Pavement management software can predict when a street will reach the critical point where it will deteriorate quickly and need reconstruction. That's important, because Oxnard figures reconstruction costs about $7.20 per square foot versus resurfacing at $1.30 to $2.90 per square foot.
“The tricky part is to let it deteriorate to just before it requires reconstruction,” Rydberg says. “If you fix it too soon, you've repaired it while it still had useful life. But if you wait too long, it'll require significantly more expensive repair or reconstruction.”
For example, in 2000 one of Oxnard's main east-west arterials, Gonzales Road, was nearing the end of its life. Its condition index had dropped from 69 in 2000 to 57 in 2003.
The division couldn't resurface the street because the city planned to place a major sewer trunk there the next year. So it did some patching, reducing the decline in the condition index to only 2 points from the 6- to-8-point drop that would have occurred without the stopgap maintenance.
Rydberg uses the condition index to prioritize funding by neighborhood. “We design projects block by block to develop the most cost-effective maintenance plan,” he says. “We just finished a neighborhood where half the streets got a slurry seal and half received an overlay.”
Each November, just before the rainy season, Oxnard inspects all arterial streets and one-third of its residential streets. The division has retained Pavement Engineering to conduct the survey for a number of years; this year, the assessment cost $35,000 for 190 miles.
MicroPaver customers include the U.S. Air Force, the U.S. Army, the Federal Aviation Administration, and the Federal Highway Administration.
Non-Defense Department sales and support services are provided by the American Public Works Association and the University of Illinois Technical Assistance Center in Urbana-Champaign, Ill. Subscriptions from the University of Illinois are $995 for the first year; renewals are $950 per year. Last year, the university sold 43 new subscriptions.
For more information visit www.apwa.net or www.tac.uiuc.edu., and read the article Paving for the Long Haul
— Daniel C. Brown is a freelance writer based in Des Plaines, Ill.