|December 2013 (38.71462 Degrees, -122.26072 Degrees) Knoxville Road Bridge
The county engineer was Edward Ball, the designer was Hal Sams, and the builder was Harry Thorsen. It says something about how much pride Napa County has in their bridges that they usually include a plaque with the names of the people responsible for each bridge.
The bridge has deteriorated a great deal since it was built in 1920 and so they're holding a public hearing to post weight restrictions on the bridge. It carries about 250 vehicles a day and has a sufficiency rating of 25.
There is an abandoned arch bridge nearby over a tributary of the Eticuera Creek but I wasn't able to find it. Fortunately, Craig Philpott has a pohto of it in the Bridgehunter Website.
Napa County, California Bridges: Knoxville-Berryessa Road Bridge across Eticuera Creek by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.