Auburn-Foresthill Bridge

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Auburn-Foresthill Bridge
Auburn, California, United States
730 feet high / 223 meters high
862 foot span / 263 meter span
1973

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The second highest bridge in the world upon its opening in 1973, the Auburn-Foresthill bridge is still among the 5 highest bridges in the United States. Although it is no longer even among the 20 highest bridges in the world, the 730 foot (223 mtr) high green giant still has the distinction of being the world’s highest cantilever bridge.

Ironically, the Auburn Foresthill bridge was built to cross a reservoir that never ended up being constructed! In the early 1970s, foundation work began on the 685 foot (209 meter) high Auburn dam east of Sacramento, California on the East Fork of the American River. Due to the huge reservoir that was expected to form behind it, engineers decided to reroute traffic across a tall bridge over the lake’s wide North Fork. After 3 years of construction, the huge cantilever span was opened in May of 1973. The dam, however, was permanently halted due to a series of unforeseen seismic studies, excessive cost overruns and other political and environmental concerns. While the bridge has become very useful to the small mountain communities in and around Foresthill, it ultimately would never have been financed without the planned reservoir. One casualty of the dam’s cancellation was an amazing cable stayed bridge that was planned for a site near Ruck-A-Chucky rapids that would have crossed the river several miles upstream from the Auburn-Foresthill bridge. Curving a full 180 degrees as it crossed the reservoir, the entire roadway would have been supported by a massive web of cable stays terminating into the mountainside. The complete lack of any towers or pier supports would have made it one of the most photogenic cable stayed bridges in the world. Hopefully the unique design will someday be used for a real bridge.

One of the most unique aspects of the Foresthill bridge is the open gap that was left between the two lanes in the center of the bridge. Originally designed as a 4 lane highway structure, two additional lanes can be added to the center of the bridge if an increase in traffic ever arrives. The current lanes are unusually wide at 20 feet (6 mtrs). The bridge is very pedestrian friendly with walkways on both sides of the bridge offering spectacular views of the American River gorge. The great accessibility of the bridge has also made it popular among BASE and bungee jumpers. Auburn-Foresthill bridge is a near twin of the much less known Phil G McDonald or Glade Creek bridge near Beckley, West Virginia. From an engineering standpoint the only major difference between the two is the West Virginia span is a continuous truss instead of a cantilever. The California span is only about 10 percent bigger in size and height. Much of the Auburn bridge’s visual power comes from the two massive concrete piers that rise 403 feet (123 mtrs) from the ground to apex or 520 feet (159 mtrs) from ground to roadway. They were the highest bridge piers in North America for many years until Mexico’s 1993 Mezcala bridge opened with a 541 foot (165 mtr) tall pier. In 2012, Mexico will open the second and third highest bridge piers in the world when the El Carrizo and San Marcos bridges are completed. Only the Millau bridge in France will have a higher pier.

A visit to the Foresthill bridge would not be complete without a visit to the other bridges you can see as you look down into the gorge. The most interesting of these being the abandoned Mountain Quarry railroad bridge, sometimes referred to as the “No Hands Bridge”. A short hike from route 49, the 80 foot (24 mtr) high, triple concrete arch was originally built in 1912 by the Pacific Portland Cement Company to provide access to a limestone quarry. The rail line was a 10 mile (16 km) spur from the Southern Pacific mainline in Auburn. Around 1939 the line and bridge were abandoned. The integrity of the structure was tested in December of 1964 when the Hell Hole Dam broke upstream of the bridge. The ensuing flood took out the road bridge just upstream of the railroad bridge. The remains of this bridge can still be seen in the river. Auto traffic was then rerouted across the railroad bridge until a replacement span could be built for the road. Today the former railroad bridge is part of the Western States Pioneer Express Recreation Trail. The “no hands” name refers to a time when there were no handrails on the bridge, prompting a horse rider to cross the bridge without holding her reins.


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Auburn-Foresthill Bridge Elevation


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Image by Eric Sakowski / HighestBridges.com


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Image by Eric Sakowski / HighestBridges.com


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Image by Eric Sakowski / HighestBridges.com


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Image by Eric Sakowski / HighestBridges.com


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Image by Eric Sakowski / HighestBridges.com


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Aerial image by Eut Tileston.


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Auburn-Foresthill Brdige as it might have looked under 600 feet (183 meters) of water. Aerial image by Eut Tileston.


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Designed to handle 4 lanes, the center two were never built since the old route 49 below still carries the majority of traffic through the river gorge. Image by Eric Sakowski / HighestBridges.com


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Image by Eric Sakowski / HighestBridges.com


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Image by Eric Sakowski / HighestBridges.com


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Image by Eric Sakowski / HighestBridges.com


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Image by Mark Ketchum.


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Image by Mark Ketchum.


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Image by Mark Ketchum.


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Image by Eric Sakowski / HighestBridges.com


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Call boxes were added in later years to help reduce the once-a-year suicide rate. Image by Eric Sakowski / HighestBridges.com


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2004 bridge memorial. Image by Eric Sakowski / HighestBridges.com

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