Starting Monday and lasting about three months, Highway 1 will be down to one lane 24/7 as Caltrans builds a retaining wall near Bodega Bay.

Although Caltrans vows to keep traffic delays to a minimum, it’s pretty likely that during summer weekends the backup could get ugly, so be prepared.

The work is being done along about a 500-foot stretch of Highway 1 just west of Bodega Highway, Caltrans spokesman Robert Haus said.

The retaining wall is necessary because the winter’s heavy rains left the stretch susceptible to mud and rock slides, he said.

Traffic in each direction on Highway 1 will be controlled by traffic lights on each end of the project.

“Drivers are advised to expect moderate delays and to allow extra travel time,” Haus said in a statement.