The date is July 7, 1931. The place is 35 miles outside of Las Vegas (not that there was much of a ‘Las Vegas’ to be ‘outside of’ back then), in the Black Canyon of the Colorado River, straddling Nevada and Arizona. Relying on a river, especially one as temperamental as the Colorado, for water is a tricky business: she’s either being stingy and withholding, or she’s flooding the surrounding area.
The solution? A big ol’ dam.
*Enter President Herbert Hoover.*
America was in the depths of the Great Depression, and President Hoover saw an opportunity to address multiple issues at once. Building a dam would create work for thousands at a time when nearly a quarter of the population was unemployed. It would help control flooding, and create a reservoir, so access to water was more predictable and less deadly. And it would create enough hydroelectric power to service millions in the region – can you imagine the Las Vegas strip without that electricity?
Nevada is famous for many things: gambling, drive thru weddings, quickie divorces (surprisingly not related to the aforementioned insta-nuptials), silver mining, atomic testing, Area 51 and related extraterrestrial conspiracy theories. Of all of these, only silver mining (Comstock lode, anyone?) and the robust divorce industry predate the Hoover Dam. The rest could rightfully be held to have been made possible by this incredible feat of engineering.
So, without further ado, a bunch of cool facts (and one myth) about the Hoover Dam:
- Competition for jobs was fierce. Throngs of people came West to queue up for hiring long before the project began, and before there was accommodation for them. Eventually Boulder City was created to house the workers, as well as rough and ready encampments closer to the site. At the height of construction, 5000 workers were on site each day.
- The death toll was high. Official numbers have worker deaths at around 100. Not to diminish the tragedy, but in some respects it’s surprising it was only 100, given the extreme heat, remoteness of the site, and taking “Working at Heights” to a whole new level (pardon the pun).
- Mythbusting time: despite aforementioned death toll, and contrary to popular belief, there are no bodies in the Hoover Dam. There are two reasons this urban legend is untrue – neither of which is “that’s horrifying and ghoulish”, but rather strictly pragmatic. One, concrete in large slabs takes a long time to harden (about 16 hours for the size of sections they were pouring) so there would have been more than enough time to get a worker out, living or dead. Two, if there were a body in the concrete, as it decomposed it would undermine the structural integrity of the dam.
- Dam(n) did people dislike President Herbert Hoover, as evidenced by the fight over naming rights. While this project was successful and an economic boon to the area and those employed, the Depression lasted throughout Hoover’s presidency, and became associated with, if not blamed on, him. There had long been back and forth about the name as locals preferred calling it the Boulder Dam, and when FDR succeeded Hoover into office, his administration officially changed the name from Hoover to Boulder (petty, perhaps, but satisfying). After FDR’s death, President Harry Truman signed the name Hoover Dam back into Congress.
- The Hoover Dam was the largest-scale concrete project that had ever been completed. The total volume of concrete used is approximately 4.4 million cubic yards (3.4 million cubic meters). If cubic yardage of concrete means absolutely nothing to you (looking at myself here), this is enough concrete to build a two-lane highway from San Francisco to New York City.
- It’s an arch-gravity dam; a type of dam that combines the characteristics of both an arch dam and a gravity dam. (Duh, right?). It is designed to resist the forces of water pressure through a combination of its own weight (that’s the gravity bit) and the arch action. Arch dams resist the horizontal thrust created by the water pressure. It converts the horizontal forces into vertical forces, which are then transferred downwards along the abutments. This arch action helps to counteract the tendency of the dam to overturn or slide downstream.
- The Hoover Dam is still curing. No, not the healing lepers sort of curing. While the dam was completed in 1936, the chemical process of hydration, which is responsible for the hardening and strengthening of concrete, continues over an extended period.
- Lake Mead, the Hoover Dam’s reservoir. is one of the largest man-made reservoirs in the United States. It has a total storage capacity of approximately 28.9 million acre-feet (35.7 billion cubic meters) of water when full, which is roughly equivalent to about two years’ worth of the Colorado River’s average flow.
- Cooling System: To prevent the dam from overheating, a cooling system was installed. The system circulates chilled water through a network of pipes embedded within the concrete. This helps regulate the temperature of the dam and prevents excessive expansion and contraction.
- It was a massively expensive undertaking ($49 million, or $760 in today’s dollars) – so much so that six companies had to form a consortium, which they very creatively called Six Companies. In case it ever comes up at bar trivia, the companies were: Morrison-Knudsen Company (Boise, Idaho), Utah Construction Company (Ogden, Utah), Pacific Bridge Company (Portland, Oregon), Henry J. Kaiser Company (Oakland, California), MacDonald & Kahn Ltd. (Los Angeles, California), J.F. Shea Company (Portland, Oregon). This was not the beginning of a beautiful friendship – they worked together well, but the consortium dissolved and the companies continued to work as independent organizations.
- The final numbers: The Hoover Dam stands at a height of 726 feet (221 meters) and stretches across the canyon for 1,244 feet (379 meters). The dam contains over 3.25 million cubic yards (2.5 million cubic meters) of concrete and weighs over 6.6 million tons. On average, it produces about 4.5 billion kilowatt-hours of electricity per year, supplying power to approximately 1.3 million people in Arizona, Nevada, and California.
The Hoover Dam remains an iconic symbol of engineering excellence and a major tourist attraction. It showcases the achievements of the men and women who worked on its construction and continues to provide significant benefits to the region to this day.