Fremont police plan a sobriety checkpoint for Friday, May 25.
The four-day Avoid the 21 crackdown begins at 12:01 a.m. Friday and ends at midnight Monday, said Lt. Ava Garavatti of the Livermore police, campaign chairwoman.
California Highway Patrol officers from the Dublin, Castro Valley, Hayward and Oakland area squads will flood the freeways all weekend.
"The long Memorial Day weekend is the kick-off for summer," Garavatti said. "Have fun at your parties and gatherings, but remember that there is no safe way to drive after you've been drinking alcohol or taking drugs."
"Even a little of either can make you an unsafe driver and subject to arrest," she added. "Designated sober drivers regularly save the day by getting everyone home safely after the event."
Avoid the 21 will hit the roads again around Independence Day, and plans a three-week effort from the middle of August to early September. The California Office of Traffic Safety funds the campaign through the National Highway Traffic Safety Administration.