Federal Highway Administration > Publications > Focus > September 1997 >
Preventive Maintenance Yields Huge Savings, Says Michigan Study
September 1997Publication Number: FHWA-SA-97-027
Preventive Maintenance Yields Huge Savings, Says Michigan Study Maintenance engineers have been making the case for preventive maintenance for years-but their message has often gone unheeded. Now, a study from the Michigan Department of Transportation (DOT) provides hard evidence that preventive maintenance is a wise investment. According to the study, the DOT's preventive maintenance strategy is more than six times as cost-effective as rehabilitation and reconstruction projects.
Michigan DOT adopted its preventive maintenance strategy in 1992 as a way to keep its 15,420 km (9,580 mi) of highways in the best shape possible despite declining financial resources. Since then, preventive maintenance treatments have been applied to about 4,260 km (2,650 mi) of asphalt and portland cement concrete pavements, at a cost of $80 million.
Had the DOT not implemented its preventive maintenance strategy, the study found, the DOT would have to spend $700 million today on rehabilitation and reconstruction projects to bring pavements up to their current condition. That's more than eight times as much money as has been spent on preventive maintenance treatments.
The study was conducted by Michigan DOT's Bureau of Transportation Planning and is based on very conservative assumptions about the performance of preventive maintenance treatments. To further validate the value of preventive maintenance, Michigan DOT hired an independent consultant to verify that the pavements had actually benefited from the preventive maintenance treatments. "We wanted to see whether the treatments had worked and whether they were in fact a good value," says Larry Galehouse, pavement maintenance engineer at Michigan DOT. The consultant concluded that most preventive maintenance treatments were successful in extending the life of the pavement.
Michigan DOT makes the most of its resources by carefully timing the application of preventive maintenance treatments. Galehouse says the DOT has found that applying maintenance treatments to pavements with light to moderate distress provides a substantial improvement in pavement life; in contrast, treating a severely distressed pavement accomplishes very little.
Michigan DOT relies on a wide variety of maintenance treatments, which allows the highway agency to select the least expensive treatment that will address the problems found on a specific pavement. "We don't need an expensive fix for every road," Galehouse says.
The highway agency's preventive maintenance strategy is also designed to make yearly funding needs more predictable. The DOT classifies pavements in one of six categories, ranging from roads in need of almost immediate rehabilitation to roads expected to last for another 2 or 3 decades. Today, the amount of roads in each category varies widely. By carefully matching pavements with appropriate preventive maintenance treatments, the DOT is evening out the disparity; this will prevent huge surges in the number of pavements in need of costly rehabilitation or reconstruction in any given year.
For more information on the Michigan DOT study, contact Larry Galehouse at Michigan DOT (phone: 517-322-3315; fax: 517-322-2699; email: email@example.com).