In this video from American Experience, learn about the building the Grand Coulee Dam in the 1930's and 1940's, then the largest concrete structure ever built in the United States. It was essentially a large ditch that diverted water out of the Columbia River and fed the river to drier land to irrigate it. The water also moved turbines to generate electricity. But it destroyed the fishing areas of Native Americans. Hailed for its power to transform a region, it now serves as a reminder of the price of progress.