The largest summer mobilization ever is cruising King County roadways through Sept. 6 for the state's "Drive Hammered, Get Nailed" campaign against drunk driving.

Burien, Des Moines, Normandy Park, SeaTac, Tukwila and Port of Seattle police will join the Washington State Patrol and other agencies on extra DUI patrols along county roadways in search of impaired drivers.

This Drive Hammered, Get Nailed will be the largest summer DUI enforcement campaign ever with 178 agencies participating throughout the state.

During the summer months - July through September - Washington experiences the greatest number of alcohol or drug impaired driver-involved traffic deaths, according to law enforcement officials.

Labor Day weekend is one of Washington's deadliest holidays, averaging more than seven deaths each year. Impaired driving is the leading factor in traffic deaths in Washington.

Last year, impaired drivers contributed to the deaths of more than half of the 491 people who died on Washington's roadways, the offcials said. The 264 impaired driver-involved deaths in 2009 represent a decrease of nine fatalities compared to the previous five-year average of 273.

"Every life lost at the hands of an impaired driver is preventable which makes each tragic death even more painful to the families and friends who suffer the loss of a loved one," said Lowell Porter, director of the Washington Traffic Safety Commission.

Although this emphasis patrol is occurring during the summer, law enforcement statewide conducts extra DUI enforcement throughout the year.