Hoover Dam: Historic Feat of Human Engineering
Although first proposed in 1902, when construction began 29 years later, the Hoover Dam was built to prevent flooding to downstream farming communities when snowmelt from the Rocky Mountains surged down the Colorado River.
The dam would also provide a massive source for hydroelectric power, while providing a dependable supply of water for Los Angeles and other southern California communities. Built during the lean years of The Great Depression, in 1931, construction began on one of the largest manmade structures ever built, employing 21,000 men, which in the process of completion would take the lives of more than 100 workers.
How the Hoover Dam was Built
The winning bid to build the dam was undertaken by a consortium of contractors known as Six Companies, Inc., employing innovative cement-casting techniques that had never been tried on such a massive scale. The biggest challenge was one of sheer concrete volume.
Comprised of 6.6 million tons of concrete, it was an unparalleled engineering marvel of its time, which still takes the breath away from over seven million visitors each year. If they had poured all of the Hoover Dam’s concrete volume at one go, it would take 125 years to cool and cure, along with uneven setting and potentially catastrophic cracking.
As a result, construction superintendent, Frank Crow, nicknamed “Hurry Up Crow,” came up with an ingenious method of cooling the concrete faster. His solution was to pass extremely cold water from a nearby refrigeration plant through one-inch pipes embedded in each freshly-poured layer of concrete, which allowed construction of the dam to be completed two years ahead of schedule. When the resulting reservoir filled with water after construction was completed, Lake Meade at the time became the largest manmade lake in the world.
At full capacity, the volume of water in Lake Meade would bury the state of Connecticut ten feet deep, making the Hoover Dam one of the greatest engineerings marvels of the twentieth century.