One of the America’s favorite cities would not exist as we know it today without Hoover Dam. California and other Southwestern States neither. Prices of vegetables in US would be higher. Hoover Dam is the heart of Southwest, providing clean energy, water, protection against floods and recreation to millions of people.
Las Vegas Strip-Hoover
Dam. 35 miles and 45 minutes ride (Google Maps).
Colorado River flows along a 1,400 miles course from the Rocky Mountains
to the Gulf of California (Mexico). It had flowed free for 40 million years,
until the human being dominated it in 1935.
First settlers suffered the seasonal changes of the River. It was a
love-hate relation from the very beginning. Agricultures need the water that
Colorado River provides, and settled in its low farmlands. It was like an Oasis
in the desert. But in late spring and early summer, the snow of the Rocky
Mountains melted causing massive floods and destruction. During late summer and
fall, the river dried to a trickle, too low to divert.
People from the East, especially North East, did not see this as a
Federal issue, so no solution was provided. In addition, the share of the water
involved seven States, what made the problem bigger.
In 1922 a representative of each State signed an agreement, which
divided the Colorado River in two basins, upper and lower half. It paved the
way for the Hoover Dam.
The upstream face of Hoover
Dam. Looking downstream from the Arizona rim (Own Photo).
Construction began in 1931. It was the zenith of America’s Great
Depression, when the workers were desperate for a job with they could feed their
families. The first three weeks after project was announced, local job office
received 12,000 applications. In the beginning, workers and their families
lived in tents around the construction place and the river. 21,000 men worked in
the Hoover Dam and lived with their families in poor living conditions and extreme
temperatures.
It was dessert: no cities, no water supply, no roads nor any
infrastructure, and the nearest railroad was in a small unknown town called Las
Vegas 35 miles far away.
The live conditions were so bad, that the company had to build everything,
even a new town, Boulder City. The city was well designed and constructed, as a
symbol of prosperity in the Great Depression days.
The downstream face of
Hoover Dam. Looking upstream from the Arizona rim (Own Photo).
Construction:
Phase 1: Four tunnels were constructed to divert Colorado River, making
a dry area where the dam could be placed. Rock excavated from the tunnels was laid
into two temporary coffer dams to divert river to the tunnels. Tunnels opened
in November 1932.
Phase 2: 2.6 million cubic meters was poured to construct the dam.
Two huge manufacturing concrete plants were built on the construction
side for providing this huge amount of concrete. But engineers had a big worry:
Heat.
When we mix the ingredients of concrete: water, sand, rocks and cement,
there is a chemical reaction, which generates internal heat slowing down the curing
process. The larger you pour, the longer it cures. So they decided to build
Hoover in a series of interlocking blocks of 5 feet height, but that was not
enough. To cool the concrete more, the engineers disposed a system of pipes
crossing the blocks of concrete. They pumped cold water in the pipes, so the
concrete cooled down.
To make the construction even faster, they organized a competition between
the different pouring teams, and it worked! 8,000 thousand cubic meters of
concrete were poured each day.
In January 1935, arch was completed, and in September 1935 the very last
concrete was poured, when President Franklin D. Roosevelt dedicated the Dam. The construction of the power plant finished
one year later. The Lake Mead needed 6 years to be completely filled, but the
generation of electricity began before. In 1939 the Dam’s power plant became
the largest hydroelectricity facility in the world. 112 workers gave their
lives to make this dream possible.
Hoover Dam Power plant
(Own Photo).
Facts:
Location: Colorado River. Between Nevada and Arizona. 35 miles from Las
Vegas.
Cost: $49 million ($811 million today, 6 Gareth Bales)
The Dam:
Type: Arch gravity.
Height: 726.4 feet (221.3 meters, half
of the Empire State Building height)
Crest length: 1244 feet (379.2 meters)
Crest width: 660 feet (201.2 meters)
Volume of Concrete: 3.25 million cubic yards (2.6 million cubic meters)
The Powerplant:
Commercial generating units: 17.
Nameplate capacity: 2800 megawatts (enough
to serve 1.3 million people)
Energy Distribution: California: 55.91%, Nevada: 25.14%, Arizona: 18.95%
Lake Mead:
Shoreline: 550 miles (885 km, 1.44
times Delaware shoreline)
Capacity: 28,254,000 acre-feet (34.85 billion cubic meters, enough to cover all the State of New York with 30 cm of water)
Maximum depth: 498 feet (151.4 meters)
Surface area: 156,800 acres (63,455 hectares, almost 89,000 soccer pitches)
Length when full: 110 miles (177 km)
More info:
Info and Tickets: http://www.usbr.gov/lc/hooverdam/index.html
National Geographic Megastructures. Hoover Dam:
http://www.youtube.com/watch?v=pBJq4W9V4Lw
Wikipedia: http://en.wikipedia.org/wiki/Hoover_Dam
Old Photos of Dam’s Construction: http://www.ecommcode.com/hoover/hooveronline/hoover_dam/before/toc.html
Hoover Dam reinvented: http://channel.nationalgeographic.com/channel/man-made/videos/a-new-hoover-dam/
