Spirit Mountain, a sacred site to some Native Americans, rises in the southern part of the Lake Mead area. Ten thousand years ago, people hunted and gathered food from the desert. Later people learned to use yucca to make baskets and rope. They also used irrigation and grew crops.
By the 1700's native people began encountering European Americans when fur traders, explorers and a few settlers came into the desert.
In the mid 1800's, steamboats traveled up the Colorado River from Mexico. They brought more settlers and supplies into the Mojave Desert. Soon Mormons started towns along the Colorado, Virgin and Muddy Rivers.
After gold and silver were found in 1867, people crowded the towns and ferry crossings were built.
By the early 1900's, people wanted protection from from Colorado River floods.
The dam would regulate the river, generate electricity, and provide water for drinking and irrigation.
3,500 people worked on the dam and tourists came - and they are still coming. To see the dam and the new bridge, to play in Lake Mead and Lake Mojave, to hike. Spirit Mountain still draws native peoples seeking connection to their ancestors.
While the lakes hold more than 4 trillion gallons of water - this boat launch shows evidence of higher levels. The dark volcanic plateau is Fortification Hill.
The bathtub ring marks the historic high water level of 1983.
Jenny and me on the new bridge - it was really windy!
The bridge was the first concrete-steel arch composite bridge built in the United States, and its twin-ribbed arch is the widest of its kind in the Western Hemisphere. Forming a 1,060-foot-long, 277-foot-deep arch, the two ribs are joined laterally by Vierendeel steel trusses that add seismic protection. Each rib comprises more than 50 sections of concrete, each measuring 24 to 25 feet. Eight concrete vertical piers elevate the bridge deck above the arch structure, and a total of 36 steel girders weighing in at 50 short tons hold the whole thing up.
The total length of the bridge is 1,905 feet, making it the longest single-arch bridge in North America. A pedestrian lane on the north side provides visitors with the only way to see Hoover Dam from the bridge. At 880 feet over the Colorado River, it is the second-highest bridge in the United States and the highest concrete-arch bridge anywhere.
(https://www.asme.org/engineering-topics/articles/construction-and-building/hoover-dam-bridge-top-10-facts)
It was definitely FREAKY walking and standing on the bridge!
This disc marks the center of the bridge where you are standing in both Nevada and Arizona - both states also have different time-zones - Nevada is Pacific time-zone, Arizona is Central and does not recognize daylight savings.
This disc marks the apex of the bridge - it was a little past the state lines.
That's as far as we walked ... because it was FREAKY!!!
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