San Francisco police are among those paying extra attention to motorists who might be driving under the influence over the holiday weekend.

A Friday, July 1, sobriety checkpoint aimed at drivers on their way to the Golden Gate Bridge and saturation of the freeways by two area commands of the California Highway Patrol are scheduled for the four-day Independence Day weekend as Avoid the 14 cracks down on intoxicated drivers in San Francisco.

The 14-agency cooperative effort starts its crackdown on Friday, July 1, and ends at midnight on Monday, July 4.

Sheriff's deputies and officers from the Amtrak Police and United States Park Police will join traffic officers from the San Francisco Police Department.

“Monday’s fireworks are bound to cause traffic congestion and rubbernecking. Alcohol makes it worse, because impaired drivers can't react fast enough to hit their brakes before crashing into a car that's stopped to watch the display,” he said. “Designated drivers, those who stay sober and drive everyone else home, will help the situation.”

San Francisco and Marin area commands of the CHP will be at maximum enforcement levels all weekend, said Lt. Gene Choi of the San Francisco office, fielding 75 to 90 percent of available officers. The Marin CHP office is responsible for patrolling the Golden Gate Bridge.

Officers made 54 DUI arrests in San Francisco during last year's Independence Day weekend. DUI suspects killed or injured no one. The arrest figure is nearly double the previous year.

The four-day weekend surrounding Labor Day will also see Avoid the 14 DUI blitzes, as will the winter holiday period at the end of the year, Corrales said.

Avoid the 14 is part of a nine-county Bay Area Avoid Campaign. Similar campaigns are in effect in Santa Cruz and Monterey Counties and in 10 other counties in California. The state Office of Traffic Safety funds them through the Business, Transportation, and Housing Agency.