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  5. State Route 12/121 in Schellville to reopen Tonight, October 27, As Railings Replacement Project Ends on the Arroyo Seco Bridge

State Route 12/121 in Schellville to reopen Tonight, October 27, As Railings Replacement Project Ends on the Arroyo Seco Bridge

Published:

Closure scheduled for thirty days opens three days early

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Sonoma County - Caltrans will reopen State Route 12/121 tonight, October 27, at approximately 10:00 PM, in the Sonoma County community of Schellville, as Caltrans finishes replacing the weather-worn and outdated bridge railings on the Arroyo Seco Bridge spanning Schellville Creek.

Map of State Route 12/121 Arroyo Seco and Yellow Creek Bridge Rail Replacement.
Detour map for Thirty-Day Closure of State Route 12/121 in Schellville, Sonoma County, to Replace Railings on Arroyo Seco Bridge. Westbound traffic will be detoured onto Napa Road to Eighth Street, then back to Route 12/121. Eastbound traffic would follow this detour route in reverse.

Caltrans had scheduled a 30-day closure from October 1 to October 31; however, the construction team reopened the bridge three days early.

The reopening of the highway will be welcome news to motorists who have been detoured around the closure via 8th Street E and Napa Road.

The Arroyo Seco Bridge was built in 1923. The former bridge railings, which served as guardrails, were original and were replaced to meet current safety standards.

Before construction started, Caltrans met with first responders, Sonoma County officials, and the Sonoma County Transportation and Climate Authority to consider the results of a traffic study comparing a full closure to one-way traffic control. Caltrans opted for a full closure.

The full closure provided more working room for construction crews and required a 30-day closure, whereas the one-way traffic control alternative would necessitate a much longer partial closure due to the lack of working room. First responders were unanimous in their preference for the closure with the shorter duration.

The replacement of bridge railing on the Arroyo Seco Bridge is half of a two-bridge project. Caltrans has scheduled bridge railing replacement on the nearby Yellow Creek Bridge on Route 121 to begin on November 3, 2025.For more information and update go to the project webpage: 121 Arroyo Seco and Yellow Creek Bridge Rail Replacement | Caltrans

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Or call 1-800-472-7623, 1-800-427-ROAD for state highway conditions statewide.