Grand Coulee Dam

Grand Coulee Dam is the largest concrete structure on the planet and the largest hydro- electric project in the U.S.  Its turbines are capable of producing 6809 megawatts. It generates more power than a million loco- motives. And that's just the beginning of impressive statistics about the size and capability of this dam. 

It took nine years, starting in 1933 during the Great Depression, to build the dam. Thousands worked around the clock, finishing the dam in 1942. Its 12 million cubic yards of concrete could build two standard six-foot wide sidewalks around the equator. The latest addition, completed in 1980, is the third power house (on the left side of the dam in the first picture). 

The second picture is a view of the third power house from the top of the dam. Its six turbines generate 80 percent of the power at the dam. Three turbines of the six in the new powerhouse are the world's largest turbines. The turbine shafts are 11 feet in diameter; the bolts used to bolt sections of these shafts together weight 900 pounds each. The new powerhouse functions primarily as a peak demand generator. 

The six feed pipes that bring water to the turbines in the new powerhouse are 40 feet in diameter. Two of those pipes at full capacity equal the flow of the Colorado River, according to our tour guide.

The dam actually has three important functions: irrigation, power production, and flood control. Electricity was not foreseen as its primary function when the dam was built, but today is one of the Dam's most important jobs. The pipes you see on the left hand side of the third picture are irrigation water pumps that life water from the Lake Roosevelt up 280 feet to allow water to flow into Banks Lake for irrigation and municipal water. Water from Grand Coulee Dam irrigates more than 500,000 acres today.

The final picture shows an osprey nest on top of a power pole near the dam. Ospreys are impressive birds of prey. In addition to very effective fish-catching skills in the dam, the ospreys have also virtually eliminated the pigeon problem around the dam. Managers at the dam audiotaped an osprey and play the tape periodically near the top of the maintenance crane on the dam. The crane is no longer "fowled" by pigeons.