KENT COUNTY, Mich. — A new study shows the numbers of crashes and deaths on certain highways across Michigan rose in the years after state lawmakers increased speed limits.
According to the research, the total number of crashes increased 16.7%, from an average of 3,634 per year to 4,241.
The number of deaths and serious injuries went from about 64 to 80 per year, a 25% increase.
In 2017, the legislature approved a series of bills, which allowed 75 mph speed limits on over 600 miles of rural freeways.
It includes a section of US-131 in Kent and Montcalm counties.
“There's [a] push [for this] because basically people want to get from point A to point B as quickly as possible, and there are economic factors like freight, shipping, trucking and so forth, but with those lower travel times, there are costs and one of those is increases in crashes, injuries and fatalities,” said Professor Peter Savolainen, who conducted the analysis.
Savolainen is a professor at Michigan State University who specializes in traffic safety.
He says his team examined data from Michigan State Police in the three years before the speed limit increase and the two years after it.
“There’s at least two different things happening,” said Savolainen. “I think one of which we've got more variability in speed, so you've got a group of faster drivers and a group of slower drivers and anytime you have that there's an opportunity for crashes. Then when crashes do occur, if the vehicles are going faster, there's more likely to be serious injuries just based on physics.”
Savolainen acknowledges traffic volume increased during the time periods, which likely contributed to the rise, but he calls the numbers statistically significant and in line with past results.
“In 1987, they [the U.S. government] basically allowed states to raise limits to 65 miles per hour on rural interstates and fatalities went up,” said Savolainen. “Then in 1995, they said states can basically do whatever they'd like and that's when you see states like Montana basically had no practical speed limit on some of the roads and fatality numbers have continued to climb.”
Despite the trends, Savolainen says it’s unlikely for speeds to go back down.
More enforcement may help, but he notes a lack of funding for those efforts in most police departments across the state.
In the meantime, he encourages people to take on the challenge themselves and make smart decisions when behind the wheel.
“I think we should probably be cautious about where we show future increases,” said Savolainen. “If we look at the sites where the increases have gone into effect here in Michigan, those were the best sites because they pick sites that historically had fewer crashes, sites that had better characteristics, so wider lanes, wider shoulders that could accommodate that, and so, they basically, for lack of a better term, they pick the the safest 600 miles. If we were to see further increases, we'd be moving to sites that aren't as inherently safe and so I'm worried the numbers would be even worse in that case.”
To read the full study, click here.
