The $83.6 million Simmerly Slough Bridge replacement project along Highway 70 is more than halfway done and significantly ahead of schedule, according to the California Department of Transportation.
Work to the bridge has been ongoing since September 2019. The current structure no longer meets current design and seismic safety standards and the area beneath the bridge experiences scouring to the piers and abutments during high water events. Caltrans hired MCM Construction to build a new bridge adjacent to the old one, which is the same company in charge of building the new Fifth Street Bridge between Yuba City and Marysville.
Cameron Knudson, project manager for Caltrans, said crews worked during the winter months and have made a tremendous amount of progress.
“The bridge will meet current seismic, safety and design standards,” he said. “The new bridge is wider than the existing bridge and will feature 8-foot-wide shoulders, a 6-foot-wide sidewalk that is separated from traffic by a concrete barrier, and a 12-foot-wide center median. Upon completion the bridge is planned to be striped for three lanes (one lane in each direction with a 12-foot center median/left-turn pocket) but is being built to accommodate two lanes of traffic in both directions for the future.”
Currently, crews are finishing setting up the temporary support structure of the bridge, called falsework. That will support the structure when the concrete is poured for the section under the deck and for the bridge deck.
“Within a few weeks, the contractor will start to pour concrete for the first time,” Knudson said. “The pour will be for sections under the bridge deck. After that work is completed, the contractor will start pouring concrete for the bridge deck.”
To date, about 350,000 cubic yards of dirt has been moved — enough to fill 106 Olympic-sized swimming pools. About 9,000 cubic yards of concrete will be poured for the project once all is said and done.
“We anticipate a substantial amount of work will be completed this season and are targeting completion in 2021,” Knudson said. “…We want to remind motorists about the construction zone speed reduction from 55 mph to 45 mph and for them to be work zone alert.”