The Hoover Dam Bridge was mandated as a priority one project after 9-11, since the Hoover Dam is the primary conduit between Phoenix and Las Vegas, and a part of the Mexico to Canada Trans-America International Highway. A bridge had been in the planning for decades to alleviate congested traffic slowing national and international traffic between Arizona and Nevada.
Prior to 9-11, truck traffic would cause congestion in Boulder City. This was midway through the Las Vegas boom, with fewer tourist and locals in both Greater Las Vegas and the booming Phoenix Metro.
A bipass highway was promised, but funding and constuction became a much lower national pririty, so that highway has yet to begin as the bridge nears opening, leading to fears of congestion, crime and pollution for growth limited controlled Boulder City and the wild life reserves of the El Dorado Valley.
The bridge also changes the fact of the dam and historic views. Walls along the highway will make it impossible to see the dam or the views themselves as you cross the bridge, unless you are young enough, strong enough, and willing to take the walking and bike baths below the roadway.
The bridge itself is almost as great a construction wonder as the dam was itself. It will be one of a kind, state of the art, and built far faster than any bridge even approaching its type. The bridge will carry a certain archutectual beauty.
A thank you for Nevada SAG member Heart Sharpe and her friend Sharon Lee for the article and photos.
THE WIDER VIEW: Taking shape, the new bridge at the Hoover Dam
Creeping closer inch by inch, 900 feet above the mighty Colorado River , the two sides of a $160 million bridge at the Hoover Dam slowly take shape.
The bridge will carry a new section of US Route 93 past the bottleneck of the old road which can be seen twisting and winding around and across the dam itself.
When complete, it will provide a new link between the states of Nevada and Arizona . In an incredible feat of engineering, the road will be supported on the two massive concrete arches which jut out of the rock face.
The arches are made up of 53 individual sections each 24 feet long which have been cast on-site and are being lifted into place using an improvised high-wire crane strung between temporary steel pylons.
The arches will eventually measure more than 1,000 feet across. At the moment, the structure looks like a traditional suspension bridge. But once the arches are complete, the suspending cables on each side will be removed. Extra vertical columns will then be installed on the arches to carry the road.
The bridge has become known as the Hoover Dam bypass, although it is officially called the Mike O'Callaghan-Pat Tillman Memorial Bridge, after a former governor of Nevada and an American Football player from Arizona who joined the US Army and was killed in Afghanistan.
The foot bridge access to the new bridge is described in a story in the July 16, 2010 Las Vegas Sun:
The dam was started in 1931 and used enough concrete to build a road from New York to San Francisco . The stretch of water it created, Lake Mead , is 110 miles long and took six years to fill. The original road was opened at the same time as the famous dam in 1936.
An extra note: The top of the white band of rock in Lake Mead is the old waterline prior to the drought and development in the Las Vegas area. It is over 100 feet above the current water level.
For additional information visit the Federal Bureau of Reclamation, located in the first historic major government buiding at the apex of the city design in Boulder City.
Some of the material above first published in this blog January 22, 2010
Remainder from information gleaned since and from a "Las Vegas Sun" July 16th feature story.