Hoover Dam is one of the most famous hydro facilities in the world. Although it does not have a new world record, with its impressive size and history ot its construction, it is an example of how the non-viable project, from an engineering point of view, can become a reality.
The dam is a concrete arch-gravity dam, built in the Black Canyon of the Colorado River – the border between the states of Arizona and Nevada. It was built within five years, and cost $49 million – about 2.6 billion dollars today. The wall is long 379 meters, high 221 meters, and its thickness is 200m and 15m at the base of the tip. Over 2 million cubic meters of concrete was used for it and nearly 15,000 people have worked on this major project.
The contractors face a number of challenges related to the enormous size of the facility and harsh conditions of the construction site. Most of the technologies used at that time, were applied for the first time. Such as the possibility of uneven cooling and shrinkage of the concrete with such dimensions. Therefore it was decided to be poured blocks. The fitted blocks with a height of 1,5 m but a different size and are staggered. A system of tubes go through them, which is helping the cooling of the concrete. For the constant supply of concrete, over the canyon has been used system of ropes, which constantly passed 18-ton steel buckets, delivering to any part of the wall where it is needed. This is also an innovation for its time.
Behind Hoover Dam is Lake Mead. It stretches for 180km from the wall. It has an area of the impressive 640 square kilometers and the total storage reservoir volume is 35 cubic kilometers. The waters of the pond are not only used for irrigation of agricultural land and household needs, but also for electricity generation. The hydropower is at the foundation of the dam and its total capacity is 2,080 megawatts.