The wonders of Shasta Dam. While approaching the dam which created Shasta Lake, I was ready to admire yet another marvel of American engineering. It turned out to be more than that: the history of the dam building, the shape and size of the lake, the view of Mount Shasta, the water temperature control to benefit the salmon of the Sacramento River.
Shasta Dam is a curved gravity concrete dam on the Sacramento River about 9 miles northwest of Redding, California, built between 1938 and 1945; it was a continuous pour concrete project, ranked as one of the great civil engineering feats of the world; it is reputedly the world’s highest center-overflow spillway. The dam is 602 ft (183.5 m) high and 3,460 ft (1,054.6 m) long, with a base width (thickness) of 883 ft (269.1 m). The reservoir created behind Shasta Dam, the largest reservoir in California, is known as Shasta Lake which provides flood control, power generation, water supply and recreation along its 375 miles (603.5 km) of shoreline (!!); the water stored in the reservoir represents about 41% of the available water in the entire California’s Central Valley and is used to irrigate over 3 million acres of farmland plus municipal and industrial needs.
 |
Construction of Shasta Dam began in 1938, concrete placement in 1940, and the building was accelerated during World War II. At the time when many gold and silver mines in Colorado were stripped of steel and iron machinery and tools, in effect closed, to reuse the material in warship building, over 28 thousand tons of steel was built into Shasta Dam. Power generation became a critical need for the war effort and Shasta Power Plant was put in service in 1944 and the dam was completed in 1945, full 22 months ahead of schedule. Until construction of Shasta Dam, Chinook salmon migrated to the upper reaches of the Sacramento Rivers to spawn. Being stopped at the dam, they found river water below the dam to worm for spawning. To meet water temperature objectives for salmon recovery efforts in the Sacramento River below Shasta Dam, a temperature control device was built in 1997; it selectively withdraws water from a range of reservoir depths, including the deeper, colder water, sending it through the power plant generators while at the same time it provides colder water for optimal spawning. The temperature control device cost approximately $80 million to design and build. Also, a special type of gravel was introduced in the river below the dam to mimic the upstream environment that the salmon could no longer reach. I’m deeply impressed by the environmental approach like this one. Maybe the people designing the temperature control unit were bewitched by the magnificent view of Mount Shasta over the lake, a dormant volcano with five living glaciers which towers to 14,162 ft (4317 m). There is a quote from notable naturalist John Muir (1874): "When I first caught sight of Mount Shasta over the braided folds of the Sacramento River, my blood turned to wine, and I have not been weary since." |
WEBSITE EDITOR:
Krešimir J. Adamić
