San Joaquin River

Oppose the Twin Tunnels Project: A C-­WIN Policy Brief

California Water Impact Network (C-WIN) | October 1st, 2012

It is the policy of the California Water Impact Network to: • Oppose and work to defeat the construction of the Twin Tunnels Project which would divert water from th

It is the policy of the California Water Impact Network to: • Oppose and work to defeat the construction of the Twin Tunnels Project which would divert water from the Sacramento River to the South Delta pumps before it gets to the Bay-­Delta. • Support and work to achieve the reduction in Delta exports to a maximum of 3 million acre-­feet per year.  Oppose any increased Delta exports to Central and Southern California. • Support and work to achieve the elimination of paper water from State Water Project and Central Valley Project contracts. • Support regional water self-­sufficiency through conservation, recycling, storm water capture and other “soft path” means. • Support upgrading Delta levees to withstand both sea level rise and the risk of a major earthquake. •  Support increased water supply reliability for State Water Project urban areas by reinstatement of the Urban Water Preference in State Water contracts and returning the Kern Water Bank to the public to store the Urban Preference south of the Delta as a drought supply.

Optimizing the dammed: Water supply losses and fish habitat gains from dam removal in California

Journal of Environmental Management (Elsevier) | April 1st, 2014

Dams provide water supply, flood protection, and hydropower generation benefits, but also harm native species by altering the natural flow regime and degrading aquatic an

Dams provide water supply, flood protection, and hydropower generation benefits, but also harm native species by altering the natural flow regime and degrading aquatic and riparian habitat. Restoring some rivers reaches to free-flowing conditions may restore substantial environmental benefits, but at some economic cost. This study uses a systems analysis approach to preliminarily evaluate removing rim dams in California's Central Valley to highlight promising habitat and unpromising economic use tradeoffs for water supply and hydropower. CALVIN, an economic-engineering optimization model, is used to evaluate water storage and scarcity from removing dams. A warm and dry climate model for a 30-year period centered at 2085, and a population growth scenario for year 2050 water demands represent future conditions. Tradeoffs between hydropower generation and water scarcity to urban, agricultural, and instream flow requirements were compared with additional river kilometers of habitat accessible to anadromous fish species following dam removal. Results show that existing infrastructure is most beneficial if operated as a system (ignoring many current institutional constraints). Removing all rim dams is not beneficial for California, but a subset of existing dams are potentially promising candidates for removal from an optimized water supply and free-flowing river perspective. Removing individual dams decreases statewide delivered water by 0–2282 million cubic meters and provides access to 0 to 3200 km of salmonid habitat upstream of dams. The method described here can help prioritize dam removal, although more detailed, project-specific studies also are needed. Similarly, improving environmental protection can come at substantially lower economic cost, when evaluated and operated as a system.

Order Approving Temporary Urgency Changes to Water Right License and Permit Terms Relating to Delta Water Quality Objectives

California State Water Resources Control Board (SWRCB) | February 21st, 2023

Origins of Extreme Climate States during the 1982–83 ENSO Winter

American Meteorological Society (AMS) | November 1st, 1997

Oroville Dam: A key unit of the State Water Project

California Department of Water Resources (DWR) | July 1st, 1973

Our Vision for the California Delta

Delta Vision Blue Ribbon Task Force (Delta Vision) | March 19th, 2008

Our Vision for the California Delta

Delta Vision Blue Ribbon Task Force (Delta Vision) | March 19th, 2008

Executive Order S-17-06, directed us to “develop a durable vision for sustainable management of the Delta” with the goal of “...managing the Delta over the long te

Executive Order S-17-06, directed us to “develop a durable vision for sustainable management of the Delta” with the goal of “...managing the Delta over the long term to restore and maintain identified functions and values that are determined to be important to the environmental quality of the Delta and the economic and social well being of the people of the state.” The executive order calls for our vision to be completed by January 1, 2008 and a strategic plan by November 2008.

Over‐pumping leads to California groundwater arsenic threat

Nature Portfolio (Springer Nature) | June 5th, 2018

Water resources are being challenged to meet domestic, agricultural, and industrial needs. To complement finite surface water supplies that are being stressed b

Water resources are being challenged to meet domestic, agricultural, and industrial needs. To complement finite surface water supplies that are being stressed by changes in precipitation and increased demand, groundwater is increasingly being used. Sustaining groundwater use requires considering both water quantity and quality. A unique challenge for groundwater use, as compared with surface water, is the presence of naturally occurring contaminants within aquifer sediments, which can enter the water supply. Here we find that recent groundwater pumping, observed through land subsidence, results in an increase in aquifer arsenic concentrations in the San Joaquin Valley of California. By comparison, historic groundwater pumping shows no link to current groundwater arsenic concentrations. Our results support the premise that arsenic can reside within pore water of clay strata within aquifers and is released due to overpumping. We provide a quantitative model for using subsidence as an indicator of arsenic concentrations correlated with groundwater pumping.

Pacific Coast Federation of Fishermen’s Associations et al v. Wilbur Ross et al

U.S. District Court, Northern District of California | December 12th, 2019

Paradise Regained: Solution for restoring Yosemite's Hetch Hetchy Valley

Environmental Defense Fund (EDF) | July 15th, 2004

In this report Environmental Defense provides a planning-level analysis for replacing the water and hydropower benefits that the Hetch Hetchy Reservoir and O’Shaughness

In this report Environmental Defense provides a planning-level analysis for replacing the water and hydropower benefits that the Hetch Hetchy Reservoir and O’Shaughnessy Dam provide.We show how practical, proven water storage, conveyance and treatment alternatives can provide San Francisco a healthy, reliable and secure supply of water that is adequate for current and future needs.  We also explain how hydropower lost as a result of restoring the valley can be replaced without contributing to air pollution or global warming. The alternatives analyzed do not comprise all possible options, but they do demonstrate that workable solutions for restoring Hetch Hetchy Valley exist. We began this study with the premise that all solutions must be technologically feasible and affordable and must assure a dependable supply of safe drinking water. In addition to addressing the water and power needs of San Francisco and other Bay Area communities that rely on the Tuolumne River, solutions must also protect all affected California communities. Most obviously, any restoration plan must protect the Turlock and Modesto Irrigation Districts, whose uses of the Tuolumne River predate and are intertwined with those of the San Francisco Public Utilities Commission (SFPUC) and its customers. Of course, a restoration plan must also consider the Groveland area, both as a user of the Tuolumne River water and as a gateway community to the Hetch Hetchy region of Yosemite National Park. Our analysis focuses mainly on alternative ways to move and store San Francisco’s existing supply of Tuolumne River water. Environmental Defense developed the TREWSSIM (Tuolumne River Equivalent Water Supply Simulation) model to evaluate the SFPUC’s system performance under a range of water supply alternatives, with and without Hetch Hetchy Reservoir.TREWSSIM incorporates features of both the SFPUC’s planning model HHSM-LSM and the state-federal CALSIM model. The TREWSSIM analysis addresses not only water supply issues, but also water treatment and hydropower. Three expert consultants assisted in our analysis: Schlumberger Water Services provided engineering analyses and modeling assistance; Eisenberg, Olivieri and Associates analyzed water quality issues; and Somach, Simmons  & Dunn assessed the legal landscape. Academic experts provided peer review. The San Francisco Public Utilities Commission, the Bay Area Water Supply and Conservation Agency, and the Turlock and Modesto Irrigation Districts also provided information to help ensure an accurate report.