El Dorado County: State Route 50 across Weber Creek - Old & New
A study several bridges that cross Weber Creek, a 12 mile long tributary of the South Fork of the American River that runs through Diamond Springs, California.
Diamond Springs took part in much of the 19th century development that helped to create California. The wagon route used by the first pioneers went through town as well as the Pony Express and parts of the first Transcontinental Railroad. Today, two major routes go through Diamond Springs, State Route 49 and State Route 50. More information on the history of transportation through Diamond Springs can be found on Wikepedia.
Today's bridge was the original State Route 50 crossing over Weber Creek, just half a mile west of the previously studied Forni Road Bridge (the yellow pushpin in the Google earth photo below). In 1963, parallel, steel girder, four span bridges on multicolumn bents were built beside it, but they left the original bridge (built in 1938) in place. State Route 50 keeps getting more and more traffic as El Dorado County continues to grow and so new lanes are being built, but so far the original bridge has been preserved.
The old State Route 50 Bridge over Weber Creek is dwarfed by the newer highway bridges. It looks like the newer bridges are on taller embankments, perhaps because they are raised above the 100 year flood (or maybe they are just longer and going over a deep valley).
The old State Route 50 Bridge is a five span haunched girder bridge with in-span hinges at the first and fifth spans. I think the bridge might have been rehabilitated at some point. Note the interesting roller bearings in the photo below. Those don't look like they were built in 1938. The bridge is now 75 years old, which makes it eligible for designation as an historic place. However, I couldn't find any reference to this bridge. It looks like a new end diaphragm and new wingwall (and perhaps a new abutment) were cast recently, perhaps because of the widening of the newer bridges? http://www.bphod.com/2013/02/el-dorado-county-californias-bridges_12.html
This bridge reminds me of the Forni Road Bridge across Weber Creek that we previously studied since it's pretty much of a slab bridge with supports at the sides. However, this bridge has more diaphragms, which the Forno Road Bridge was able to do without. Another strange thing is the building paper falling out of the expansion joints. It seems strange that paper would still be coming out of a 75 year old bridge.
Well, this old bridge presents more questions than answers. Perhaps someone familiar with the old highway can enlighten us? http://www.bphod.com/2013/02/el-dorado-county-californias-bridges_13.html