Marsh Creek Road Bridge Replacement Project

Location

12801 Marsh Creek Road, Clayton, CA 94517

City or County Responsible for Project

Contra Costa County

Category

Bridge: Efficient and Sustainable Bridge Maintenance, Construction and Reconstruction Projects

Author

Neil Leary

Organization

Contra Costa County Public Works

Address

255 Glacier Drive, Martinez, CA 94553

Phone

925-313-2278

Project Description

The goal of the Marsh Creek Road Bridge Replacement Project is to replace the existing structurally deficient and geometrically obsolete steel girder bridge in the valley near Mount Diablo State Park with a wider, concrete girder bridge that is 100 year flood compliant and built to current safety standards, while accommodating current heavy traffic and minimizing impact to local stakeholders and ecosystem. The replacement bridge was constructed in several stages as it overlaps the existing bridge over steep creek bank slopes. The project also required the construction of a wider roadway alignment, soldier pile retaining wall, temporary soil-nail shoring walls, water main pipe relocation attached to the bridge, and rock slope protection and coir block embankment stabilization. The project was presented with the many challenges including: (1) Maintaining two-way 6000 ADT traffic during construction; (2) accelerated construction schedule to complete the project in one construction season instead of two; (3) complex logistical and staging needs due to narrow construction laydown area; (4) minimizing impact to many protected species on site; (5) safety management during highly coordinated and complex construction; and (6) multi-stakeholder coordination and resolving conflicting demands and managing community relations. Addressing these challenges and safely delivering the project on-time and within budget required a creative and methodical approach, and competency and cooperation of all of team members throughout the project. The project management/design/construction team, consisting of Contra Costa County Public Works Department, Substrate, Mark Thomas & Company, LSA Associates, and Bridgeway Civil Constructors, developed intricate and comprehensive work plan, incorporating innovation such as: (1) adopting a convenience-focused traffic control plan that used short, staggered road closures lasting no longer than 15 minutes each to accommodate crane and truck operation for girder installation; (2) shortening construction time by utilizing precast concrete girders, high early strength concrete with accelerants, and soil-cement in lieu of traditional backfill, working on Saturdays/longer shifts, and eliminating a construction stage; (3) reducing bridge deck closure cure settlement time from 60 days to 15 days; (4) installing temporary exclusion fencing to limit exposure to wildlife within the jobsite; (5) installing temporary water stream diversion closed system to ensure wildlife in the creek was not affected by construction; and (6) constructing a 22-feet all temporary shoring wall to protect live traffic from adjacent deep excavation. The Marsh Creek Road Bridge Replacement Project team ultimately overcame all of the challenges and delivered a structurally sound replacement bridge on time and on budget that improves driver and bicycle safety and maintenance requirements, while enhancing the neighboring creek embankment and environment.