Hickman Road over Tuolumne River Bridge Replacement
Location
Hickman Road at the Tuolumne River near Waterford, CA
City or County Responsible for Project
Stanislaus County
Category
Bridge: Efficient and Sustainable Bridge Maintenance, Construction and Reconstruction Projects
Author
David Leamon
Organization
Stanislaus County
Address
1716 Morgan Road, Modesto CA 95358
Phone
(209) 525-4151
Supporting Documentation
Project Description
The former scour critical and seismically deficient Hickman Road Bridge, originally built in 1964, provided a vital connection between the City of Waterford and the Community of Hickman, but was subject to closure during high flow events in the Tuolumne River due to the ongoing degradation of the river channel and undermining of the pier foundations. Because of its unreliability, Stanislaus County spearheaded this project to replace this regionally important bridge.
The replacement bridge has been founded on deep pile foundations to address the degradation of the Tuolumne River channel and improve the reliability of the connection between the two communities. The new bridge provides dependable access for first responders, residents, schools, and businesses. The new bridge also provides safe access to pedestrians and cyclists which was not afforded by the old bridge.
This project also made local improvements including enhancements to the adjacent City of Waterford River Park and River Park Trail. The portion of the River Park Trail directly below the bridge was improved by revising the vertical profile to meet ADA standards making the trail and park more accessible. Natural stacked rock aesthetics were provided on the replacement bridge and trail supporting retaining walls to remove the concrete monolith look of the former bridge and improve the look and feel of the park and trail. The replacement bridge also carries a new water force main across the Tuolumne River into the Community of Hickman to improve the reliability of Hickman’s water system and provide suitable fire flow protection.
Impacts to the natural environment are inevitably expected when it comes to bridges crossing rivers and creeks. To mitigate impacts to the Tuolumne River channel, the design set the replacement bridge on an alignment upstream of the former bridge to reduce impacts to native plants and used longer spans than the old bridge to reduce the number of piers and pier foundations within the Tuolumne River channel. The design of the replacement bridge also incorporated bat houses for the estimated 6,000 bats that had created homes on the old bridge. In addition, as part of the removal of the old bridge, the existing bridge scour counter measures were removed, resulting in the removal of nearly 500 tons of concrete, and the Tuolumne River channel was restored to natural grades using existing river rock and gravels.
Construction of the new bridge is complete. The new Hickman Road Bridge provides a reliable connection between the City of Waterford and Community of Hickman; a safer crossing for vehicles, pedestrians, and bicyclists; a structure that meets current seismic criteria and addresses the on-going Tuolumne River channel degradation; a new regionally important waterline across the Tuolumne River; habitat for 6,000 bats; a restored Tuolumne River channel; and an enhanced look and feel to River Park and the River Park Trail.
