Feature Story

Better Roads Staff

That is the other reality of today’s sophisticated pavement management systems: while they stretch the tax dollar further than ever before, if the state or city or county fails to provide sufficient funds, the management system can’t save pavements — it can only chronicle the demise.

With Nevada experiencing extraordinary population growth, the DOT’s budget priority was expanding system capacity with new construction, while maintenance for 13,000 miles of existing pavement was given a lower priority. As a result, the state was spending too little on maintenance and too much on expensive rehabilitation and rebuilding.

Bemanian, now a pavement design and lifecycle cost specialist at Parsons Transportation Group, wanted to create a system for managing Nevada’s highway assets the way a business manager like Warren Buffett would. She and NDOT Materials Division staff ended up with a system very similar to the one Hillsborough County would develop years later. NDOT’s Materials Division staff developed a database that included the inventory of the entire system and established basic performance models for each highway classification and treatment.

The performance models show that a timely intervention is cheaper than waiting to act until a pavement descends into rebuild condition.

In a paper published in a 2005 edition of Transportation Research Record: Journal of the Transportation Research Board, Bemanian et. al. wrote, “The rehabilitation cost for a 10-mile section of Interstate will cost $4 million at the optimum time for treatment versus $10 million at the failure point (2 to 3 years between optimum and failure points) for a cost difference of $6 million.”

Substantiated by NDOT’s own data, this and many other examples of the economic importance of timely preventive maintenance convinced the DOT to give budget priority to maintenance, and to the concept of managing the system proactively rather than reactively.

System management for NDOT means prioritizing the heaviest used roads in times of financial duress, just like it does for Hillsborough County and any other sophisticated pavement management agency. Again, Bemanian’s cost metrics:

“The rehabilitation cost for a 10-mile section on a lower-volume road is $1.3 million at the optimum time and $2.5 million at the failure point (4 to 6 years between optimum and failure points) for a cost difference of $1.2 million. Therefore, the Interstate project has the highest financial consequences if work is not performed earlier rather than later.”

This strategy is being widely applied across the country. In Illinois, IDOT’s Division 1 encompasses the greater Chicago metropolitan area and some of the country’s heaviest travelled Interstates. Program development manager John Fortmann told Better Roads that the Division has always had enough state funds to get their full federal match, and that they strive to keep 90 percent of their Interstate pavement in good/excellent condition by putting most of the budget in prevention.

Division 1 has been helped by the state’s multi-year road/bridge program, a recent investment that followed several years of state-wide underinvestment in roads and bridges.

While Division 1 has enjoyed funding priority to avoid the negative consequences of late intervention on such heavily travelled roads, there has been limited funding for other system needs, such as capacity expansion, modernization, or rebuilding the roadway system.

That is the other reality of today’s sophisticated pavement management systems: while they stretch the tax dollar further than ever before, if the state or city or county fails to provide sufficient funds, the management system can’t save pavements – it can only chronicle the demise.

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