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State Water Project

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WATER-ENERGY NEXUS:  STATE WATER PROJECT

The California State Water Project, owned and operated by DWR, delivers water to about 25 million Californians and 750,000 acres of irrigated farmland.  Getting water to these users requires a large amount of electricity.  In fact, the State Water Project is one of the largest single consumers of electricity in the state, using around 8,000 gigawatt-hours per year.  The State Water Project also generates a large amount of electricity each year at its reservoirs and in-conduit generating stations.  The State Water Project actually generates about half of all the energy it uses each year.  Even with all of the electricity the State Water Project uses, it only accounts for about 3% of statewide electricity use.

Energy generation and use along the State Water Project

The State Water Project starts in Oroville, California 70 miles north of Sacramento where water generates electricity as it is released from Oroville Dam.  The water then flows down the Feather River and then Sacramento River by gravity (where some of it is used along the way by farms and cities).  The water is then pumped out of the Sacramento/San Joaquin Delta where some of it is used in the San Francisco Bay Area.  The rest flows down the California Aqueduct to farms and cities in the San Joaquin Valley, Central Coast, and Southern California.  Along the way it must be lifted by several pumping stations.  Wherever the water flows down steep mountain sides, DWR has in-conduit generating stations to recapture as much energy as possible.  In the map below, click on the service area of the State Water Project Contractor to see the energy intensity of water being delivered to that point in the aqueduct. 

 

Note: the State Water Project delivers raw water, meaning before this water can be used for drinking it must be treated which may add between 50 and 650 kWh/AF.  It must also be delivered to a point of use which will require additional energy.  These energy intensity calculations do not include electricity generated at the Oroville Reservoir complex.

DWR operates the State Water Project’s facilities to provide maximum benefit to the California electricity grid. DWR generates more electricity when statewide energy demands peak on hot summer days—reducing the need for inefficient and expensive power plants.  DWR operates its energy consuming facilities  more during evenings and nights when energy demand is low—this helps stabilize demand allowing other power plants to operate more efficiently.

Most water districts provide water from multiple sources so actual water delivered to customers will be a blend of different water sources such as groundwater and local surface water that may be higher or lower in energy intensity than SWP water.  Additional information about water sources used by individual water providers can be found by contacting the water provider or in the water provider's Urban Water Management Plan (http://www.water.ca.gov/urbanwatermanagement/2010uwmps/).

State Water Project electricity usage and Greenhouse Gases

DWR is committed to reducing the greenhouse gas (GHG) emissions associated with State Water Project electricity usage and adopted a GHG Emissions Reduction Plan in 2012. The plan calls for DWR to reduce emissions:

•50% below 1990 levels by 2020 and

•80% below 1990 levels by 2050.

As of 2014, DWR has already reduced its emissions 42% below 1990 levels and 22% below 2010 levels. (2014 Annual Emissions Report)

Clean Energy For the State Water Project, published in 2016 further documents and reports on DWR’s progress toward improving its energy portfolio, achieving its GHG Emissions Reduction Goals, and explains why certain strategies, such as installing solar over the California Aqueduct have been investigated but have not been implemented.