WALNUT CREEK, Calif. (KTVU) -- It was that greenest of holidays, when everything, even the beer, changes color. On Tuesday, people around the Bay Area celebrated St. Patrick's Day.
But while the party was underway, so was the police crackdown.
In Walnut Creek, the festivities started around lunchtime.
"St. Patrick's Day is a big deal for me," said Ed Duarte of Pleasanton.
"A celebration of all thing Irish," added Kent Brewer of Orinda.
The holiday is typically a big night for bar business and for people who want to party.
"It means nothing in particular to me except for the fact that it's a day for good beer, and friends and wearing green, and getting out there in the Creek," said Kyle Taylor of Clayton.
But it's never a good time for anyone who chooses to drink heavily and get behind the wheel. Walnut Creek Police brought in reinforcements to help keep the roads safe on the holiday.
"Really, any violations. They could be weaving, they could be red light runners, they could be speeding. Any of the normal violations. And they're just more likely to occur if you've been drinking," said San Ramon Police Sgt. Pat Cerruti.
Officers from Martinez and San Ramon are here as part of a three city partnership, in which each city gets saturated with enforcement once a month.
"We're out there as a regional traffic unit. And we're doing high-profile enforcement," added Cerruti.
Every weekend, Walnut Creek sees about eight DUI arrests. And that doubles when St. Patrick's Day falls on a Friday or Saturday. Officers are pleased that this year the holiday is on a Tuesday.
"Go out, use it for an excuse to have a good time, but be responsible. Don't drink and drive, it's never ok to do that," advised Walnut Creek Police Lieutenant Bryan Hill.
Inside Stadium Pub on Main Street, the staff also tries to ensure customers stay safe.
"As soon as somebody starts getting kind of a little too much, it's like, 'OK, how about some water?' And if they don't want that, it's like, 'I'm sorry, I can't serve you anymore, '" explained waitress Jillian Jones.
As of 5 p.m., the party had yet to really get going, but everyone expected a very busy night.