SAN DIEGO – If you are planning to celebrate St. Patrick’s Day with green beer or Irish whiskey, be sure you take public transportation or have a designated driver.

San Diego County law agencies are warning drivers that they will set up DUI checkpoints around the county Friday night in an effort to prevent accidents caused by drunken drivers.

The San Diego County Sheriff’s department said it plans to increase DUI patrols in its jurisdictions starting at 6 p.m. Friday and continuing until at least 3 a.m. Saturday. The department will also set up a checkpoint somewhere in Encinitas.

The San Diego Police Department will set up a DUI checkpoint to screen all passing drivers between 11 p.m. Friday and 3 a.m. The department did not say where the checkpoint will be set up, but it said the location is usually chosen based on the frequency of past DUI and crash statistics.

El Cajon police also announced they will have increased patrols and DUI checkpoints operating from 5 p.m. Friday until 1 a.m. Saturday.