OAKLEY -- Drunken driving arrests have spiked here in the past couple of years, with the city logging up to four times that of its neighbors in 2010.

It's unclear, however, whether the jump indicates that more people are driving under the influence or that police have simply become more adept at catching offenders.

"We have a terrible DUI problem in the city," said Councilman Randy Pope at a City Council meeting earlier this year, where he noted that Oakley police arrested 320 people on suspicion of driving under the influence of alcohol or other drugs during a six-month period from July to December last year.

Annual totals tell the same story: Whereas Oakley logged 157 DUI arrests in 2008, that number jumped to 355 in 2009, an increase of 126 percent. Last year, it rose by 69 percent to 601 arrests.

This year, officers had made 244 DUI arrests as of May 15.

"Traffic safety is a high priority in this city," police Chief Bani Kollo said in an email. "We started a traffic unit several years ago and "... have increased our skills and abilities in traffic enforcement to include DUI enforcement. We have very motivated officers that take their jobs seriously."

Pope, an Oakland police sergeant, wants the city to take additional steps to get impaired drivers off the roads.

He'd like to see retailers that sell alcohol pay a fee that police would use to inform liquor licensees of the law and enforce it through periodic checks. The check might include undercover sting operations to ensure that bars aren't serving alcohol to minors.

City Manager Bryan Montgomery said the city is considering a ballot measure proposing revisions to its business license tax that could incorporate Pope's idea.

The city also has applied for a $48,000 grant to the state Office of Traffic Safety, money that Pope said it would use for overtime pay so that police can conduct DUI checkpoints and otherwise focus on specific areas of the city.

Meanwhile, Oakley police are much busier nabbing motorists on suspicion of DUI than their counterparts elsewhere in East Contra Costa.

Unlike Oakley, these type of arrests declined in Brentwood and Antioch over the past two years. And all three of the region's other cities reported far fewer DUI arrests in 2010 than Oakley; Antioch, a city with about triple Oakley's population, came in a distant second with 240.

Taking population disparities into account, Oakley led the pack with 16.9 DUI arrests per 1,000 residents compared with 2.97 for Brentwood, 2.35 for Antioch and 2.25 for Pittsburg.

Last year's total also was significantly more than all the other DUI arrests made by the Contra Costa Sheriff's Office, which provides police services in the city: 601 for Oakley compared with 407 for the rest of the county.

Councilwoman Pat Anderson and Vice Mayor Kevin Romick believe that having Highway 4 run through town is a contributing factor to the high number of Oakley arrests.

The sheer volume of traffic on Main Street increases the probability that there are intoxicated drivers, Romick said; Anderson thinks it's easier to spot erratic driving on a long, flat stretch of road where vehicles are traveling faster.

"We don't have a lot of bars in town, but we are an in-between spot," she added, noting that nonresidents are being pulled over in Oakley on their way home from drinking holes elsewhere.

And there are a lot of them: Only 24 percent of the 320 arrested during the latter half of 2010 lived in the city, according to police records.

An additional 24 percent were from Antioch, 11 percent from Brentwood and 6 percent from Bethel Island. The remainder was grouped under "other."

Like Kollo, though, Anderson thinks the main reason for all the arrests is the training given some Oakley police officers to spot impaired drivers.

So does Romick.

"Our officers are more aggressive "... because of the ability they have to identify someone under the influence," he said.

Brenda Frachiseur, assistant state executive director of Mothers Against Drunk Driving, agreed, saying police departments that make lots of DUI arrests often have personnel with expertise in this area.

Another explanation is that some officers are simply more focused on stopping drunken drivers than other types of crime, said Sgt. Walter O'Grodnick of the Brentwood Police Department.

Oakley police Officer Lance Morrison was honored in March in a statewide event that MADD held to recognize both individuals and agencies for their efforts to combat the problem. Morrison alone made 251 DUI arrests in 2010, according to the nonprofit group's Sacramento office; he also was commended in 2009 for the 212 arrests he made that year.

The Oakley Chamber of Commerce honored Morrison Friday as the city's police officer of the year.

Time and money are other variables that can affect the number of DUI arrests in a particular city.

The more calls for service that police receive, the less time they have to concentrate on bad drivers, O'Grodnick said.

Oakley's relatively low overall crime rate is why bar and restaurant owner Mike Fagan thinks police have the time to park near his business on Thursday nights, when Mike's Beef 'N' Brew sells $1 beers until closing.

Their presence dissuades some would-be patrons from coming in, he said, adding that he and his employees give rides home to those who overindulge and don't want to wait for a taxi.

Fagan said he also warns patrons that they probably will get caught if they drink and drive.

Even so, he acknowledges that some of his tipsy customers probably are among the statistics.

How much attention a police department can devote to one type of crime depends on the amount of money at its disposal.

Law enforcement agencies can't all afford to have officers dedicated to enforcing traffic laws. Oakley's police department budget has grown steadily over the past four years, and the city hasn't eliminated any officer jobs since it incorporated in 1999.

The 28-officer department now includes a two-person traffic unit, whereas the Antioch Police Department last year disbanded the one it had and transferred those positions to its patrol bureau, where police respond to all calls for service.

A disparity in arrests also could mean that a city with fewer of them already has gotten a handle on the problem, said Pittsburg police Capt. Brian Addington.

His agency has a five-person traffic division, but Addington thinks the reason Pittsburg's DUI numbers aren't higher is in large part because of its relationship with the East County Alcohol Policy Coalition, which works with law enforcement and alcohol vendors to prevent underage drinking.

His officers' involvement in the group helps remind them to look for drunken drivers, he said.

Whatever the reasons for its arrest count, Oakley is tackling DUIs on multiple fronts.

An ordinance the council adopted in January allows the city to bill the responsible party for the costs of responding to and following up on accidents caused by impaired drivers. Over the past decade, DUI accidents in the city have killed nine people and injured 54 others, according to California Highway Patrol records.

Although Pope credits the city's tough stance with reducing the number of collisions, "we still have room to improve," he wrote. "I believe that DUIs are 100 percent preventable."

Rowena Coetsee covers Oakley. Reach her at 925-779-7141.