How Highway Noise Barriers Can Make Traffic Louder - Cheddar Explains

Highway noise barriers are intended to reduce traffic sounds for nearby residents and businesses. And there are over 3,000 miles of these walls lining U.S. highways. However, recent studies show they might not work as well as intended. And could actually be amplifying noise in some locations.

Further reading:

Undark

Jalopnik

Smithsonian Mag

Sound Walls


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[_ikako_]

As any City Skylines player will tell you, trees are the best solution to noise pollution. Not only do they have far more surface area to absorb sound over, they also have the added benefit of absorbing some of the pollution from the cars on the road.

[tbthegr]

In Sweden, all noice barriers I see is made out of wood, and shaped in a way to try to catch and trap sound. Where each piece of wall is an S-shape, where I assume they aim to trap sound in the "boxes"

[bgovetas]

Diffusion and absorption are the way. Reflections literally create an echo chamber. Physics are cool

[NotJustBikes]

Huh. I was just researching a video about urban noise. This is good timing!

[sabikikasuko]

So basically, concrete is so convenient that even after it's been proven that it not only doesn't work, but it makes the traffic noise *worse* and more deafening, the state won't do anything because doing so is a pain in the ass.

Yeah, sounds about right.

[nixboox]

This is exactly what happened by my house. The side closest to the road needs to be made to look like recording studios with sharp pointed angles to break up the soundwaves instead of just flat surfaces for the sound to bounce off of and spread out.

[danielantoniozd]

I grew up near a major hwy, even at 200 feet I could still hear it.
Now I need it as whitenoise to sleep.
I don’t like a quiet house at night.

[cSkylaneRG]

Sooo.... what about trees? Plant a good 20-30 ft thick row of trees, make sure they're a fast-growing, dense-foliage species of evergreen. They take care of themselves, they're soft so they absorb the noise, and the dense foliage and 20-30 ft thick row makes sure that there aren't large holes for sound to pass through. Drivers get something green to look at, instead of grey, residents get something green to look at, instead of grey. Road noise isn't refracted over the barrier, it isn't reflected back on cars, and we get a 1st stage filter on all the C02 being produced.

[mcmurdo]

Trees and bushes combined make for the best sound barrier and they have environmental benefits like cleaner air

[Lunavii_Cellest]

in the netherlands we build hills out of earth next to highways to have reduced noise whilst it looking better and also working better

[murdelabop]

Not building interstate highways through residential areas would probably also be a good idea.

[minion]

typing from nottingham uk. trees and hedges they do exactly what you need them to do, look pretty and reduces noise

[philplasma]

Highway, then train tracks, then thin row of trees. That's what I have to deal with; no concrete noise barrier and apart from when the engine part of the train passes the noise I get from the highway and the train tracks are well within my comfort zone.

[far]

I used to own a house a couple homes next to the freeway. Since we were on a hill you could not see it. Pretty everyone that came to my house would ask where is the river ? It sounded like a running river. I am happy I no longer live near the freeway.

[oblivion]

The different types of asphalt/"pavement" make a HUGE difference. We have two types here in Germany. If a highway (Autobahn) section needs to be replaced, they use the "new" less noisy type. You will notice the severe change in noise when driving from the old road onto the new one. Its less than half the noise at least, as far as I can tell.

[santiagoescobar]

Maybe the ussage of trees will do the same intended purpose but also improving air quality... don't know why it is not used already

[krisP]

I noticed this in the small town I grew up in. There was a railroad track going through town in a deep trench. When the train would sound it's horn it would be extremely loud and annoying. I always wondered why they didn't just put the train tracks on level ground. Also, the house I live in now has the highway noise problem. We are 150m or 492ft from the highway barrier and the sound is deafening at times. Honks, sirens and street racers can be heard as if they're right outside our house. I hate being outside in the afternoon especially when trying to have a conversation.

[thomaswalsh]

“Depending on distance, noise can reach 70-80 db at 50 feet” nice contradiction on the opening line

[CharlV]

In the Netherlands, there are glass barriers at some locations in the city. It's also angled and not 90 degrees. Don't know much about it but it seems very effective. They also use a lot of greenery and it seems to help as well.

[stevemc]

"You have become the very thing you swore to destroy."