The Arizona Department of Transportation (ADOT) is getting into the recycling game and saving the state money by reusing what normally would be sent to the dumpster.
As part of a widening project that will make 1-10 a six-lane freeway from Casa Grande to Tucson, materials removed from the old westbound lanes are being put to good use, serving as a foundation for new lanes.
ADOT spokesman Tom Herrmann says about 1 million square feet of asphalt is being removed from a 4-mile stretch of freeway, and new travel lanes are being built about 100 yards from the existing ones. As the lanes are torn out, the asphalt is ground and then laid down as the base for the new lanes without having to bring in fill dirt.
“Usually, we have to haul material in from some off-site location, which can be expensive,” says Dave Locher, ADOT’s regional engineer and project manager. “But in this case, the better answer was literally right in front of us.”
Often with large projects, crews have a “borrow pit” for when they need additional dirt. “It’s usually located near the project in a site where moving earth doesn’t create additional environmental or economic concerns,” Herrmann says. “Hauling that extra dirt adds time and money to the project.”
In addition to the asphalt recycling, ADOT will take the old guardrails that are in good condition and reuse them in repair projects around Arizona.
“The savings for us is considerable in both time and money,” Herrmann says. “Among the many recycling programs around Arizona, not one includes old freeways as a recyclable item. By putting old I-10 to use in building new I-10 in Pinal County, we’re doing our part.”
Construction of a dust-detection system will begin in spring and run from mile post 209 to 219. It will include electronic variable speed-limit signs used to warn drivers to slow down during a dust storm. The entire project should be complete by early fall.