The California Department of Water Resources announced an agreement Tuesday with the Contra Costa Water District related to potential water quality impacts to its water supply in the event California WaterFix is built.

Under the agreement, when California WaterFix becomes operational, the Department of Water Resources (DWR) would deliver a portion of the district’s water supply from a new source on the Sacramento River. In return, the Contra Costa Water District (CCWD) agrees to withdraw a pending protest over California WaterFix and not sue DWR over the project.

Read agreement [here]

Read summary [here]

Although California WaterFix would be operated to meet all water quality standards established by the State Water Resources Control Board, the agreement compensates CCWD for a potential increase in salinity at its Delta water supply intakes that does not exceed state standards.

“When and where possible,” said DWR Director Mark W. Cowin, “we have modified our proposed project to avoid or minimize potential negative effects on local communities, others who depend upon the Delta for water supplies, and fish and wildlife.”

“We’re pleased to announce this agreement to resolve concerns of the Contra Costa Water District and avoid unnecessary litigation. We’ll continue to listen to concerns, adjust the proposed project where possible, and commit to agreements to address concerns.”

CCWD General Manager Jerry Brown said, “We appreciate that the state has taken the time to sit down with CCWD to better understand our unique issues and has worked with us to resolve our water quality and supply concerns. We are confident that this is an iron-clad insurance policy to protect our customers. We wouldn’t have reached agreement otherwise.”

California WaterFix is a major project proposed by DWR and the U.S. Bureau of Reclamation now in the environmental review stage. It involves construction of three new intakes along the Sacramento River in the north Delta near Hood. The purpose of California WaterFix is to reduce the reliance of California’s two biggest water projects on two existing pumping plants in the south Delta that were built 49 and 65 years ago.

These pumping plants pull south and central Delta channels in unnatural directions potentially harmful to fish. As a result, the water projects that supply two-thirds of California’s population and a third of its farmland are often restricted from operating, even when flows into the Delta run high. With new Sacramento River intakes connected by 40-mile-long tunnels to the existing pumping plants, California WaterFix would protect fish against reverse flows caused by pumping and give operators of the State Water Project (SWP) and Central Valley Project (CVP) more opportunities to capture and store water at times of peak flow.

Modeling shows that the operation of new intakes on the Sacramento River, as proposed by California WaterFix, could at times change water quality in the south Delta near four intakes that CCWD uses to help supply its 500,000 customers. Those intakes are in the west Delta, at Mallard Slough near Pittsburg, and in the south Delta, at Rock Slough near Oakley and Old River and Victoria Canal near Victoria Island. All of CCWD’s intakes are subject to variations in water quality caused by salinity intrusion, Delta hydrodynamics, and discharges into the Delta and its tributary streams.

Under the agreement announced today, DWR would provide from the Sacramento River some of the water allowed for under the CCWD’s existing water rights and contracts, including with the U.S. Bureau of Reclamation.

The agreement describes several options for providing CCWD water via the Sacramento River:

* Use the Sacramento River intake operated by the East Bay Municipal Utility District near Freeport, after CCWD reaches agreement with EBMUD;

* Build a connection between the proposed California WaterFix tunnels and a CCWD pipeline where the conveyance systems would cross in the south Delta; or

* Build a short pipeline from Clifton Court Forebay in the south Delta under Victoria Island to connect with a CCWD pipeline.

The costs of moving the water through the EBMUD facility or building an intertie would be borne by the public water districts paying the costs of California WaterFix. These districts in the Santa Clara Valley, East Bay, San Joaquin Valley, and Southern California take delivery of water from the SWP and CVP.

Under the agreement, DWR would provide 30,000 acre-feet of water from the Sacramento River to CCWD the first year that California WaterFix is operational. In each subsequent year, the volume of water to be delivered under the agreement would be determined by a formula tied to the ratio of water diverted from the Sacramento River through the three new intakes of California WaterFix. The annual quantity of water to be conveyed under the agreement is expected to range between 2,000 acre-feet and 50,000 acre-feet. For the sake of comparison, CCWD has a federal contract for 195,000 acre-feet per year.

The purpose of the agreement is to address CCWD concerns that construction of California WaterFix could damage district facilities on and near Victoria Island and that operation of the project could cause salinity, algae and other contaminants to increase at CCWD’s intakes.

Modeling of the potential water quality impacts of California WaterFix finds that the construction, operation and maintenance of the proposed conveyance facilities would not result in any significant impacts on Delta water quality for any beneficial uses.

Mitigation for California WaterFix includes some tidal restoration that could result in minimal increases in methylmercury levels at locations nearest to the restoration areas.

The agreement guarantees CCWD that a certain portion of its supply will come from an upstream intake where water is generally less salty than the district’s supply. It also avoids litigation over potential water quality effects based on modeling results and ends a protest filed by the CCWD with the State Water Board. The State Water Board soon will begin hearings on an application by DWR and Reclamation to add three new California WaterFix points of diversion to the water rights of the SWP and CVP.

In a February ruling on how it would conducts its hearings, the State Water Board encouraged those concerned about the potential effects of California WaterFix to strike settlements outside of the Water Board hearing process to resolve potential issues.

“We’d like to take the same practical, solution-oriented approach with other parties as we’ve taken with CCWD,” said Director Cowin. “We look forward to more such agreements as we work to modernize our water projects in the Delta.”