The Highway 99 underpass on 16th Street is currently closed nightly through Sept. 27 for construction, the California Department of Transportation reported.
The underpass is closed from 6 p.m. to 6 a.m. every night while workers remove temporary structures, according to a press release.
Crews also plan to close some ramps on Highway 99 until May next year for work on the roads and bridges. The northbound on-ramp from Highway 140 near 15th Street, southbound on-ramp from G Street and the eastbound connector ramp from Highway 140 near Main Street are all closed.
Drivers should expect five-minute delays, the release stated, and alternate routes are recommended. Construction is subject to change due to weather and other issues, the release stated.
The work is part of the $32.4 million State Route 99 East Merced Overhead Project, which began June 2012. The project will widen the bridges, install a concrete median barrier and upgrade the existing guard rails, among other changes, according to Caltrans.