Thirty-eight percent of the main city and county streets and state highways are in poor condition, according to the Michigan Transportation Asset Management Council - a significant jump from last year's 33 percent.
The Council sends out 100 teams of drivers every year to assess the condition of Michigan roads.
Road conditions have been declining for the nine years the Council has done the study - but the decline between 2013 and 2014 was particularly steep, says Council Chairman Roger Safford.
Costs to repair the roads go up - but revenues are declining. So road crews are playing a game of one step forward, two steps back.
"They've been using preventative maintenance strategies to minimize the decline," Safford says. "But they're fighting a losing battle against the traffic and weather and just the natural aging of the system. And at current funding levels, the system will continue to decline."
Safford says his group does not take a position on the complex ballot proposal going before voters in May, which would, in part, increase road funding.
But he says there's nothing very surprising about what is happening in Michigan.
Take Ohio, just a bit south of us, where winters are often just as harsh.
Visitors from Ohio tend to be shocked, Safford finds, at the condition of Michigan roads.
"The main reason for that is because they invest about a billion dollars more per year in their road system."
You can read a post by Michigan Radio's Mark Brush explaining the May ballot proposal here.