Caltrans will switch traffic this week on both north and southbound lanes of Highway 101 as part ongoing construction work on the Marin-Sonoma Narrows project, officials said.Monday evening, northbound traffic will be shifted to the right, while southbound traffic will be detoured onto the median starting Wednesday night. The speed limit in the construction zone will be reduced to 55 mph, Caltrans said.

Only local traffic will be allowed to exit behind temporary safety barriers, and motorists are asked to be aware of local drivers merging onto Highway 101. Drivers should leave safe traveling distances between vehicles in front of them.