King Ridge Road Bridge Replacement Project

Sonoma County is undertaking the replacement of the deficient one-lane bridge on King Ridge Road crossing Austin Creek, located north of Cazadero, California, with a new two-lane bridge constructed on a new alignment immediately upstream of the existing structure. The project will be completed over two construction seasons, with the new bridge and associated road realignment finished in the first season and the removal of the old bridge deferred to the second season, ensuring continuous traffic flow on the existing bridge throughout construction. The work is strictly limited to daytime hours, between 7 AM and 7 PM, to minimize disruption. All construction activities must comply with stringent environmental regulations to protect sensitive aquatic habitats, particularly salmonid species, and riparian zones, including adherence to seasonal work restrictions, such as prohibiting work near waterways from June 15 to October 15. Comprehensive mitigation measures are required, including a 2:1 wetland mitigation ratio achieved through native, weed-free vegetation restoration, installation of exclusionary fencing, silt fencing, and erosion controls, and strict adherence to Caltrans and AASHTO standards for bridge design and seismic resilience. Hazardous materials must be stored and handled at least 100 feet from waterways, with onsite spill cleanup kits and containment berms mandated, and all fueling operations must be conducted with daily equipment inspections to prevent leaks. The project is subject to federal and state environmental permits under the Clean Water Act, the California Endangered Species Act, and federal Endangered Species Act requirements, with formal coordination ongoing with NOAA Fisheries and the U.S. Fish and Wildlife Service for impacts to salmonids and the northern spotted owl. No net increase in greenhouse gas emissions, noise, or traffic is permitted, and all topsoil and backfill piles must be clearly marked and segregated on-site. The contractor is responsible for full compliance with these environmental mitigation conditions, which are enforced through the Sonoma County Permit and Resource Management Department, known as Permit Sonoma. No contract value, pricing, payment, or invoicing details are provided, and no traditional federal acquisition clauses or contract types are specified, as the documentation reflects a locally managed, environmentally driven project rather than a formal federal procurement. The primary point of contact for the project is David Walsh, Senior Environmental Specialist at Permit Sonoma, who oversees compliance and regulatory coordination.