ANTIOCH -- Motorists trying to cut across town this weekend will have one less option, as work continues widening Highway 4.

All lanes of Contra Loma Boulevard will be closed from 11:59 p.m. Friday night to 5 a.m. Monday morning where it crosses under the freeway as the contractor for the project to widen the freeway from four to eight lanes will be installing a new drainage structure, according to a Caltrans news release.

Northbound motorists will be detoured right on Fitzuren Road and north on G Street to 18th Street. Southbound drivers will be directed right onto Highway 4 to the Somersville Road exit, and to Buchanan Road to get back to Contra Loma.

Motorists are advised to expect delays and allow extra time for their commute.

For more information about the Highway 4 widening and road closures, visit http://widensr4.org.

Contact Paul Burgarino at 925-779-7164. Follow him at Twitter.com/paulburgarino.