County roads in Woodbury dominate a ranking of highways in Washington County that could benefit from safety measures to reduce serious and fatal vehicle crashes, a state-funded safety study says.

Intersections along Radio Drive, Valley Creek Road and Woodbury Drive were identified using a new method of assessing traffic safety, which involves taking preventive action rather than waiting for crashes to occur.

"This is not a list of the most dangerous intersections in Washington County," said County Engineer Wayne Sandberg.

Instead, he said, the study is a "measurement of risk" that allows the county to target spending to most benefit public safety. "We have more information on the risk factors than we ever had before," he said.

Washington County has rebuilt portions of Radio Drive and Valley Creek Road in recent years and currently is widening a stretch Woodbury Drive, a major north-south arterial also known as County Road 19. The roads are among the busiest in the county with posted speed limits of 45 to 55 mph. Numerous intersections have traffic signals.

Statewide crash statistics show most serious injury and fatal crashes occur at signals, said safety engineer Howard Preston. "The most common type of crash at signalized intersections is an angle crash, when someone is running a red light," Preston told county commissioners last week. "It's a serious problem."

All 87 Minnesota counties are writing highway safety plans, with hopes that federal funding will pay for improvements to diminish potential hazards. In Washington County, recommendations would cost $7.9 million if they all were implemented.

The study represents new thinking that prevention is a better strategy than reacting to crashes, said Joe Gustafson, a Washington County transportation engineer who worked on the study. "It creates an image with the public that you're going to wait for something bad to happen before you spend a dime for safety," he said.

Preston, a senior transportation engineer at Ch2M Hill in Mendota Heights, said research shows that severe crashes happen all over the county, not just on sharp curves where many people think they're concentrated. "I can't find a Dead Man's Curve in Minnesota," he said, referring to the common name for high-crash roads.

Most crashes occur at intersections with traffic signals and that calls for strong red light enforcement, he said. But police tell him it's rare when they can put two officers at the front and back of intersections to catch violators.

None of the recommended improvements involve rebuilding roadways. To catch red-light violators, low-cost "confirmation lights" could be mounted at signal intersections to inform a single officer waiting on one side that the light had changed on the other. More "countdown pedestrian timers" at intersections were recommended, as were center turn lanes at some locations, "center buffers" on some roadways at risk for head-on collisions, and other safety devices such as rumble strips, "chevron" signs that warn of sharp curves, and street lighting to improve night visibility.

County Administrator Molly O'Rourke said timing of the study is significant because traffic safety was a top concern among residents in the just-released 2013 quality-of-life survey. The traffic study was presented in a board workshop, where no action was taken.

Gustafson pointed out that Broadway Avenue in Forest Lake, once considered the most dangerous road in Washington County, has been reconstructed to reduce a high number of crashes.

"I'm happy to say that roadway is now very different," he said.