Antioch and Pittsburg drivers beware: the state will alternately shut down and reopen all eastbound and then westbound lanes of State Route 4 between Somersville Road to Loveridge Road for late night work beginning Thursday.

The shutdowns are part of the ongoing effort to widen that stretch of the highway and will see the full opening of a new, permanent eastbound off ramp at Somersville Road, as well as shifting westbound traffic to run a portion of the newly constructed Century Boulevard Bridge.

The SR-4 eastbound shutdown will take place from Loveridge Road to Somersville Road between 10 p.m. and 5 a.m. Thursday night and Friday morning. All lanes of Somersville Road at SR-4 will be closed between midnight and 5 a.m. Friday morning.

The westbound shutdowns will close that stretch of SR-4 from Somersville Road to Loveridge Road on Wednesday and Thursday nights between 10 p.m. and 3:30 a.m., and on Friday night between 11 p.m. and 5 a.m. The westbound on-ramp from Somersville Road will also be closed between 10 p.m. and 5 a.m. on Wednesday and Thursday nights and between 11 p.m. and 6 a.m. on Friday/Saturday.

For more information, visit the project's website at http://widensr4.org.

Contact Sean Maher at 925-779-7189. Follow him on Twitter at @OneSeanMaher.