Highway sound barriers block pollution, too
It turns out those big concrete barriers put up along busy highways to shield neighboring residents from the roar of traffic also reduce how much air pollution they get from the passing vehicles.
That's what a new government study found, anyway. Researchers with the National Oceanic and Atmospheric Administration and the Environmental Protection Agency released harmless "tracer" gases along highways to track how they were dispersed through the air - and by extension, indicate what happens to harmful pollutants such as carbon monoxide, soot and benzene that are emitted by cars and trucks going by.
The researchers found that in addition to blocking out sights and sounds of traffic, the barriers apparently channel air flow - and many of the pollutants - up and away from nearby residential areas.
"We also found that the barriers tend to trap pollutants in the area of the roadway itself, especially at night in low wind-speed conditions," said Dennis Finn, a NOAA meteorologist from Idaho, and lead author of the study, published in the journal Atmospheric Environment.
That ought to be an added relief to residents sleeping in homes shielded from highways by those barriers - though if you're on the highway you may not want to breathe too deeply or stay long if you find you have to stop your car on the shoulder in one of those concrete sound-barrier canyons.
(1998 Baltimore Sun photo by Lloyd Fox of sound barrier being built on I-695 near US 40)
Comments
We just built a house and are about 2000 feet from the interstste. We get a lot of road noise most days.Was wondering if you could tell me if a high berm or high fence or concrete arround the house would hepl our noise problem.We have also discussed putting trees arround the house.We dont know what would be the best solution.do you have any ideas? Thank you. Keith Aslett
Posted by: Keith Aslett | December 16, 2009 1:04 AM
Trees! Plant trees! Evergreens & deciduous. They dampen noise rather then just reflect it. They reduce pollutants rather than just channel them. A earth berm or wood fence wont be high enough, and a concrete wall looks ugly , it would have to be quite tall, will have to be permitted, engineered, and constructed properly due to the height, and will need maintenance. Trees are cheaper, even with pruning/checkups once every 5-10 years.
Posted by: env.chemist | December 16, 2009 11:30 AM
Thanks so much for the info. The wife was happy to hear trees was the best.Sounds like it is much better and we have been in a delima of what to do.We did not realize how distracting and irritating the noise could be.
Posted by: Keith Aslett | December 16, 2009 3:00 PM
2000 feet? Try 100' where TREES simply don't work. It's estimated that a 200' deep barrier of trees could possibly neutralize the sound and pollution. We welcome the ugly concrete wall, then we'll plant ivy and other cover to grow on the wall. Trees aren't the answer to everything. The evergreens planted initially along the border fence to our property mostly died. They did very little other than hide some of the highway. The dirt on our houses is awful. One must stand toe-to-toe to speak with your neighbor. One must close the windows to have a phone conversation. Ever see an aerial photo of the foilage destruction on each side of a highway or the entrance and exit paths of an airport? TREES! Good grief.
Posted by: Paul Rauser | December 17, 2009 10:37 AM
Planting trees are better solution to shield us from pollution. Grow trees and save our earth.
Posted by: jack hooper | May 9, 2011 1:58 AM