CHARLOTTE, N.C. -- More noise walls are expected to go up as part of the I-485 widening project in south Charlotte.
Neighbors in spots where walls are already up say it's hard to tell if they're making any real difference.
Lisa Wines has one of the best views you'll find of crews putting up the walls.
"It's right outside my back door," Wines said.
Big cement blocks replace trees as the barrier between her Pineville apartment and the interstate.
It's not exactly what you'd call aesthetically pleasing, but looks aren't the point.
Reducing traffic noise is.
The NCDOT says the walls will reduce traffic noise by five decibels.
What's five decibels?
Experts say it is enough to notice a difference, but along the lines of whispering or leaves rustling.
75 decibels is about normal for highway noise, professional websites say.
The highway hum is part of life in Qucavon Covington's neighborhood.
"You can hear the cars go by," he said.
He likes the walls, but says his mother prefers a view of the cars.
"Quieter is quieter. I prefer quietness over loudness any day," Covington said.
Overall, there will be about 9,000 feet of noise walls. Most will be on the inner loop. The area around Johnston Road and Elm Lane will have them on the outer loop.
A fourth spot, still in design stage, is set for the inner loop at Rea Road to ease noise near the Piper Glen area.
Money for the walls is part of the already approved $83 million widening price tag.
Neighbors say it's hard to tell if they're making a difference now.
"Not really," Covington said.
But they're not all finished and the real test of their effectiveness is yet to come once all lanes are open. Volume, speed and the number of trucks are the recipe for noise, experts say.
All noise walls will be in place by December, which is the same month the entire widening project is scheduled to finish.