When the snow falls, plows are dispatched to help keep motorists moving.
Drive reader Dan said he is appreciative of plow drivers' efforts, but he wondered if they have to follow traffic rules when clearing snow.
He was behind two snowplows while heading west on 85th Avenue in Brooklyn Park during a late December snowfall. When the plows — one in each lane — arrived at Zachary Lane, they stopped for a red light. But since there were no vehicles on Zachary Lane, the plow drivers proceeded through the intersection against a red light.
"Is it legal for a snowplow to do that?" Dan asked in an e-mail. "Can plows blow red lights?"
The Drive took the question to the Hennepin County Transportation Department, since the offending plows were county vehicles. The Drive also posed the question to the Minnesota Department of Transportation, which has the largest fleet in the state with more than 800 plows.
"Our crews driving plows should not be traveling through red lights," said Colin Cox, a Hennepin County spokesman. "It is both against county policy and state law."
Under state law, emergency vehicles are permitted to ignore red lights and stop signs while en route to a call. Drivers of emergency vehicles "shall slow down as necessary for safety" and cautiously go through an intersection — with siren activated and red lights displayed — when facing a red light or stop sign.
Most plows in Minnesota have white, blue or amber flashing lights activated when clearing snow.
Minnesota state law defines emergency vehicles as police cars, fire trucks, ambulances, volunteer rescue squads and designated vehicles found by the commissioner of the Department of Public Safety as "necessary for preservation of life or property or to the execution of emergency governmental functions."
Under those parameters, snowplows in Minnesota are not considered emergency vehicles, said MnDOT spokeswoman Anne Meyer.
"Snowplows should follow all traffic laws," she said.
In the same vein, drivers need to respect plows, give them room and understand there is a lot going on in the cab.
"Plow drivers pay attention to the roads, but they also have blades to put up and down and sand and salt to keep track of," Meyer said. "They have a lot to do behind the wheel."
Plows often are traveling below the speed limit because it is more effective in cleaning roads. While there is no law prohibiting antsy drivers from passing a plow, it can be dangerous. MnDOT plows on average are involved in about 100 crashes every season.
Most crashes involving plows happen when drivers try to pass them. Plows have blades that stick out up to 10 feet that drivers may not anticipate. Plows also kick up "snow clouds" that reduce visibility and can cause motorists to lose control and strike the plow, Meyer said.
A fully equipped truck can weigh as much as 66,000 pounds, which is 15 times more than an average car. With that disparity, a motorist colliding with a plow "is not going to win out on that deal," Meyer said.
MnDOT's motto is "Stay Back, Stay Alive," meaning the rules for drivers are to turn on headlights, click off cruise control and keep at least 10 car lengths between their vehicle and a plow.
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