delta Plan" is short for the State Water Resources Control Board's (State Water Board) San Francisco Bay/Sacramento-San Joaquin Delta Estuary Water Quality Control P

"Bay Delta Plan" is short for the State Water Resources Control Board's (State Water Board) San Francisco Bay/Sacramento-San Joaquin Delta Estuary Water Quality Control Plan. The Bay-Delta Plan identifies the beneficial uses of the Bay-Delta, water quality objectives for the reasonable protection of those beneficial uses, and a program of implementation for achieving the objectives. The Bay-Delta Plan, when implemented, can determine the amount and timing of water entering and moving through the Delta. The State Water Board holds dual responsibilities of allocating surface water rights and protecting water quality. The State Water Board allocates water through an administrative system that is intended to maximize the beneficial uses of water while protecting the public trust, serving the public interest, and preventing the waste and unreasonable use or method of diversion of water. While most water quality control planning is done by the Regional Water Boards, the State Water Board has authority to adopt statewide water quality control plans. The State Water Board adopts the Bay-Delta Plan because of the Delta's importance as a major source of water supply for the state. The Bay-Delta Plan protects water quality in the region and includes water quality objectives to protect fish and wildlife beneficial uses through inflows to the Delta from the Sacramento and San Joaquin rivers and Delta outflows, in addition to objectives for salinity to protect agricultural beneficial uses. The State Water Resources Control Board (State Water Board) is in the process of a phased review and update of the 2006 Water Quality Control Plan for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary (Bay-Delta) (referred to as the 2006 Bay-Delta Plan). To learn more about the Bay-Delta Plan, click here. In 2009, the State Water Board began the process of reviewing and likely revising the 2006 Bay Delta Plan.  At the time of the archiving of this document, that update process still continues.  For the latest information, click here to visit the State Water Resources Control Board page for the Bay-Delta Plan Update.. RELATED DOCUMENT: Water Rights Decision 1641, the document that implements the 1995 Bay Delta Plan and is still in force.

Biological opinion on the coordinated operations of the Central Valley Project (CVP) and State Water Project (SWP)

U.S. Fish and Wildlife Service (FWS) | December 15th, 2008

On May 16, 2008, the U.S. Bureau of Reclamation and the California Department of Water Resources asked the Service to initiate consultation on the Long-Term Operational C

On May 16, 2008, the U.S. Bureau of Reclamation and the California Department of Water Resources asked the Service to initiate consultation on the Long-Term Operational Criteria and Plan (OCAP) for coordination of the Central Valley Project and State Water Project, specifically concerning the delta smelt and its critical habitat. (See OCAP Legal Archives.) On December 15, 2008, the Fish & Wildlife Service issued a biological opinion (BO) on the Long-Term Operational Criteria and Plan (OCAP) for coordination of the Central Valley Project and State Water Project. The Service determined that the continued operation of these two water projects, as described in the plan, was likely to jeopardize the continued existence of the delta smelt and adversely modify its critical habitat. The inclusion by the Service of reasonable and prudent alternatives, and their acceptance by the water agencies, avoided jeopardy and adverse modification.

Brackish Water Desalination Facility Draft Environmental Impact Report

City of Antioch | June 15th, 2018

The City proposes to construct, operate, and maintain the Antioch Brackish Water Desalination Project (proposed project). The City proposes to replace the existing San J

The City proposes to construct, operate, and maintain the Antioch Brackish Water Desalination Project (proposed project). The City proposes to replace the existing San Joaquin River intake pump station, construct a desalination facility with associated equipment and appurtenances; and construction of pipelines for the conveyance of source water and brine concentrate. The desalination plant would have the capacity to produce up to 6 million gallons per day (mgd) of desalinated product water to offset use of purchased water. Due to size, this file has been divided into two parts. Part 1, Part 2

Brackish Water Desalination Facility Project

Delta Stewardship Council (Delta Council) | April 1st, 2020

The City of Antioch (City) is proposing the Brackish Water Desalination Project (Project), which consists of the construction of a desalination facility at the City’s

The City of Antioch (City) is proposing the Brackish Water Desalination Project (Project), which consists of the construction of a desalination facility at the City’s water treatment plant (WTP) with the capacity to produce up to 6 million gallons per day (mgd) of finished water; demolition of the existing San Joaquin River intake pump station; construction of a new intake pump station; approximately 3,000 feet of pipeline from the existing raw water pipeline underneath Lone Tree Way to the City’s WTP to allow a direct connection to maximize use of existing infrastructure; and approximately 4 miles of pipeline from the desalination facility to the Delta Diablo wastewater treatment plant (WWTP) to discharge brine with the WWTP effluent through the existing Delta Diablo outfall to New York Slough. The Project facilities would be located in the cities of Antioch and Pittsburg, California (Figure 1), at the western edge of the San Joaquin- Sacramento Delta (Delta). The main objectives of the Project are to improve water supply reliability and water quality for its customers; develop a reliable and drought-resistance water source to reduce dependency on purchased water supplies; maximize and preserve the use of the City’s pre-1914 water rights; and provide cost effective operational flexibility for the City.

Bulletin No. 22, Volume I, Report on Salt Water Barrier below Confluence of Sacramento and San Joaquin Rivers, California

California Department of Water Resources (DWR) | August 27th, 1929

This report was split into two documents because of file size. Click here for Part 1 and  here for Part 2

This report was split into two documents because of file size. Click here for Part 1 and  here for Part 2

Bulletin No. 22, Volume II, Drawings Accompanying Report on Salt Water Barrier below Confluence of Sacramento and San Joaquin Rivers, California

California Department of Water Resources (DWR) | September 2nd, 1929

This document has been divided into four parts to reduce file size. Click here for Part 1 of 4, here for Part 2 of 4, here for Part 3 of 4 and here for Part 4 of 4

This document has been divided into four parts to reduce file size. Click here for Part 1 of 4, here for Part 2 of 4, here for Part 3 of 4 and here for Part 4 of 4

Bulletin No. 23-56, Surface Water Flow for 1956

California Department of Water Resources (DWR) | June 16th, 1959