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 Mexico Territory, and Nevada state. They remained the primary means of transportation of freight until the advent of the more economical railroads began cutting away at their business from 1878 when the first line entered Arizona Territory. Steamboats were tried on the upper Colorado River: in Glen Canyon; on the Green River in Utah and Wyoming; and on the Grand River, (renamed as the upper part of the Colorado River after 1921), above its confluence with the Green River in Utah and in Colorado. These attempts in the late 19th Century and early 20th Century met with little success. The