Who doesn’t like a little history? Especially on a massive concrete structure like the Hoover Dam. We decided to look into the history of the Hoover Dam and how much effort it took to construct. The Hoover Dam was an engineering and architectural feat, especially in 1936. It was constructed in a total of five years, two years less than originally predicted. It cost $48.9 million, which would be the equivalent of $838.1 million today! The dam is 726 feet tall and 1,244 feet long. It is 660 feet thick at the base, which is the length of two football fields plus an additional 60 feet, and the top is 45 feet in thickness. There are 230 blocks of concrete at the base of of the dam, each block is five feet tall and anywhere from 25 to 60 square feet wide.
Prior to the start of construction of the dam, the first task was to divert the Colorado River. This wasn’t an easy task. A total of 16,000 feet of four diversion tunnels were cut into the Black Canyon which was then lined with concrete. It took an entire year to complete just this portion of the project. Once the water was diverted through the tunnels, scalers were suspended to work on the canyon walls to smooth them out enough for the dam’s walls to adhere to. Other crews worked on dredging the floor of the canyon down to its bedrock.
History was made on June 6, 1933, when concrete contractors poured the first bucket of concrete on the Hoover Dam. Railcars were used to transport the concrete that was mixed on-site from two batch plants, the concrete was then poured from an overhead bucket system. The bucket system was designed to pour one bucket of concrete every 78 seconds. It didn’t take long for contractors to realize the massive problem with this method. Pouring concrete using this method would then take 100 years for the concrete to cool and cure fully, which would then crack and the dam would be worthless.
Contractors had to come up with an innovative plan quick to speed up the curing process. They decided to place over 582 miles of one inch steel pipe throughout the concrete. A refrigeration plant was utilized by adding river water mixed with ice water to flow through the pipes to cool the concrete quickly. The plant was capable of producing 1000 lbs of ice a day. Once the concrete was set the pipes were no longer needed so they were filled in with concrete to further strengthen the dam. Using this technique the dam was built using separate interlocking blocks.
Two diversion tunnels were filled in August of 1933, then steel grates that weighed 1000 tons were placed over the two tunnels that remained in 1935. This allowed the water to channel towards the dam. Approximately 3.3 million cubic yards of concrete was used by contractors in the construction of the Hoover Dam. An additional million cubic yards of concrete was used for the power plant and supporting structures. This was enough concrete to build a double lane highway all the way from Miami, Florida to Seattle, Washington. The Hoover Dam was completed in 1935, this was primarily thanks to the concrete contractors that worked on it. Power began running in 1936, with the last turbine going online in 1961.
So with that being your super cool concrete history lesson for the day…. There are so many creative and custom options for finishing concrete, but first and foremost important is the concrete itself. At Custom Concrete Creations we have state of the art equipment and a properly trained team with years of experience. Custom Concrete Creations is a premier contractor serving the Omaha area as well at the Midwest. Give us a call or send us an email for your custom concrete finishing needs today!