The Sonoma County Department of Transportation and Public Works (DTPW) proposes to replace the existing Freestone Flat Road Bridge, which is a two-span, steel-girder truss bridge over Salmon Creek, in the southwest portion of the County. The existing bridge would be replaced with a two-lane, cast-in-place pre-stressed concrete box-girder bridge supported on cast-in-drilled-hole piles at the abutments. The new bridge would be located parallel to and southeast of the existing bridge. The existing bridge would remain in service until the new bridge is complete, then disassembled and removed from the site.
Building the bridge on a new alignment requires the construction of new approaches on the east and west sides of the replacement bridge. Existing intersecting roads, including Scott Robin Road and a private driveway, would be modified to meet the new location of Freestone Flat Road as it approaches the bridge. Depending on the environmental review process, the property acquisition process, and the future availability of funding, construction of the Freestone Flat Road Bridge project is estimated to start in 2022.