The Hoover Dam which was originally known as the Boulder Dam, is located in the Black Canyon of the Colorado river and borders two states Arizona and Nevada.
Originally the Boulder Canyon was thought to be the best spot for the dam but the Black Canyon was selected instead. The Black canyon formed about 15 million years ago during the Miocene Basin and Range uplift and gets its name from the black volcanic rocks found throughout the area. It took 5 years to build. Construction began in 1931. Built during The Great Depression, over 42,000 men looking for work traveled to the area and over the course of its construction over 16,000 men and women worked on the project.
It is estimated that about 100 workers were killed during the building of the dam. Veterans of the Spanish-American War and WWI were supposed to be given preference and hired first. Some Native American workers were hired and while the Government said Black Americans would be hired for the project the number of Black workers never totaled more than 30 and the workers were segregated from white workers and had separate water buckets to drink from. One group of workers was excluded all together and that was Chinese workers as they were forbidden in the construction contract. Keep in mind, laws like the Chinese Exclusion Act are still the law of the land at this time in history.
Workers lived in Boulder City, which was developed specifically to house the workers. Boulder City was originally built in 1931 by the Bureau of Reclamation and Six Companies, Inc. as housing for workers who were building the Hoover Dam. The most important employees had their residences on top of the hill nearer the apex. Managers were housed further down the hill, and dwellings for manual laborers were located furthest away from the public buildings and parks. If you consider the make up the town, you can see that there is a hierarchy here. Living conditions in the town were poor. Work began on the project before the town could be finished. At first, workers lived in makeshift tents.
Before we can get into the building of the dam, we need to discuss why there was a need for one and why this location was chosen. Let’s start the dam story. Once upon a time the Colorado River flowed uninterrupted from the Rocky Mountains to the Gulf of California along a staggering 1,450 miles. The Colorado River was unpredictable--flooding in the spring as the snow from the Rocky Mountains melted, drying up in the summer and ran through some of California’s richest farmland. When the river overflowed, it devastated areas. When it dried up, everything died. In the early 1900s, the government began looking for ways to help encourage settlement in the west and to find ways to bring water to the people and allow for the cities that would hopefully spring up in this region. By the 1920s, the frequent damage caused by the river attracted enough attention that politicians sought out ways to control or tame the river. The solution was to build a dam.
The Boulder Canyon Project Act of 1928 authorized construction of a dam in Boulder, or Black, Canyon, construction of the All-American Canal to connect the Imperial and Coachella Valleys with the Colorado River, and divided the lower basin waters among the lower basin states. The Sec. of the Interior was given a budget of $165 million for construction. The act outlined the main purposes of the dam project. Flood control, improvement of navigation on the Colorado River, storage and delivery of water for reclamation and other beneficial uses, and for the generation of power. By generating power, they hoped that the project could recoup its large price tag. While neighboring states saw the need for such a project, not every state government was quick to approve the project. It required a significant amount of negotiating as many states feared California would get most of the water. The Colorado River Compact of 1922 divided the river into two basins: The Upper Basin (Colorado, New Mexico, Utah and Wyoming) and the Lower Basin (Arizona, California and Nevada). This agreement established the allotment for each basin and provided a framework for management of the river for years to come. Hoover’s involvement in the project is the reason the dam was renamed after him. But it wasn’t named after him right away.
US Bureau of Reclamation helped to build the dam.
When the Dam was completed, it was the largest concrete structure ever built. The project would not only provide much needed infrastructure, it would also provide much needed jobs.
The project was meticulously planned and designed. A 100-page document described the proposed plan and had 76 drawn images. As you can imagine, a number of companies were interested in the project, but few could afford the bid bond of 2 million dollars. A bid bond is issued as part of a bidding process to the project owner, to work as a guarantee that the winning bidder will undertake the contract under the terms at which they bid. There are usually penalties for not completing the job on time – which there was in the case of the Hoover Dam project should it not have been completed on time.
Six companies created a joint venture to place a bid for the project. It was known as Six Companies Inc. and they won the bid to build the dam. The dam has an arch gravity design. It was designed to curve upstream in a narrowing curve that would direct most of the water pressure against the canyon rock walls. The river first had to be diverted. Naturally, they had to work around the river and begin this stage of construction when the river was at its lowest. Four tunnels were drilled through the canyon walls using dynamite. The tunnels were then lined with concrete that was 3 feet thick. High scalers who were men attached to rope on the side of the canyon, drilled holes in the wall and put dynamite in. They would then have to remove the debris. The canyon surface had to be smoothed in order to prevent leaks. By 1932, they had diverted the river. Once they pumped the water out of the dam site, they began excavating the area to prepare it for the concrete.
One of the first major projects where workers were expected to wear hard hats. The workers dipped their hats in tar and once dry, they had hardened to protect them to a certain extent from falling debris. The helmets worn by soldiers during WWI was the inspiration. The helmets had saved the lives of so many men. The thought was that this innovation could be used in industrial projects. These first hats were known as hard boiled hats. Prior to the building of the Hoover Dam, protective headgear was optional. Now, it was mandatory.
Mixing plants were built to prep the concrete on site. Nine cable ways were used to lower the concrete into the molds. Workers worked continuously regardless of weather. 112 workers died during the construction of the dam.
The Concrete pours were also meticulously planned. Concrete gives off heat and contracts as it hardens. The pours had to be done in stages. Rectangular molds were created and fitted with steel pipes that carried water underneath to allow them to cool faster. Any cracks were then filled in before moving to the next section. The water pipes were also filled in and they would begin pouring the next section. Designers estimated that if they attempted to do the concrete in one continuous pour, it would take 125 years for the concrete to cool.
Hoover Dam´s authorized purposes are: first, river regulation, improvement of navigation, and flood control; second, delivery of stored water for irrigation and other domestic uses; and third, power generation.
Most people forget that The Hoover Dam is also a source of power for the region. Excavation for the powerhouse was carried out simultaneously with the dam’s foundation and abutments. The excavation of the U-shaped structure was completed in late 1933. This building wasn’t completed by the time of the dam’s dedication. By 1936, the water level of Lake Mead was high enough to begin generating power and by 1939, the dam’s power plant had become the largest hydroelectric facility in the world. Power generation has allowed the dam to be self-sustaining. The sale of power not only has paid for the 50-year construction loan but also pays for the upkeep of the dam.
Lake Mead, the nation’s largest reservoir, was formed by the Hoover Dam. It covers about 248 square miles and is capable of holding some 28.9 million acre-feet of water. The creation of Lake Mead (named for Elwood Mead, commissioner of the U.S. Bureau of Reclamation when the dam was being planned and built). Drought and increased water demand has kept the river well below capacity since 1983. Lake Mead today is at an all-time low. If water levels continue to drop the Hoover Dam could stop generating electricity.
As the water levels of Lake Mead continue to decline and the demand for water from Colorado river increases, the amount of power the Hoover Dam can make has decreased over the years.
The contractors finished their work two years ahead of schedule and millions of dollars under budget. On Sept. 30, 1935, the Boulder Dam was dedicated by President Franklin Roosevelt. Former President Herbert Hoover who was instrumental in the dam’s existence wasn’t invited to the ceremony, nor was he even mentioned. The names Boulder Dam and Hoover Dam were used interchangeably. I’ll give you one guess as to what FDR referred to it as…in April of 1947, President Harry Truman approved a congressional resolution that officially confirmed the dam would carry Hoover’s name. The Dam has been a target throughout history. After the attack on Pearl Harbor, private boats weren’t allowed in the canyon and the area wasn’t reopened until the war ended. There was even a plot by the German’s to attempt to bomb the dam. This was not a fact known to the average American during the time. In fact, it wasn’t publicly known until 2001 when old documents were uncovered. When the dam opened, US Route 93 ran across the top of the dam. As the population of the area grew, the road simply became too congested and in 2005 construction began on a dam bypass bridge and was completed in 2010. FDR, in his speech to dedicate the dam stated “This morning I came, I saw, and I conquered, as everyone would be who sees for the first time this great feat of mankind. Ten years ago the place where we gathered was an unpeople, forbidding desert. In the bottom of the gloomy canyon whose precipitous walls rose to height of more than a thousand feet, flowed a turbulent, dangerous river. The site of Boulder City was a cactus-covered waste. And the transformation wrought here in these years is a twentieth century marvel.”
