On June 28 the Toronto Port Authority, or Toronto Ports as they like to call themselves. held a community meeting to consult on the noise enclosure that they are planning to build.
Max Moore, a sound engineer who lives on Bathurst Quay, was at that meeting and has examined the proposal in some depth. This is a letter he wrote to Councillor Joe Cressy explaining why he feels the sound enclosure is totally inadequate.
Editor’s note
For: Joe Cressy, Toronto City Council
Re: Proposed Airport Noise Enclosure Problems, July 8, 2016
I have reviewed the proposed island airport run-up noise enclosure, and conclude that
it’s an expensive public relations gesture that will not reduce noise in the neighbourhood.
model of the proposed noise enclosure
The problem is in the design. The Port Authority has hired a firm that designed a noiseenclosure to meet the Port Authority specs. This suits the airport’s needs to look good inthe eyes of the media, but does not meet the community’s needs for less airport noise.
Basically, the proposed noise enclosure does not enclose the noise. The design, as
proposed, is a hollow wall, not a solid wall. Inside the hollow wall are panels which will
direct the noise and the air flow upward, into the wind, which will carry the noise into the
neighbourhood, exactly the same as it does now. And more run-ups mean more noise.
Acoustically, the only thing the noise enclosure offers is a few sound muffling materials,
which will reduce the noise, as it passes through the enclosure, by maybe 10-15
decibels. This is not much of a noise reduction when we consider that the noise of
engine run-ups, at the source, is 120 – 140 decibels, which is as loud as thunder.
Background Info
In studying airport noise problems, we have learned that engine run-up noise is at its
worst when the wind blows in our direction, and when cloud cover and/or humidity
amplifies noise levels. When there’s no wind, we don’t hear much noise from the airport,
but when there’s a wind in our direction, it’s louder than hell in our neighbourhood, from
6 am until nearly midnight.
Noise travels with the wind, and the proposed noise enclosure simply re–directs the
noise upward, into the wind. This design will make the noise problem worse on windy
days. It might reduce noise a bit on non-windy days, when we don’t hear noise anyway.
To illustrate the problem, it’s possible to compare the proposed design with an ideal
noise enclosure design. Ideally, a run-up enclosure would be shaped like a horse-shoe,
ie. solid, rounded walls, with a curved lip at the top to reflect the noise back into the
noise enclosure, and toward the ground at the center of the noise enclosure.
I suggested this ideal noise enclosure design to airport officials and was told that it
wouldn’t work for the airport, because plane engines would stall if run-up noise was
reflected back at the plane. Because the plane needs free flowing air to do an engine
run-up, the proposed noise enclosure lets the air pass through the so-called enclosure,
and is redirected upward into the wind. That’s solves their problem, but it ensures that
the neighbourhood will still hear the full blast of every engine run-up when the wind is
blowing in our direction.
I hope you can advise the Pork Authority to revise their specs, and ask for a noise
enclosure design, which actually helps the neighbourhood, instead of spending millions
of dollars on a public relations exercise which won’t help anyone.
Max Moore, Harbourfront Community Association