A long-term project to replace an underground pipe has closed one of three northbound lanes until spring 2024, the California Department of Transportation, or Caltrans, said last Friday, the first day of the closure.

The effort will impact a half-mile stretch south of California Street. The left lane will be closed. Northbound motorists will use the two right lanes.

The closure will run 24 hours a day, seven days a week, as weather and other conditions allow, said Jim Medina, a spokesman for the agency.

The pipe replacement is meant to remedy the perpetually wet spot along the center median that sometimes seeps into the left traffic lane. Workers will dig up pavement to reach the clogged or broken pipe.