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Good Question: Who Sets The Speed Limits?

MINNEAPOLIS (WCCO) -- Speed limits have been around in Minnesota since 1881. Back then, a streetcar in Duluth couldn't go above 6 mph. It wasn't until 1937 that the state statutes as we know them were written.

That had Dan from Minnetonka asking: Who sets the speed limits?

According to Sue Groth, the state traffic engineer for MnDOT, there are two different ways speed limits are set in Minnesota

The first way is statutory.  The law limits to 10 mph in alleys, 30 mph on urban streets, 55 mph on other roads, 65 mph on expressways and urban interstates, and 70 mph on rural interstates.  Statutory limits are not required to be posted because MnDOT assumes most people already know the limits they should have learned for their drivers' test.

"Sometimes statutory limits don't work for every condition," Groth said.

For example, Hiawatha Avenue can be considered a city expressway.  There, the limit is 40 mph.  In cases like that, the owner of the road – usually the a county or city – will ask MnDOT to do a speed study.  In a speed study, engineers examine the road, pedestrians, crash history and how fast people are already going.  MnDOT then decides if the speed limits should change.

MnDOT estimates it conducts 100-120 speed studies per year.

Some cities have pushed for to change the law to lower city speed limits from 30 mph to 25 mph.  Some in law enforcement say they don't have the resources to enforce that change.  MnDOT says research doesn't show a speed limit change to 25 mph would make people safer.

"You can change a speed limit sign, but that's not necessarily going to change the driver behavior unless you do something else, like having enforcement or actually changing the environment that the person is driving in, by adding parking or making them feel there's a reason to slow down," Groth said.

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