Spanish Creek Bridge taking shape
The $15 million Spanish Creek Bridge is scheduled to open for traffic in June 2012.
It is one of just three arched bridges constructed in California in the last 50 years, according to Caltrans.
Concrete is pumped 180 feet up to the arch from the mixing truck. Photos by Shannon Morrow
When completed, the arched bridge will have a span of 698 feet.
Caltrans said the new bridge would be much stronger and wider than the old one. It is being built to withstand the largest earthquakes recorded in the area and will be certified to hold heavier loads. The old bridge could not handle an oversized, 15-axle tractor trailer. The new Spanish Creek Bridge will be able to handle two of those vehicles at the same time.
The new bridge will have two 12-foot lanes with 8-foot shoulders. The old bridge has just 6-inch shoulders.
The new bridge is being constructed on Highway 70, about nine miles west of Quincy, beside the old bridge that was built in 1935.
In this Sept. 8 photo, workers pour some of the 2 million pounds of concrete that will be used to construct the bridge’s arch. About 270 yards of concrete are used for each of the nine sections of the arch. One section is completed each week. The pour was in its fourth week when these photos were taken.
Workers test the concrete before it is sent up to the arch. The concrete, which comes from White Cap in Portola, is designed to support 6,000 pounds per square inch.
40 construction workers secure the rebar used to support the concrete.
Water is pumped from Spanish Creek to help cool the concrete. The process borrows the water, which is returned to the creek less than 1 degree warmer than when it left and just as clean.
Concrete is mixed before being used on the arch.
The pouring begins about 1 a.m. Thursdays and is usually finished by noon. About 27 yards of concrete are added to the arch each hour. The last concrete is expected to be added about Oct. 20. After that, the arch will be a free-standing structure.