Hoover Dam

Hoover Dam was quite impressive. For miles before there were numerous high tension wires carrying electricity North to Las Vegas and when we were closer could see some going towards California. There was a 2-hour wait for the hardhat tour so we took the regular tour after watching the 1970's film about the building of the dam.

What a project!! It is amazing that this dam was originally to be built to control the flooding of the mighty Colorado River as it flows into the Imperial Valley in California where it floods every spring. Choosing the Black Canyon for the dam was only the first step. Building a city in which to house the workers and their families, choosing the 6 companies who would build the dam and the power station, deciding on the plans, arranging for the railroad tracks to transport the rock for cement and tools, building the roads for moving people, machinery, and everything else, and finally getting the workers assembled took lot of organization and planning. This was to be the largest dam in the world and is still the largest in the Western Hemisphere.

To divert the Colorado River while they were working on the dam, 4 large (56 ft wide) tunnels were built, two on each side of the canyon. This necessitated placing dynamite charges in the sides of the canyon, construction of roads on which to haul out the rock and debris, and the development of the "jumbo" (a special multiple rock drilling rigs mounted on 10-ton trucks with a battery of 30 rock drills mounted onto different platform levels) to create the holes for the dynamite. One of the old tunnels is shown emptying in to the Stoney Gate in the picture at the left. Before the pouring of any cement the existing riverbed had to be drilled down 135 feet to get rid of the silt and debris deposited over a number of years. Bedrock had to be found before the actual building of the dam could begin.

Notice that the dam is 660 feet wide at the bottom, 45 feet wide at the top and is 726 feet deep. The diversion tunnels were employed for emptying a spillway on either side of the dam and to drain some of the water from the Lake.

This is a picture of 3 of the 4 intake towers from the Arizona side of the dam. At the far left in the background is the parking structure for visitors and nearby is the visitors center. In the right background is a small cafeteria.

Notice that the intake towers are on the lake side of the dam, even though the picture above shows them on the other side.

These are the two intake towers on the Nevada side of Lake Mead. Notice that there are a number of boats in the distance. Boaters, fisherman and swimmers have all enjoyed the creation of this enormous Lake Mead Recreation Area which contains over 3,000 square miles of desert and water and over 550 miles of shoreline.

This is the view from the sidewalk at the top of the dam, looking down at the water flowing out of the generators. There are boaters down at the bend of the water, to give you an idea of the size of this structure.

The tour guide was quite good and conveyed a lot of knowledge to the 20+ numbers of people in the group. The first step was an elevator ride down 400+ feet to the bottom of the dam. At the bottom we were ushered into a room with the large generators, most of them were operating as seen by the lit bulb at their tops. Notice the arrows pointing to the unlit ones in the seond photo.

From there we went outside and saw the water spilling out of the bottom of the dam from the hydroelectric generator turbines. Compare this picture with the daigram at the top of the page. Note that the Canyon Wall Outlet Works are clearly visible as are the turbines.

We were able to get pictures at all of these areas. Back inside we went into another room where more explanation was given both verbally and graphically about the movement of the water and electrical power. A map similar to the one at the top was used to help the group understand.