US uses technology to triage nation's potholed roads

Phoenix, Arizona

THE white Ford van rumbled down Devonshire Street, past the green-trunked palo verde trees and gravelled lawns of central Phoenix. Lasers up front mapped the road's roughness, and high-definition cameras on spider-like arms in the back recorded continuous images of cracked asphalt.

With 65 per cent of US roads rated in less than good condition, cities and states no longer leave funding decisions to intuition and influence. Instead, they use data vacuumed up by arachnid-armed "spider vans" with bulbous cameras and global-positioning equipment protruding from roofs. Six computers inside Phoenix's four-tonne vehicle stored data for engineers to download.