DETROIT – Residents who think Michigan roads look bad might have nightmares about what lies underneath those roads.

For all the ways its used -- at dinner or when the furnace clicks on -- it's easy to take natural gas for granted. But a study revealed that many of Michigan's natural gas lines are in bad shape.

So how big is the problem, and what's being done about it?

The Midwest is a big place with several older cities, such as Cleveland, Chicago, Indianapolis and Detroit.

But according to a new study, half of the bad gas lines in the central states are in Michigan.

In the past, leaking gas lines have exploded and leveled businesses and houses, leaving everyone sniffing the air and wondering whether whether the fire was caused by gas lines.

An infrastructure reported completed last fall said that "many miles of Michigan pipeline infrastructure that transports natural gas are outdated or have surpassed their useful lifespan, making them one of the state's most pressing issues."

The federal Pipeline and Hazardous Materials Safety Administration "has identified roughly 5,688 miles of at-risk natural gas pipeline in Michigan ... approximately 50 percent of all the at-risk pipe in the PHMSA's 11-state central region."

The findings are why residents can expect to see crews in their neighborhoods soon, according to Consumers Energy.

"Replacing 18,000 vintage gas services that lead to businesses and homes, at least 107 of main, but it is a process, as you can understand," Debra Dodd said.

It could cost around $500 million for the project. and the report said that's part of the problem. State law requires projects to exceed a half-billion dollars, slowing the process down.

Consumers and DTE have both ramped up their programs recently, knowing there's really no choice.

"We're going to be inspecting over 100 miles of main, both direct inspection where we dig up the main and we use some specialized equipment that will travel through the main and look for anomalies we need to repair," Dodd said.

DTE said Wednesday that its new investment is in pipelines in Grosse Pointe, Harper Woods and Dearborn. They need to replace not only bad mains, but the smaller pipes off the mains to homes and businesses.