ALAMEDA COUNTY -- Law enforcement officers will be out in force, cracking down on drunken drivers from now through Labor Day.

Police, sheriff's deputies and California Highway Patrol officers are joining together in the Avoid the 21 campaign, conducting saturation patrols, a warrant/probation and four checkpoints throughout the county as part of a national "Drive Sober or Get Pulled Over" program.

The checkpoints will be Thursday in the city of Alameda; Aug. 25 in Fremont; Aug. 30 in Union City; and Aug. 31 in Hayward.

"Driving drunk is simply not worth the risk, so don't take the chance. Remember, we will be out in force," said Hayward police Chad Sgt. Olthoff, program coordinator.