The state will spend $14 million to line portions of two major metro Atlanta interstates with new sound walls, and Channel 2 consumer investigator Jim Strickland has learned there are no plans to actually test whether they'll do any good.
Olivia Brown lives behind a newly finished wall off Interstate 20 in Decatur. It is part of an $8 million project.
"I think it's ridiculous. They could have kept the $8 million," she said.
Neighbor Ronald Maddox said he doesn’t hear a difference.
"It's the same," he said.
During the interview, Strickland heard a blaring siren as an ambulance drove past the other side of the wall.
Maddox also said the wall makes him feel imprisoned in his own yard.
"God made me free, and I feel I should be free to see. I feel blinded," he said.
Georgia Department of Transportation environmental chief Glenn Bowman admits not all residents are satisfied with the walls, adding that others who want them complain when their neighborhoods do not qualify.
"They are controversial. There's no perfect solution to this," said Bowman.
To receive federal money for highway construction, the state must follow federal rules on highway sound.
Whenever a new project is designed to increase traffic flow or bring traffic closer to residents, a sound study is conducted, said Bowman.
Strickland found a construction crew building a section of wall that will shield nothing but trees.
"There's no houses or anything, and they're putting up sound barriers. For what? The animals don't care," said Brown.
But News Chopper 2 aerial surveillance showed an abandoned subdivision nearby. The rules assume houses will come.
"We don't plan for just tomorrow, we don't plan for just next year. We have a 20-year horizon," said Bowman.
A wall planned for Interstate 85 in Newnan will shield the golfers at Cannongate Country Club.
"It is an area of frequent human use, and it can be distracting to have noisy vehicles driving by," said Bowman.
State analysts plug in numbers such as traffic counts, land use and population when planning for a new sound wall. A special computer program sorts the data and decides whether a wall will do any good to protect an area from noise.
Regulations demand it cut traffic noise by 5 decibels. Bowman said that equates to the noise from a leaf blower on full power from 100 feet away. Nothing in the rules mandates a test to see whether any wall really makes any difference after it is installed.
They are designed to work, so the assumption is they do work.
"We just don't believe that it's necessary to test every site," said Bowman.
Strickland acquired a sound meter and found a perfect test spot in Clayton County. He took measurements in the neighborhood protected by a metal wall and along the roadside nearby where there is no wall. After pacing out 50 feet from the guardrail, Strickland measured the average sound level over a 60-second period. The meter took a reading five times per second and measured the average sound level with no wall at 66 decibels.
Repeating the procedure earned the same result. The minimum sound level that qualifies for a sound wall is 66 decibels.
The same procedure behind the wall found not much of a difference: 64 decibels. The test was designed as an "apples to apples" comparison, not a scientific study.
Farther down Interstate 75, there is a concrete wall behind Jared Mihok's house in Stockbridge.
"As they went up and up and up, it got quieter and quieter and quieter," said Mihok.
Strickland and his crew could tell an obvious difference in the sound level compared to the highway on the other side.
Unwalled traffic noise there averaged 73 decibels. Behind the wall it was 59 decibels.
"Before, you and I couldn't have a conversation like this. We'd have to be 3 inches from each other. They put the wall up, and it's great. I love it," said Mihok.
Beginning this summer, I-85 in Coweta County gets more than 2 miles of concrete walls. The total cost is $6 million, which represents a 20 percent up-charge over metal.
The wall in DeKalb is the last major metal project in the state. Transportation officials say they have decided metallic walls are too flimsy.
"We're moving away from the metal walls. Our commissioner, our management, is committed to move away from those that are not as durable," said Bowman.
Strickland found gaping holes in several metro-area sound walls. Two holes along I-75 near Moore's Mill have been there for at least a year. DOT fixes sound wall damage whenever time and resources allow.