Y2: Oral Presentation C Friday, 11:00 � 11:30 am C Lake Superior Ballroom O

State Wide Snow Trap Inventory

Dan Gullickson
Minnesota Department of Transportation
MS 620
395 John Ireland Boulevard
St. Paul, MN  55155

Dan Flatgard, Steve Kortuem
Minnesota Department of Transportation
501 South Victory Drive
PO Box 4039
Mankato, MN  56001

Description: This project identifies the snow trap sites along State roads. Snow trap sites are defined as sections of roadways that:

  1. drift shut and are impassable

  2. have a snow drift that shuts down a lane of travel

  3. have slush or �blow ice� build up on the road

  4. experience poor visibility �white out� conditions

The data is collected in the field using a Trimble Pro XR GPS unit that has sub-meter accuracy. One person from Mn/DOT maintenance drives the vehicle and provides insight on what it is like to plow snow along the problem section of highway. A second person rides along and uses the GPS equipment to collect site data and to record the locations of the snow trap.

After collecting the site data, the data is downloaded into Trimble�s Pathfinder Office program for export into either a Microstation or an ArcView format.

In ArcView the layers of data can be analyzed and mapped. The crash severity- (fatal injury, incapacitating injury, non-incapacitating, possible injury, property damage) can be analyzed within the snow drift area. The severity of the drift problem, such as the drift- (closes road, extends to centerline, or extends only to the edge of drive lane) is compared with the extra equipment required to keep the road open. This allows one to see where the money is being spent to keep the highway open and the potential economic impact to commerce of having closed roads.

This inventory aids the decision making process of what type of treatment (earthwork, living snow fences, structural snow fences) best solves the blowing and drifting snow problem based on social, economic and environmental reasons.