If you ride through Downtown Knoxville, you might have noticed some new asphalt covering Summit Hill Drive. That's actually a demonstration city engineers are running to determine if it will go in a new direction for future paving projects.
The experiment is looking at a new concept referred to as RAS, or recycled asphalt shingles. It's a relatively new trend in road maintenance that a handful of states, including Tennessee, have tested.
Summit Hill Drive leads to the heart of the city. There's a new coat of regular asphalt on the interior westbound lane, and the other three lanes got a similar treatment with recycled asphalt shingles mixed in.
"It went down just fine. Other states have tested it for a long time. The real proof is probably 10 or 15 years out," said Director of Engineering Jim Hagerman.
But the city is already convinced. Hagerman says using five percent RAS in its roads is the way to go.
"There should be an advantage," he said. "They should be able to bid cheaper."
Hagerman says the city contracts to have about 50 miles of streets re-paved each year. From now on, companies that bid on the work have an option to use RAS.
"Because of the fiber content, it lasts a little bit longer. It is a little bit stronger."
That means pesky potholes could be reduced. Research has shown the RAS mix uses less energy, has lower greenhouse emissions, and re-uses something that usually ends up in the dump.
However, there is one challenge: "Converting shingles that are torn off an existing building mixed in with other stuff, nails and pieces of wood," explained Hagerman.
That's where Knoxville Shingle Recycling comes in. Earlier this month, 10News reported its efforts to help a West Knoxville landowner clean up his property after a fraudulent shingle recycler filled it up and skipped town.
"We would like to get rid of those piles, and this is a good way to get ride of them," said Hagerman.
He says there's no agreement between the city and the recycler, but the recycler is working with area asphalt producers to buy the processed material. The asphalt could end up on city streets-- going green and saving some money too.
Hagerman says the bid for the paving contract with the recycled shingle mix option opens Thursday. It will be several weeks before a committee chooses the contractor for this year.