Highway 37 closure scheduled for El Niño flood preparations

Caltrans will close a section of Highway 37 in the North Bay for 55 hours to prepare for potential heavy rains and El Niño weather conditions. The closure affects the roadway between Mare Island in Vallejo and Sears Point in Sonoma County, beginning at 10 p.m. on Friday, Oct. 23, and lasting until 5 a.m. on Monday, Oct. 26.

During this period, crews will demolish the median and install K-rail to shift all traffic into the westbound lanes. Workers will also raise portions of the eastbound lanes by three feet to mitigate flooding concerns. To prepare for the main closure, westbound lanes between Mare Island and Sears Point will also be closed from 7 p.m. Thursday through 4 a.m. Friday.

Caltrans officials noted that the resulting detours may exceed one hour due to a lack of redundant routes in the North Bay. Drivers are advised to use Highway 29 and Highway 12/121 as alternate routes. Additional supplemental closures are planned for the weekend of Nov. 13 to Nov. 15, though all work remains dependent on weather conditions.