The first of two closures on a stretch of state Route 163 will begin Wednesday night so crews can remove temporary construction supports on the Cabrillo Bridge.
Southbound state Route 163 will be closed from Interstate 8 to the Laurel Street overcrossing between 10 p.m. and 5 a.m. Thursday, as will the connectors from eastbound and westbound Interstate 8, and Robinson Avenue and Washington Street on-ramps, according to Caltrans.
The off-ramps from the state highway to Washington Street and University Avenue will also be closed.
Motorists will be detoured onto westbound Interstate 8, then southbound Interstate 5 and onto northbound state Route 163.
Northbound state Route 163 from downtown to Washington Street and the connectors from Interstate 5 will be closed from 10 p.m. Thursday to 5 a.m. Friday.
Drivers will be able to head north on 11th Avenue to northbound Interstate 5, then to eastbound Interstate 8, which leads to state Route 163, according to Caltrans. Southbound motorists will also have the option of taking the 5 to eastbound state Route 94, then head north on Interstate 15 to northbound Interstate 805, then west on Interstate 8 to northbound state Route 163.
The work is part of a project to replace deteriorated concrete and steel, and to seismically strengthen the 100 year-old bridge, Caltrans officials said. The project is expected top be completed early next year.