By harnessing the mighty Colorado River, the concrete structure on the Arizona-Nevada border provided electricity to the Southwest, helped irrigate 2 million acres and fueled the development of Los Angeles, Las Vegas and Phoenix. Here's a look at the dam and its construction. Hide Caption. This image shows Black Canyon on the Colorado River before work started. During construction, the water was diverted around the dam site through four 50 feet in diameter tunnels, drilled through the canyon walls on each side of the river.
Damming of the river created Lake Mead, now a popular recreation spot for boaters. A man stands inside part of one of the dam's enormous turbines. Construction of the dam took less than five years and was completed in The dam was built in vertical columns of blocks that varied in size from about 60 feet square at the upstream face of the dam to about 25 feet square at the downstream face.
An estimated blocks make up the dam. Adjacent columns were locked together, like a giant Lego set, by a system of keys. A Union Pacific Railroad train, carrying sections of the dam's steel gates, pulls out of Los Angeles en route to the dam site. Each gate section weighed about 36 tons, and when an entire gate was assembled it weighed 2, tons. Workers in construct a retaining wall to support the road leading over the top of the dam.
Before the dam could be built, the government had to create a town, Boulder City, to house construction workers; build a seven-mile paved highway from Boulder City to the dam site; and construct 33 miles of railroad from the Union Pacific main line in Las Vegas.
When Hoover Dam was finished, it was the tallest dam in the world at feet, although that record has since been eclipsed. The construction of Boulder Dam, later renamed as the Hoover Dam.
Structure of dam erected into canyon. Equipment in tunnels. Giant cranes in operation. Concrete arch-dam in the Black Canyon. Traffic moves on highway over dam. Boat in Colorado River. One funny thing is the change in time zones as you walk from one side of the dam to the other. In fact, there are large clocks on two of the intake towers to let you know that you are on Pacific Standard Time on the Nevada side of the dam and Mountain Standard Time on the Arizona side.
The state line actually runs right through the center of the dam. There are plenty of other great views from points all around Hoover Dam. I also enjoyed the artwork designed to honor its builders.
All of these tributes really brought that period in history alive for me. Plus, its construction was a real feat considering the place—a barren, unforgiving desert. So believe me when I say that in this day and age, Hoover Dam is still a marvel and one that you should not miss!
This magnificent engineering feat is the work of man. Not to diminish the amazing wonders found in nature, but the construction of Hoover Dam is a gigantic tribute to human ingenuity. A visit here may even inspire a belief in your own ability to accomplish whatever you put your mind to. When you walk onto Hoover Dam, there is a point in the middle through which the state border runs.
The past 12 months have been among the driest on record across the Colorado River Basin. But the demands for water downstream from Hoover Dam continue.
The reservoir has declined more than 16 feet over the past year and is forecast to fall about 9 feet more by the end of this year.
The latest projections show that by the end of , Lake Mead will decline below an elevation of 1, feet, far below the threshold — 1, feet — for the federal government to declare a shortage. The Colorado River naturally cycles through wet and dry periods. But over the past 22 years , the watershed has had 17 dry years, Bernardo says, and only 5 years with above-average or wet conditions. With climate change, hotter temperatures have been evaporating more moisture off the landscape and leaving less flowing in the river and its tributaries.
But some scientists have estimated the river could lose roughly one-fourth of its flow by as temperatures continue to rise, and that for each additional 1 degree C 1. In , representatives of Arizona, Nevada and California agreed under a deal called the Drought Contingency Plan to share in water reductions through to reduce the risks of Lake Mead falling to critically low levels.
The agreement calls for progressively larger cutbacks if Lake Mead continues to drop below lower trigger points in the coming years. If the reservoir drops below 1, feet, California would start to take cuts. And Mexico is already contributing by leaving some water in Lake Mead.
While the latest agreement is intended as a temporary stopgap measure, officials from the seven states that depend on the river are preparing to negotiate new rules for managing shortages after And those talks promise to be tougher. In the meantime, he says, the bureau's responsibilities in managing the dams and water deliveries remain the same.
Leaving the room overlooking the lake, Bernardo leads us along the sidewalk and into a tower, where golden elevator doors roll open. Bernardo is 35 and has worked for the Bureau of Reclamation for nearly a decade, including the last two years as river operations manager. According to the Bureau of Reclamation, Hoover Dam contains enough concrete to build a sidewalk 4-feet wide around the entire Earth at the equator.
Bernardo is steeped in numbers and rattles off details about river flows, the dam, the volumes of water released and the amounts of hydroelectricity generated. With higher lake levels, Hoover Dam's normal capacity is 2, megawatts, he explains, generating enough power per year to supply approximately , average households.
With every foot the lake declines, about 6 megawatts of power-generating capacity is lost. The lowest level at which Hoover could produce power is about feet, with an expected capacity of megawatts. If the lake were to fall below that point — a scenario the existing rules are geared toward avoiding — the dam would no longer be able to generate power.
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