Sacramento River

Central Valley Project: Issues and Legislation

Congressional Research Service (CRS) | November 25th, 2019

Central Valley Project: Issues and Legislation

Congressional Research Service (CRS) | June 23rd, 2021

The Central Valley Project (CVP), a federal water project owned and operated by the U.S. Bureau of Reclamation (Reclamation), is one of the world’s largest water supply

The Central Valley Project (CVP), a federal water project owned and operated by the U.S. Bureau of Reclamation (Reclamation), is one of the world’s largest water supply projects. The CVP covers approximately 400 miles in California, from Redding to Bakersfield, and draws from two large river basins: the Sacramento and the San Joaquin. It is composed of 20 dams and reservoirs and numerous pieces of water storage and conveyance infrastructure. In an average year, the CVP delivers more than 7 million acre-feet of water to support irrigated agriculture, municipalities, and fish and wildlife needs, among other purposes. About 75% of CVP water is used for agricultural irrigation, including 7 of California’s top 10 agricultural counties. The CVP is operated jointly with the State Water Project (SWP), which provides much of its water to municipal users in Southern California. CVP water is delivered to users that have contracts with Reclamation, which is part of the Department of the Interior. These contractors receive varying levels of priority for water deliveries based on several factors, including hydrology, water rights, prior agreements with Reclamation, and regulatory requirements. The Sacramento and San Joaquin Rivers’ confluence with the San Francisco Bay (Bay-Delta or Delta) is a hub for CVP water deliveries; many CVP contractors south of the Delta receive water that is “exported” from north of the Delta. Development of the CVP resulted in significant changes to the area’s natural hydrology. However, construction of most CVP facilities predated major federal natural resources and environmental protection laws. Much of the current debate related to the CVP revolves around how to deal with changes to the hydrologic system that were not significantly mitigated for when the project was constructed. Dry conditions since the onset of these requirements—including a prolonged drought from 2012 to 2016 and dry conditions in 2020 and 2021—have once again led to curtailment of water supplies and increased the stakes of these debates. Various state and federal proposals are currently under consideration and have generated controversy for their potential to affect CVP operations and allocations. In late 2018, the State of California finalized revisions to its Bay-Delta Water Quality Control Plan that would require that more flows from the San Joaquin and Sacramento Rivers reach the Bay-Delta for water quality and fish and wildlife enhancement (i.e., reduced water supplies for other users). “Voluntary agreements” that might replace some or all of these requirements are currently being negotiated but have yet to be finalized. Concurrently, the Trump Administration attempted to increase CVP water supplies for users and made changes to long-term operations of the CVP in a 2019 biological opinion created under the Endangered Species Act (ESA; 87 Stat. 884. 16 U.S.C. §§1531-1544). California and environmental nongovernmental organizations have opposed these efforts and filed lawsuits to prevent implementation of the changes. The court issued a preliminary injunction on May 11, 2020, temporarily prohibiting Reclamation from implementing the operational changes through May 31, 2020; on June 24, 2020, the court declined to extend the preliminary injunction further. Efforts to add or supplement CVP storage and conveyance also are being considered and are under study by federal and state entities. Congress has engaged in CVP issues through oversight and legislation, most recently in the form of provisions enacted under the 2016 Water Infrastructure Improvements for the Nation (WIIN Act; P.L. 114-322). Among other things, this act authorized changes to CVP operations that attempt to provide increased water supplies for agricultural and municipal contractors under certain circumstances. In the same legislation, Congress also authorized funding for new water storage projects that are expected to benefit CVP operations. In the 117th Congress, legislators may consider bills and conduct oversight on efforts to increase CVP water exports compared to current baselines. Some in Congress have also weighed in on disagreements between state and federal project operators and the status of coordinated operations of the CVP and SWP. Congress is also considering whether to approve funding for new water storage projects and may consider legislation to extend or amend CVP authorities. R45342 June 3, 2021 Charles V. Stern Specialist in Natural Resources Policy Pervaze A. Sheikh Specialist in Natural Resources

Central Valley Project: Issues and Legislation

Congressional Research Service (CRS) | March 8th, 2022

The Central Valley Project (CVP), a federal water project owned and operated by the U.S. Bureau of Reclamation (Reclamation), is one of the world’s largest water supply

The Central Valley Project (CVP), a federal water project owned and operated by the U.S. Bureau of Reclamation (Reclamation), is one of the world’s largest water supply projects. The CVP covers approximately 400 miles in California, from Redding to Bakersfield, and draws from two large river basins: the Sacramento and the San Joaquin. It is composed of 20 dams and reservoirs and numerous pieces of water storage and conveyance infrastructure. In an average year, the CVP delivers more than 7 million acre-feet of water to support irrigated agriculture, municipalities, and fish and wildlife needs, among other purposes. About 75% of CVP water is used for agricultural irrigation, including 7 of California’s top 10 agricultural counties. The CVP is operated jointly with the State Water Project (SWP), which provides much of its water to municipal users in Southern California.

Central Valley Region Salt and Nitrate Management Plan

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | January 19th, 2017

Elevated salinity and nitrates in surface water and groundwater are increasing problems affecting much of California, other western states, and arid regions throughout th

Elevated salinity and nitrates in surface water and groundwater are increasing problems affecting much of California, other western states, and arid regions throughout the world. In California, as surface and groundwater supplies become scarcer, and as wastewater streams become more concentrated, salinity and nitrate impairments are occurring with greater frequency and magnitude. In 2006, the Central Valley Water Board, the State Water Board, and stakeholders began a joint effort to address salinity and nitrate problems in California’s Central Valley and adopt long-term solutions that will lead to enhanced water quality and economic sustainability. Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) is a collaborative basin planning effort aimed at developing and implementing a comprehensive salinity and nitrate management program. The goal of CV-SALTS is to maintain a healthy environment and a good quality of life for all Californians by protecting our most essential and vulnerable resource: WATER. In July 2008, the Central Valley Salinity Coalition (CVSC) was formed.  CVSC represents stakeholder groups working with the Board in the CV-SALTS effort.  Its purpose is to organize, facilitate and fund efforts needed to fulfill the goals of CV-SALTS.  CVSC coordinates the meetings of the CV-SALTS committees, maintains an independent web site, and manages the projects originating from this effort.  Information and materials regarding the stakeholder committees and other activity, including the meeting schedule, are posted on their website: www.cvsalinity.org. The Final SNMP for Central Valley Water Board Consideration was completed in December 2016. The Central Valley Water Board staff plans to release this version of the SNMP and all of its supporting attachments in January 2017 for a comment period so that the public has the opportunity to review the SNMP documentation before a general information workshop is held with the Central Valley Water Board, currently planned for March 2017.

Challenges Facing the Sacramento-San Joaquin Delta: Complex, Chaotic, or Simply Cantankerous?

Delta Stewardship Council (Delta Council) | April 9th, 2015

In 2014, the California Natural Resources Agency and the U.S. Department of the Interior asked the authors of this paper, as four former leaders of The Delta Science Prog

In 2014, the California Natural Resources Agency and the U.S. Department of the Interior asked the authors of this paper, as four former leaders of The Delta Science Program, to summarize the challenges faced by water supply and ecological resource managers in this critically important region of Northern California. They concluded that the challenges are so complex as to meet the definition of a “wicked” problem. Such problems can’t be ignored, defy straightforward characterization, and have no simple solutions. Yet they must be actively managed to maximize beneficial and minimize adverse outcomes. In this context, the following paper calls for Delta management to become more nimble and better coordinated.

Changes in abundance and distribution of native and alien fishes of Suisun Marsh

American Fisheries Society (AFS) | July 29th, 1994

Overall fish abundance, abundance of introduced, native, and seasonal fish groups, and species diversity declined over a 14‐year period in Suisun Marsh, a portion of th

Overall fish abundance, abundance of introduced, native, and seasonal fish groups, and species diversity declined over a 14‐year period in Suisun Marsh, a portion of the San Francisco Bay estuary, and were associated with decreases in freshwater outflow and increases in salinity. Fish groups showed different patterns of abundance; large fluctuations in introduced and seasonal fish groups contrasted with a steady decline in native fish. Native species were found more often in small, dead‐end sloughs, seasonal species were found in larger sloughs, and introduced species were found in both habitats. Fish assemblage structure was less predictable than in an earlier (and shorter) study of the same community. Mixed groups of native and introduced species with similar freshwater and seasonal needs reflected effects of drought and increasing water diversions from the estuary. Chameleon goby Tridentiger trigonocephalus and yellowfin goby Acanthogobius flavimanus, two introduced species, fluctuated greatly in abundance in recent years, whereas other species declined steadily. Changes in fish abundance in the marsh reflect estuary‐wide changes and suggest that environmental disturbances coupled with introduced species are altering fish communities and hastening native fish declines.

Changing Channels: Regional Information for Developing Multi-benefit Flood Control Channels at the Bay Interface

San Francisco Estuary Institute (SFEI) | May 26th, 2017

Over the past 200 years, many of the channels that drain to San Francisco Bay have been modified for land reclamation and flood management. The local agencies that overse

Over the past 200 years, many of the channels that drain to San Francisco Bay have been modified for land reclamation and flood management. The local agencies that oversee these channels are seeking new management approaches that provide multiple benefits and promote landscape resilience. This includes channel redesign to improve natural sediment transport to downstream bayland habitats and beneficial re-use of dredged sediment for building and sustaining baylands as sea level continues to rise under a changing climate. Flood Control 2.0 is a regional project that was created to help develop innovative approaches for integrating habitat improvement and resilience into flood risk management at the Bay interface. Through a series of technical, economic, and regulatory analyses, the project addresses some of the major elements associated with multi-benefit channel design and management at the Bay interface and provides critical information that can be used by the management and restoration communities to develop long-term solutions that benefit people and wildlife. This Flood Control 2.0 report provides a regional analysis of morphologic change and sediment dynamics in flood control channels at the Bay interface, and multi-benefit management concepts aimed at bringing habitat restoration into flood risk management. The findings presented here are built on a synthesis of historical and contemporary data that included input from Flood Control 2.0 project scientists, project partners, and science advisors. The results and recommendations, summarized below, will help operationalize many of the recommendations put forth in the Baylands Ecosystem Habitat Goals Science Update (Goals Project 2015) and support better alignment of management and restoration communities on multi-benefit bayland management approaches.

Changing Channels: Regional Information for Developing Multi-benefit Flood Control Channels at the Bay Interface

San Francisco Estuary Institute (SFEI) | April 3rd, 2017

Over the past 200 years, many of the channels that drain to San Francisco Bay have been modified for land reclamation and flood management. The local agencies that overse

Over the past 200 years, many of the channels that drain to San Francisco Bay have been modified for land reclamation and flood management. The local agencies that oversee these channels are seeking new management approaches that provide multiple benefits and promote landscape resilience. This includes channel redesign to improve natural sediment transport to downstream bayland habitats and beneficial re-use of dredged sediment for building and sustaining baylands as sea level continues to rise under a changing climate. Flood Control 2.0 is a regional project that was created to help develop innovative approaches for integrating habitat improvement and resilience into flood risk management at the Bay interface. Through a series of technical, economic, and regulatory analyses, the project addresses some of the major elements associated with multi-benefit channel design and management at the Bay interface and provides critical information that can be used by the management and restoration communities to develop long-term solutions that benefit people and wildlife. This Flood Control 2.0 report provides a regional analysis of morphologic change and sediment dynamics in flood control channels at the Bay interface, and multi-benefit management concepts aimed at bringing habitat restoration into flood risk management. The findings presented here are built on a synthesis of historical and contemporary data that included input from Flood Control 2.0 project scientists, project partners, and science advisors. The results and recommendations, summarized below, will help operationalize many of the recommendations put forth in the Baylands Ecosystem Habitat Goals Science Update (Goals Project 2015) and support better alignment of management and restoration communities on multi-benefit bayland management approaches.

Changing ecosystems: a brief ecological history of the Delta

University of California, Davis (UC Davis) | February 15th, 2010

The San Francisco Estuary is a young estuary, about 6-10,000 years old in its present location. It became established during periods of high climatic variability (reflect

The San Francisco Estuary is a young estuary, about 6-10,000 years old in its present location. It became established during periods of high climatic variability (reflected in extreme floods and long droughts) compared to the relatively stable past 150 years. The Delta was formed as a huge freshwater marsh through the interaction of river inflow and the slow rise of sea level with the growth and decay of tules and other plants. This interaction resulted in the deposition of large amounts of organic matter, creating layers of peat that kept pace with sea level rise. These peat layers formed the soils of most of the present Delta ‘islands’, which were actually complex patches of floodable marsh. The channels among the islands were historically shifting, winding distributaries of the entering rivers that moved inflowing water through the Delta, providing access to upstream areas for large runs of migratory fish. The movement and quality of water in these channels was strongly affected by tidal action.  These attributes also created a complex of diverse and shifting habitats that supported a wide variety of functions for an ecological system in which there was no clear separation between aquatic and terrestrial components.

Characterizing and quantifying nutrient sources, sinks and transformations in the Delta: synthesis, modeling, and recommendations for monitoring

San Francisco Estuary Institute (SFEI) | January 5th, 2016

The Sacramento-San Joaquin Delta (the Delta) receives high loads of the nutrients nitrogen (N) and phosphorous (P) from wastewater treatment effluent and agricultural run

The Sacramento-San Joaquin Delta (the Delta) receives high loads of the nutrients nitrogen (N) and phosphorous (P) from wastewater treatment effluent and agricultural runoff. Flows from the Sacramento River, San Joaquin River, and other tributaries transport these loads through a complex network of rivers, channels and flooded islands, before entering San Francisco Bay. Excessive loads of N and P can adversely impact ecosystem health by causing excessive algal blooms and low dissolved (Valiela et al, 1992; Kamer and Stein 2003). Excessive nutrients may also contribute to the occurrence of harmful algal blooms (Bates et al, 1989) and overgrowth of nuisance aquatic macrophytes (Valiela et al, 1992). Major nutrient management decisions are being considered in both the Delta and San Francisco Bay, and those decisions require the best-available science to understand the factors that regulate ambient conditions, and the effects of loads and ambient conditions on ecosystem health. A mechanistic and quantitative understanding of nutrient cycling and fate in the Delta is essential both for informed decisions related to current conditions and also because of major anticipated changes in both loads to the Delta (upgrades at wastewater treatment facilities) and habitat function due to restoration efforts and water management. We hypothesized that the Delta is an important biogeochemical reactor, and that transformations or losses strongly regulate ambient nutrient concentrations within the Delta and modulate nutrient loads to San Francisco Bay. Both N and P have complex cycles and require careful investigation. In this paper, we focus on nitrogen, including loads, cycling, and losses or transformations that influence its ultimate fate.