The Bear River Bridge is located in Nevada County in the U.S. state of California. In its time, it was the highest railway bridge in the state. The railway cantilever bridge spans the Bear River.
History
It was built on the line of the Nevada County Narrow Gauge Railroad. From the surface of the water, at an average stage, up to the track is 200 feet (61 m). The total length is about 900 feet (270 m), and at the time of construction there were no approaches, the opposite banks being abrupt. The pier foundations were built of reinforced concrete, requiring more than 500 cubic yards. The piers and superstructure are of structural steel, of which about 500 tons were used. All the steel material was furnished by the American Bridge Company of San Francisco, and the constructing contractors were Shattuck & Edinger Construction Company, also of San Francisco. The total cost of the bridge was approximately US$70,000. The engineering involved much difficulty—principally due to the unusual height of the structure. At the beginning of the work the contractors stretched a 2.25 inch diameter steel cable from bank to bank more than 200 feet (61 m) above the Bear River, and 1,000 feet (300 m) long. By means of this cable all of the structural steel material required, as well as the concrete, were hoisted and conveyed by a trolley to the required point and lowered to the proper position. It took about six months to complete construction. Only a small force of men were employed and the work necessarily progressed rather slowly. This railway bridge is on a 1 mile (1.6 km) long cut-off which shortens the road 2 miles (3.2 km), and also eliminates two long wooden bridges, each 100 feet (30 m) high, and one 400 feet (120 m) tunnel. The total outlay to the Nevada County Narrow Gauge Railroad Company (including the steel bridge) for these Improvements reached nearly US$140,000.