Shasta Dam

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Shasta dam with Shasta Lake behind it and Mt. Shasta in the distance

Shasta Dam under construction. California, June 1942.

Shasta Dam is a curved gravity concrete dam (National ID No. CA10186) on the Sacramento River above Redding, California built between 1938 and 1945. Like another curved gravity dam (Hoover Dam), is was a continuous pour concrete project, and in its day, ranked as one of the great civil engineering feats of the world. The dam is 602 ft (183 m) high and 3,460 ft (1,055 m) long, with a base width or thickness of 543 ft (165.5 m). The reservoir created behind Shasta Dam is known as Shasta Lake and is a popular recreational boating area.

Shasta Dam is part of the Shasta and Trinity River Division of the Central Valley Project initially started with funds provided by the Emergency Relief Appropriation Act of 1935 (49 Stat. 115), authorized in December 1935; the Shasta and Trinity Division was authorized in August 1955. The original site, named Kennett after a nearby railroad station, was selected by the state of California as part of its 1933 Central Valley Project. However, unable to finance the construction of the project, the state turned to the Federal government for aid. The purpose of the Central Valley Project is that of water conservation and Shasta Dam was constructed primarily to protect the California Central Valley from water shortages and floods. The dam now provides flood control, irrigation and domestic water supply, electrical power generation, opportunities for recreation, and water quality enhancement.

There is a hydroelectric power plant at the base of the dam. The plant has a head of 100 m (330 ft) and its five Francis turbines have a combined capacity of 610 MW. It is the fourth largest hydroelectric plant in California, and the largest non-pumped-storage plant. Water to drive the turbines flows through 5 penstocks 15 feet in diameter, each large enough to permit passage to a school bus. To drive each turbine at full–generator load 85 tons of water are needed per second. Power is generated at 13,800 volts and is stepped up to 230 kV for transmission to Californian consumers. Some of these 230 kV wires connect to Path 66, which is part of a massive North-South power transmission project interlinking power grids on the West Coast.

In September 2004, legislation was passed to research the raising of the Shasta Dam. Supporters such as Senator Dianne Feinstein feel that the need for water is urgent. Opponents such as the Winnemem Wintu tribe feel that this is a dangerous plan for the environment and that other water conservation techniques can be better researched.

[edit] The Volcano

If one drives over the road built on the damface, one can also see Mount Shasta, a dormant stratovolcano. The state of California (with some Federal help) has seismically retrofitted the dam with a stainless-steel armature on the lake-side. Should Shasta Volcano come alive, and in the worst possible case, the state would have to flood and evacuate the Sacramento Valley in a planned and responsible manner.^{[Needs substantiation/reference]}

[edit] Trivia

Shasta Dam is higher than the Washington Monument and its spillway is three times the height of Niagara Falls.
It contains enough concrete to build a sidewalk 3 feet wide, 4 inches thick around the world at the Equator.
Shasta’s hydroelectric power plant, located just below the dam, is one of the biggest in California.