Southern Maryland roadways were among the most dangerous in the Washington region last year, according to recently released statistics.

St. Mary's, Calvert and Charles counties ranked in the top six among 19 jurisdictions in the region for the rate of fatalities among licensed drivers, according to data kept by the Maryland State Highway Administration, the Virginia Department of Motor Vehicles and the District Department of Transportation.

Those agencies also reported that drunken driving was to blame for about half or more of traffic fatalities last year in St. Mary's County and three other jurisdictions: the District, Fairfax County and Fairfax City.

The new figures came on Labor Day weekend, which traffic experts projected would be one of the busiest travel periods in nearly a decade. The holiday also traditionally records among the highest numbers of alcohol-related fatalities, prompting law enforcement agencies around the region to ramp up drunken driving checkpoints.

About 45,000 people die each year on the nation's highways, and alcohol plays a role in about a third of that toll, said Lt. Homer Rich of the Maryland State Police in Prince Frederick. "If we can reduce the number of people drinking and driving on our highways, we can also probably reduce the number of people dying on our highways."

St. Mary's County had the second highest fatality rate in the region with 1.27 deaths per 10,000 licensed drivers. Only Fairfax City had a higher rate, 1.54 deaths, according to the Virginia Department of Motor Vehicles, which keeps data on all Virginia jurisdictions.

Calvert County was fourth, with 0.84 deaths per 10,000 licensed drivers, and Charles County was sixth with 0.64 deaths, according to the State Highway Administration, which disseminates data on counties but not cities.

Alcohol-related fatalities rose from 2002 to last year in Maryland and the District and declined in Virginia, according to the National Highway Traffic Safety Administration.

The federal agency is in the third year of its Checkpoint Strikeforce initiative, an enforcement and public education campaign aimed at getting impaired drivers off the road. Under the program, there is at least one sobriety checkpoint each week in every mid-Atlantic state from July 4 to Jan. 4. The region includes the District of Columbia, Virginia, Maryland, Delaware, Pennsylvania and West Virginia.

Last year, the program resulted in 23,665 citations that included 2,300 DUI arrests, according to the agency, which organized the nationwide "You Drink & Drive. You Lose." crackdown that stretches over a 16-day Labor Day period ending Sept. 11.

Kurt Erickson, president of the Washington Regional Alcohol Program, said that nearly 16,000 people were arrested on DUI charges in 2002 in the region. "The checkpoints do work," he said.

The traffic safety administration recorded 42,643 traffic fatalities last year, down from 43,005 the year before. The agency said 17,013 of the deaths last year were alcohol-related, a decrease of about 3 percent from 2002.

Last year in Maryland, 281 of 649 traffic deaths were alcohol-related. In the Washington region, St. Mary's County had the second-highest rate of alcohol-related fatalities -- 50 percent -- with eight of the 16 traffic deaths blamed on drunk drivers.

The county's rural countryside is mostly to blame, said St. Mary's Sheriff David D. Zylak. "Crashes are more severe" on rural roads where speeds are greater, he said. He also said that low staffing in his department may play a role, with fewer patrol cars deployed.