For businesses looking to relocate or residents pining for a Sunday drive, Indiana drivers will find open roads with nary a pothole in sight. According to CNBC’s yearly tab of “America’s Top States for Business,” Indiana regularly nabs first place for its well-maintained infrastructure. 

But accolades and acclaim may soon sour if the Hoosier State invites larger, heavier trucks onto its roads. Even though heftier vehicles have been linked to hundreds of millions of dollars in increased taxpayer costs, a joint committee of state legislators are considering recommending higher weight limits across the state. This misguided policy would drive bills higher from South Bend to Evansville, leading to a pileup of repair work and dashed expectations.

Currently, Indiana gets the best roads in the country for a bargain. According to data from the National Association of State Budget Officers, Indiana spent a paltry $2.2 billion on transportation expenses in fiscal year 2017. Compared to somewhat near-neighbor Wisconsin, which has a smaller population than Indiana, Wisconsin yet still manages to spend $500 million more per year on maintaining its infrastructure. Also, Indiana has 1 million more residents than Minnesota, yet still manages to spend $1 billion less than the land of 10,000 lakes. 

Indiana may soon be on the losing side of these comparisons, though, if a vocal minority of state lawmakers get their way. A growing chorus of policymakers and talking heads are pushing for the state to revisit its current weight limits on trucks. Currently, Indiana allows trucks on its roads weighing up to 80,000, which matches federal regulations. Following a recommendation from a joint committee of state lawmakers, this weight limit may skyrocket to more than 160,000 pounds. At that point, Indiana would need an exemption from current federal standards on roadworthiness.

But even if Indiana can get the federal government’s blessing, it would be unwise to allow heavier trucks. To see why, Hoosiers needn’t look further than their northern neighbor, Michigan. The state currently has the highest allowable truck weights in the country, and the beleaguered state has paid dearly for the privilege. Lv15, which creates HD maps for self-driving cars, examined the roads of different states using more than 15 million pictures taken by iPhone dash cam apps determined that Michigan has some the nation’s worst roads. The study was able to rule out regional factors, such as rough winters, being behind Michigan’s malaise. States such as Indiana, Ohio, and Iowa have rough winters on par with Michigan's, yet their roads are in far better shape. Lv15’s analysis also ruled out factors such as state construction and gasoline tax rates as culprits.

Attributing blame for infrastructural issues is hardly a science. But the science is clear about the impact of vehicle weight on road quality. Judith Corley-Lay, the chief pavement management engineer for the North Carolina Department of Transportation, studied the issue at the request of state lawmakers over a decade ago and found overweight trucks cost her state $78 million per year in added taxpayer costs. Corley-Lay states the obvious: “If you have to treat a road in five years instead of eight, or in eight years instead of 12, there’s a real cost impact.” The Government Accountability Office similarly confirmed that gravity works, finding more than twenty years ago that the road damage caused by one 18-wheeler is equivalent to 9,600 cars.

Decades of evidence backs up what road engineers have long known: heavy trucks wreak more than their fair share of havoc on roads. If Indiana goes the way of Michigan, taxpayers would have to shell out tens of millions of dollars for roads suddenly riddled with potholes. The state lies at the crossroads of sensible and disastrous transportation policy. With continued, common-sense weight limits on trucks, Indiana can keep up the cruise control on its first-in-the-nation infrastructure system.   

Ross Marchand is the director of policy for the Taxpayers Protection Alliance.