Central Valley Project - Controversy

Controversy

Once, profuse runs of anadromous fish—salmon, steelhead, and others—migrated up the Sacramento and San Joaquin Rivers to spawn in great numbers. The construction of CVP dams on the two rivers and many of their major tributaries—namely Friant Dam and Shasta Dam—mostly ended the once-bountiful Central Valley salmon run. From north to south, the Sacramento upriver of Shasta Dam, the American upriver of Folsom Dam, the Stanislaus upriver of New Melones Dam, and the San Joaquin upriver of Mendota—have become inaccessible to migrating salmon. In three of these cases, it is because the dams are too high and their reservoirs too large for fish to bypass via fish ladders. The San Joaquin River, however, had a different fate. Almost 60 mi (97 km) of the river is dry because of diversions from Friant Dam and Millerton Lake. Even downstream of Mendota, where the Delta-Mendota Canal gives the river a new surge of water from the Sacramento-San Joaquin Delta, irrigation runoff water, contaminated with pesticides and fertilizer, has caused the river to become heavily polluted. To make matters worse, efforts by the California Department of Fish and Game to route the San Joaquin run into the Merced River in the 1950s failed because the salmon did not realize the Merced as their "home stream".

Not only on the San Joaquin River have CVP facilities wreaked environmental havoc. On the Sacramento River, Red Bluff Diversion Dam in Tehama County, while not as large or as impacting as Friant Dam, also poses a barrier to the migration of anadromous fish. The fish passage facilities of the dam continually experienced problems from the beginning of operation in 1966, and introduced species that prey on young smolt often gather at the base of the dam, ultimately reducing the population of juvenile salmon that makes it into the Pacific. Further upstream, Keswick and Shasta Dams form total barriers to fish migration. Even out of the Central Valley watershed, the CVP's diversion of water from the Trinity River from Lewiston Dam into Whiskeytown Lake has significantly hurt the Klamath River tributary's salmon run. Over three-quarters of the river's flow is diverted through the Clear Creek Tunnel and away from the Trinity River, causing the river below the dam to become warm, silty, shallow and slow-flowing, attributes that hurt young salmon. Furthermore, the Trinity Dam forms a blockade that prevents salmon from reaching about 109 miles (175 km) of upriver spawning grounds. In the early years of the 21st century, the Bureau of Reclamation finally began to steadily increase the water flow downstream from Lewiston Dam. While providing less water for the CVP altogether, the new flow regime allows operations to meet the line drawn by Reclamation itself in 1952 stating that at least 48% of the river's natural flow must be left untouched in order for Trinity River salmon to survive. The lack of flow in the Trinity up to then was also a violation of the authorization that Congress made over the operation of the dam. The "...legislation required that enough be left in the Trinity for in-basin needs, including preservation of the salmon fishery."

In the early years of the 21st century, the Bureau of Reclamation studied the feasibility of raising Shasta Dam. One of the proposed heights was 18.5 feet (5.6 m) greater than its current size, thus increasing the storage capacity of Shasta Lake by 636,000 acre feet (784,000 dam³). The agency also proposed a smaller raise of 6.5 ft (2.0 m) that would add 290,000 acre feet (360,000 dam³). Previously, a 200 ft (61 m) raise of the dam, increasing storage to 13,890,000 acre feet (17,130,000 dam³), was considered, but deemed uneconomical. When Shasta Dam was first built, it was actually planned to be two hundred feet higher than it is now, but Reclamation stopped construction at its present height because of a shortage of materials and workers during World War II. The raising of the dam would further regulate and store more Sacramento River water for dry periods, thus benefiting the entire operations of the CVP, and also generating additional power. However, the proposed height increase was fought over for many reasons. Raising the dam would cost several hundred million dollars and raise the price of irrigation water from Shasta Lake. It would drown most of the remaining land belonging to the Winnemem Wintu tribe—90 percent of whose land already lies beneath the surface of the lake—and flood several miles of the McCloud River, protected under National Wild and Scenic River status. Buildings, bridges, roads and other structures would have to be relocated. The added capacity of the reservoir would change flow fluctuations in the lower Sacramento River, and native fish populations, especially salmon, would suffer with the subsequent changes to the ecology of the river.

New Melones Dam has come under even greater controversy than Shasta Dam, mainly because of the project's conflicts with federal and state limits and its impact on the watershed of the Stanislaus River. The original Melones Dam, submerged underneath New Melones Lake (hence the name New Melones Dam) is the source of one of these problems. The disused Melones Dam blocks cold water at the bottom of the lake from reaching the river, especially in dry years when the surface of the lake is closer to the crest of the old dam. This results in the river below the dam attaining a much higher temperature than usual, hurting native fish and wildlife. To solve this problem, Reclamation shuts off operations of the dam's hydroelectric power plant when water levels are drastically low, but this results in power shortages. Originally, after the dam was constructed, the State of California put filling the reservoir on hold because of enormous public opposition to what was being inundated: the limestone canyon behind the dam, the deepest of its kind in the United States, contained hundreds of archaeological and historic sites and one of California's best and most popular whitewater rafting runs. Thus the reservoir extended only to Parrot's Ferry Bridge, 9 mi (14 km) below its maximum upriver limit, until the El Niño event of 1982-1983, which filled it to capacity within weeks and even forced Reclamation to open the emergency spillways, prompting the state and federal governments to repeal the limits they had imposed on the reservoir. Furthermore, the project allows a far smaller sustainable water yield than originally expected, and Reclamation calls the dam "a case study of all that can go wrong with a project".

In response to these environmental problems, Congress passed in 1992 the Central Valley Project Improvement Act (CVPIA), Title 34 of Public Law 102-575, to change water management practices in the CVP in order to lessen the ecological impact on the San Joaquin and Sacramento Rivers. Actions mandated included the release of more water to supply rivers and wetlands, funding for habitat restoration work (especially for anadromous fish spawning gravels), water temperature control, water conservation, fish passage, increasing the service area of the CVP's canals, and other items.