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2.4: State Water Project

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    The last major water infrastructure project undertaken for water supply in California was the State Water Project (SWP) and it still isn’t quite finished! The SWP major features were outlined in 1957 in the California Water Plan and it was funded by the Burns-Porter Act in 1960 in $1.75 Billion in general obligation bonds.

    Learning Objectives

    After reading this section, you should be able to:

    • Identify the major stakeholder groups and their needs
    • Analyze major threats to the Sacramento-San Joaquin Delta in terms of water supply
    • Project future impacts to the State Water Project

    The State Water Project is a massive infrastructure project that involves several major stakeholder groups throughout the state of California, all of which have been stakeholders in other water development projects that you’ve learned about:

    • Northern California communities that wanted flood control protection (as a result of devastating floods on the Feather River in 1955)
    • San Joaquin-Sacramento River Delta communities that wanted flood protection, but also access to high-quality water for farming
    • San Joaquin farmers who wanted access to water for expansion of agriculture, but also because of groundwater overdraft issues
    • Southern California residents who wanted water for future growth and for water supply reliability

    The State Water Project brought together these stakeholder groups with a combined mission of providing water supply to the San Joaquin Valley farmers as well as Southern California.

    The State Water Contract was among 32 public water agencies all over the state, including some agencies that formed specifically to contract for SWP water supplies. The terms of the contract were 75 years minimum or until the bonds were repaid. The State of California was obligated to make reasonable efforts to complete the project. The Contractors were obligated to pay even if the water supplies were reduced or the project was not complete. As you might guess, these aren’t great contract terms (paying for a project that is incomplete or reduced in some way).

    The State Water Project had several purposes: flood control (specifically at Lake Oroville), recreation (e.g., Pyramid Lake, Castaic Lake) and water supply (including primary reservoirs at Oroville and San Luis and terminal reservoirs at Pyramid and Castaic Lake, Lake Perris and Lake De Val). Facilities to convey water through the Delta and for additional storage were not completed.

    The Delta

    The Sacramento-San Joaquin Delta (sometimes referred to only as “the Bay-Delta" or “the Delta”) is one of the most interesting places in California to study in terms of stakeholders, science, and water supply.

    Image of the Sacramento-San Joaquin Bay-Delta by the U.S. Geological Survey is in the public domain
    Figure \(\PageIndex{1}\): Image of the Sacramento-San Joaquin Bay-Delta by the U.S. Geological Survey is in the public domain

    In terms of stakeholders, the Delta is home to historic towns and family farms. Many farms are under sea level with manmade levees their only protection. The Delta is also fully used for recreation—boating, fishing, sightseeing, bird watching (and duck hunting). There are also millions of stakeholders south of the Delta that rely on the water supply that passes through the Delta. So combine various stakeholders with a location that is literally described as the “heart” of the water supply and you can see how there might be inherent conflicts.

    Sacramento Delta by Matthew Trump is licensed under CC BY-SA 3.0
    Figure \(\PageIndex{2}\): Sacramento Delta by Matthew Trump is licensed under CC BY-SA 3.0

    The Delta has been altered by farmers over the past 150 years and it has also been altered by the operation of the State Water Project and Central Valley Project. It is currently threatened by three primary issues:

    Seismic—A large earthquake could break down the manmade levee system, allowing seawater into the Delta, and essentially making the water supply undrinkable for anyone south of the Delta

    Subsidence—Land within the Delta is made of peat soil, which is excellent for farming, but compacts and subsides over time, leading to levees sinking and needing to be repaired and strengthened

    Sea Level Rise—Sea level rise also threatens the Delta as there is often only a few feet between the top of the water and the top of the levee

    The most likely path forward is two twin tunnels under the Delta. This is known as the California Water Fix (formerly known as the Bay Delta Conservation Plan).

    Try It!

    1. Identify three purposes of the State Water Project.
    2. Write a letter advocating a plan to fix the Delta.

    Key Terms

    Burns-Porter Act—Funded the State Water Project in 1.75 billion in general obligation bonds in 1960

    This table summarizes the four major infrastructure projects covered.

    Los Angeles Aqueduct

    Central Valley Project

    Colorado River Aqueduct

    State Water Project


    Water supply reliability

    Flood control

    Water for irrigation


    Water supply

    Water supply

    Flood control

    Irrigation for farms


    Southern California residents

    Owens Valley ranchers, farmers, Paiute tribe

    San Joaquin Valley farmers

    Wyoming, Colorado, Utah, New Mexico, Nevada, Arizona, California

    Southern California residents

    San Joaquin Valley farmers

    Northern California communities with flood protection needs


    Central Valley
    Project Act of 1933

    Rivers and Harbors Act of 1935

    Central Valley Project Improvement Act in 1992

    All under The Law of The River:

    Colorado River compact of 1922

    Boulder Canyon Project Act of 1948

    Mexican Water Treaty of 1944

    Upper Colorado River Basin Act of 1948

    Minute 319

    California Water Plan

    Burns-Porter Act

    Major Features

    Owens Lake

    Mono Lake

    Lake Shasta

    San Luis Reservoir

    Lake Powell

    Lake Mead

    Lake Oroville

    San Luis Reservoir

    This page titled 2.4: State Water Project is shared under a CC BY license and was authored, remixed, and/or curated by Stephanie Anagnoson (ZTC Textbooks) .

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