Article

Noise Issues: Don Bly's Letter to the Windham Regional Commission

Windmills can create many vibrations and sounds at different frequencies depending on their size, the wind speed, whether the windmills are operating synchronously (in tandem or not); and whether the noise “beats” or throbs. The noise does not have to be loud to be disturbing. Pulsating low frequency noise can be very disturbing, especially at night when you are trying to sleep.

Editor's Note: Don Bly cautions readers that while he has done his homework "I should not be quoted as being a sound or noise expert".

Because of confusion about the potential impact of various kinds of noises in mountains, I would like to comment here on noise risks from Wind Farms (Factories). I hope you will familiarize yourself with this topic because construction of a wind factory could strongly impact some of our citizens in bad ways. It has done just that at other locations.

It is difficult to predict the intensity (loudness) of noise as it travels in the mountains compared to traveling over flat land. A given noise can be amplified in some areas and diminished in others depending on the shape of the terrain.

Noise travels through the air as waves. The old Victrola insignia was an ear phone. The ear phone was designed to focus sound into the ear. It has a large open cone at one end and a small tube at the other that you put into your ear. Ear phones came in a wide variety of sizes and were similar to funnels. People listened to the radio or phonograph records with them. The deaf or hearing impaired used them to hear conversations. We had no electronic ways at that time to amplify sound.

Ridges and valleys in the mountains will focus sound just like the ear phone. Sound waves travel down through valleys and between ridges as waves in the atmosphere. If the valleys and ridges converge, the sound will be funneled in and get louder just as in the Victrola cone. If the valleys and ridges diverge... [truncated due to possible copyright]  

Because of confusion about the potential impact of various kinds of noises in mountains, I would like to comment here on noise risks from Wind Farms (Factories). I hope you will familiarize yourself with this topic because construction of a wind factory could strongly impact some of our citizens in bad ways. It has done just that at other locations.

It is difficult to predict the intensity (loudness) of noise as it travels in the mountains compared to traveling over flat land. A given noise can be amplified in some areas and diminished in others depending on the shape of the terrain.

Noise travels through the air as waves. The old Victrola insignia was an ear phone. The ear phone was designed to focus sound into the ear. It has a large open cone at one end and a small tube at the other that you put into your ear. Ear phones came in a wide variety of sizes and were similar to funnels. People listened to the radio or phonograph records with them. The deaf or hearing impaired used them to hear conversations. We had no electronic ways at that time to amplify sound.

Ridges and valleys in the mountains will focus sound just like the ear phone. Sound waves travel down through valleys and between ridges as waves in the atmosphere. If the valleys and ridges converge, the sound will be funneled in and get louder just as in the Victrola cone. If the valleys and ridges diverge (widen away from the source of the sound), the sound will be diminished.

The behavior of sound waves are similar to water waves. Most of us have seen for ourselves, or on TV, how water waves behave when they enter into a gap or a channel of rocks in the ocean. The waves travel inward and pile up-and-up as they become restricted by the channel. The more the channel narrows, the greater the piling of the wave. Sound behaves in the same way. The more it piles up, the louder it gets, like in the ear phone. In some mountains you can create echoes almost as loud as the source itself, and the sound has traveled for several miles going out and coming back.

Windmills can create many vibrations and sounds at different frequencies depending on their size, the wind speed, whether the windmills are operating synchronously (in tandem or not); and whether the noise “beats” or throbs. The noise does not have to be loud to be disturbing. Pulsating low frequency noise can be very disturbing, especially at night when you are trying to sleep. How will these sounds be focused or diminished in our area? Who will get bombed? Who knows? The argument that sound drops off with distance is only valid for flat terrain.

Noise evaluation and prediction is technically feasible, but it is expensive and I have found that the builder does not want to invest in such testing. For example, I have tried to get Catamount; to evaluate my own property for potential noise risk. The basic reply I have gotten is  “don’t worry”, you live a couple of miles away. Well I can tell you, that when the conditions are right we can easily hear children playing in ponds on Upper Mountain Road which is a good 2 miles away from where we live. Fortunately that noise goes to bed when the children do.

I have heard that in other areas Companies have “poo pooed” inquiries about sound, and they assured the residents that there would be no problems. But, after the turbines were installed and the noise was there, they replied with:  that’s just the nature of the thing and there is nothing we can do about it.  Pulsing sound is driving some people literally out of their houses and they seem to have no recourse.

Many of us have seen a movie from Meyersdale PA which in part presents the very real noise problems there. Please don't let that happen here. At the very least we should require a thorough study of the potential noise effects for our area and an open discussion of the results. Personally, I would also insist on a recourse or remedy fund, and the legal teeth to make it viable. This would be set up for those people who might be driven from their homes or businesses because of very upsetting noise. Extended quiet periods are now part of the Glebe Mountain environment, certainly benefiting both wild and human life.

Again, thank you for your concerns for our community. I sincerely appreciate it.


Source: link missing! please notify us

JAN 30 2006
http://www.windaction.org/posts/1123-noise-issues-don-bly-s-letter-to-the-windham-regional-commission
back to top