Here's a notice via the California Highway Patrol:

A Sobriety Checkpoint will be conducted on Sunday, September 25, by the California Highway Patrol’s Dublin Office. The checkpoint will take place near the City of Livermore from approximately 2p.m. to 10p.m.

Motorists approaching a checkpoint will see informational signs advising them that a sobriety checkpoint is ahead. Once in the checkpoint lane, motorists will be delayed only a few moments while an officer explains the purpose of the checkpoint.

A key objective of the checkpoint is to reduce the number of drinking drivers on the road, rather than produce dramatic increases in DUI arrests. Roadways with established DUI problems are targeted for checkpoints.

This check point is just one of the traffic safety programs funded by grants secured by the California Highway Patrol (CHP) from the Office of Traffic Safety.