For information about the Humboldt Bay Bridge testbed, please see the testbed managers' webpage. This page contains supplementary and summary information.
The subject bridge is the Middle Channel Bridge, one of three crossing Humboldt Bay on California State Route 255. It is located at 40.814N x 124.158W (location of CSMIP instrument 89735). The other two bridges are the Eureka Channel Bridge (40.809N x 124.154W, CSMIP 89736) and the Somoa Channel Bridge (40.822N x 124.169W, CSMIP 89686). The bridge (no 04-0229) is a 330m, nine-span composite bridge built in 1972. In 1992, it carried average daily traffic of 4,600 to 15,800.