Monday, July 16, 2012

Hoover Dam

Jill's Journal: Surely everyone has seen pictures of Hoover Dam, such as the one above borrowed from a government site. But to truly appreciate it, you have to see it. It is said the marvel that is Hoover Dam is the greatest engineering feat of mankind since the great pyramids of Egypt.

Spanning the border of Nevada and Arizona, it was originally called Boulder Dam. The name was officially changed in 1947 in honor of the 31st president, Herbert Hoover, who was a strong supporter of the project.

Today, in addition to helping meet the water needs of over 20 million people, Hoover Dam generates enough low-cost hydroelectricity to serve 1.3 million people. California is allocated 56% of the power, Nevada 25%, and Arizona 19%.

The water behind the dam is Lake Mead, the largest manmade body of water in the Western Hemisphere. It has an astounding 550 miles of shoreline with a surface area of 156,800 acres. I snapped this picture from the Arizona side.

Here’s a closer picture of one of the four intake towers from the Nevada side.

This is one of those same massive intake tunnels from 574 feet below the surface. Standing in the room/platform above it, one can feel the floor vibrating from the millions upon millions of gallons of rushing water below.

The girls learned a little about the path the water takes from our guide, Fred.

And then it was into the power plant itself. There are two, one on the Nevada side and one on the Arizona side.

Here’s the power plants from above. They’re the “arms” that stick out below the dam. A tour inside the dam itself can be taken, but two of our three kids were too young for the safety cut-off.

Without a fancy camera lens, this was the best I could do from our vantage points of the dam. It’s such a massive structure; indeed, the road between Nevada and Arizona goes right over it…or used to until it was diverted to a bridge spanning the canyon after 9/11. I remember being able to stop on the side of the road and peek over the dam. Now one can still drive over the dam but must pass through a security checkpoint first.

Some fun statistics: Hoover Dam is 726 feet high, 1,244 feet long, 45 feet thick at the top, 660 feet thick at the bottom, and contains 3.25 million cubic yards of concrete. In fact, there’s so much concrete in Hoover Dam that it should take 125 years to cool such a project as concrete gives off heat as it cures. To get around this challenge, designers built the structure in five foot tall blocks and built an innovative refrigeration plant right into the dam.

Construction began in 1931. Hoover Dam was finished and dedicated in 1935, with the power plants finished the following year. Around 16,000 people worked on the project with 96 people dying on site. The crew worked 24 hours a day, 363 days a year. Amazingly, they finished the dam under budget and more than two years ahead of schedule. I can’t imagine that happening in this day and age!

After passing through the power plants, the Colorado River continues on its merry way.

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