Major Projects Completed
Bureau of Reclamation Commissioner Michael Connor addresses the audience at the dedication of the Delta-Mendota Aqueduct Intertie Project. The ceremony was held inside the pumping plant structure.
Delta-Mendota Canal/California Aqueduct Intertie Project
The Mid-Pacific Region completed the Delta-Mendota Canal/California Aqueduct Intertie Project in 2012, linking the two canals to improve operational flexibility and provide more efficient delivery of water to the San Joaquin Valley.
The Intertie in Alameda County, west of Tracy, will potentially increase average annual deliveries of the Central Valley Project by as much as 35,000 acre-feet by addressing conveyance conditions in the DMC that restrict use of the nearby C. W. “Bill” Jones Pumping Plant to less than its design capacity.
The DMC is the primary federal delivery facility conveying water to CVP contractors in the San Joaquin Valley. The State Water Project’s California Aqueduct operates in much the same way. The Intertie allows more conveyance to storage south of the Sacramento-San Joaquin Delta, provides redundancy in the distribution system in case of emergency, and makes maintenance and repair work less disruptive to water deliveries.
The project was dedicated in a May 2 ceremony attended by Reclamation Commissioner Michael Connor, who commended the partnership that made the project possible.
“Our goal is to keep moving these interim solutions forward, improving the situation from a water supply perspective and an environmental perspective,” said Connor.
Reclamation’s partners in the project were the California Department of Water Resources, which operates the State Water Project, and the San Luis and Delta-Mendota Water Authority. Operation and maintenance responsibility for the Intertie was transferred to the San Luis and Delta-Mendota Water Authority in July 2012.
The Department of the Interior committed $15.8 million from the American Recovery and Reinvestment Act to construct the Intertie. CALFED, a multi-agency program, provided $8.8 million. The remaining funding came from contributed funds and Reclamation’s budget. The total project cost was $29 million.
The two-way Intertie was constructed, beginning in 2010, at a point where the federal and state canals are just 500 feet apart, with the state canal 50 feet higher in elevation than the federal canal. With the canals now linked via two 108-inch diameter pipelines, Intertie operators can allow up to 900 cfs of water to flow from the state canal, downhill to the federal canal, via gravity flow. In a reversal of operations, If desired, Intertie operators can pump up to 468 cubic feet per second of water uphill from the federal canal to the state canal.
Construction involved removing a section of the DMC’s concrete liner, installing a cofferdam, and constructing an underground sump structure to collect and channel water from the canal. Above ground, workers erected a pump house and installed four sets of 1,000-horsepower motors and pumps, each with a capacity of 117 cfs. Crews also constructed a 4.5-mile overhead 69-kilovolt power transmission line from a Tracy substation to the site.
On the California Aqueduct side of the project, workers installed a cofferdam, then removed a section of concrete liner and excavated about 25 feet for a turnout structure. Crews completed the structure’s two reinforced concrete bays and laid the twin pipes to connect the canals.
The photo above and the diagram below show the Intertie and how the facility functions. On the left side of both the photo and diagram is the California Aqueduct and on the right side is the federal Delta-Mendota Canal. The building next to the DMC is a pumping plant. Water can flow downhill through underground pipes (shown in the diagram) from the higher California Aqueduct to the DMC. The pumping plant also can transfer water from the DMC, uphill, to the California Aqueduct.
Red Bluff Fish Passage Improvements/Pumping Plant
The Mid-Pacific Region worked through 2012 on construction of the Red Bluff Fish Passage Improvement Project near Red Bluff in Northern California, completing a new pumping plant and allowing the Red Bluff Diversion Dam gates to be permanently opened. The completion of the project represents the culmination of decades of efforts by various entities to find a balanced solution that improves fish passage and the reliability of irrigation water to highly productive farmland.
The improvement was required by the Central Valley Project Improvement Act of 1992 and reaffirmed by the National Marine Fisheries Service’s 2009 Biological Opinion for operation of the Central Valley Project, which mandated an alternative to Red Bluff Diversion Dam and raising of the gates year-round by 2012.
The existing Red Bluff Diversion Dam, when its gates were down, conveyed water from the Sacramento River into the Tehama-Colusa and Corning irrigation canals. But this created a barrier to migrating fish, some of which are listed under the Endangered Species Act.
The Red Bluff Diversion Dam, completed in 1964, contains a series of 11 gates that, when lowered, provided for gravity diversion of irrigation water from the Sacramento River into the Tehama-Colusa and Corning canals. The Red Bluff Diversion Dam had been an impediment to upstream and downstream fish migration, and a significant portion of the Sacramento River spawning habitat for endangered salmon and steelhead upstream of the dam. Adult fish moving upstream had difficulty finding and using the ladders for passage over the dam, and juveniles migrating downstream through the dam become disoriented by the turbulence, resulting in significant mortality from predator fish. The main species of concern were the winter- and spring-run Chinook salmon, Central Valley steelhead and green sturgeon.
Left: View of the screen and cleaner structure show the immense size of the project.
Right: Boat heads toward the open gates of the Red Bluff Diversion Dam.
The fish passage improvement project involved construction of a pumping plant, screened to protect fish, which conveys water from the Sacramento River to the irrigation canals. The pumping plant has replaced the diversion dam. The dam’s gates have been permanently placed in the open position for free migration of fish.
The new pumping plant ensures continued water deliveries to 150,000 acres of farmland throughout a four-county area, served by 17 water districts.
The $185 million in funding for the project includes $115.7 million from the 2009 American Recovery and Reinvestment Act, the largest single outlay of ARRA funding in the nation by the Department of the Interior.
During 2012, construction was completed on key components such as the pumping plant intake; the pumping plant itself, which included nine pumps that together have a pumping capacity of 2,000 cubic feet per second; an 1,118-foot-long fish screen structure; a canal siphon; a discharge conduit; and a 660-foot-long bridge that allows maintenance workers access to the project.
Workers are restoring the areas that were affected by construction. Earth that was moved is being returned to its natural shape and vegetation is being planted to return the region to its former condition.
Aerial view shows the scope of the Red Fish Passage Improvement Project.
February 22, 2013