SAN DIEGO (CNS) - Northbound Interstate 805 is scheduled to be closed Wednesday and early Thursday from La Jolla Village Drive to the I-5/I-805 merge as Caltrans crews pour concrete ahead of adding a carpool lane.

The closure will be from 9:30 p.m. today to 5 a.m. Thursday, if weather permits, according to Caltrans.

Most northbound traffic will be detoured onto westbound state Route 52 then onto northbound Interstate 5 back to the 805. Motorists will be allowed off at Governor and Nobel drives, the state transit agency reported.

Caltrans officials said the closure is necessary so crews can continue working on the roughly $86 million first stage of the I-805 North Express Lanes Project. In addition to adding carpool lanes that will eventually extend in both directions from state Route 52 to Mira Mesa Boulevard, plans for the project include constructing a direct access ramp at Carrol Canyon Road.