Dam of its scale had ever been attempted; on completion, it was the largest masonry dam in the world. The Hoover Dam is a massive concrete arch-gravity dam, constructed in the Black Canyon of the Colorado River, on the border between the US states of Arizona and Nevada between 1931 and 1936 during the Great Depression. In 1928, Congress authorized the project to build a dam that would control floods, provide irrigation water and produce hydroelectric power. The winning bid to build the dam was submitted by a consortium called Six Companies, Inc. Such a large concrete structure had never been
Steamboats of the Colorado River the Colorado Steam Navigation Company between Yuma and Needles. By the end of 1905 all the steamboats, "Cochan", "St. Vallier" and "Searchlight", were withdrawn down river to Yuma. Their places were taken by smaller gasoline powered boats, until they were in turn replaced by trucks. The remaining steamboats worked on irrigation projects on the lower part of the river and on repairing the 1904-1907 breach in the Alamo Canal, that directed the Colorado River into the Salton Sink and created the Salton Sea before it was repaired. The last project, the construction of the Laguna Dam ended steam navigation on