I was walking besides a part of Crowchild Tr. and got the chance to get really close to the wall the Municipality has put up to protect the nearby residences from the continuous noise of the road. I don't know how efficient this wall is. The residents of the neighbourhoods close to such major roads should say but getting very close gave me this chance to realize that they are not concrete walls unlike I had thought originally.
The first impression someone might get is that the municipality has put of concrete walls but this kind of wall is very heavy so would have been very expensive to build and install, had they have used them but a good close up shows they are made of a kind of pressed material maybe pressed wood chip. If that is the material then I assume they are good noise barriers but planting trees is another good sound reflector but they need to be really dense. That was my observation today! Noise is a real problem in the city and one of the reasons that I hate Downtown, particularly in summer that you have to leave the windows open, is the annoying noise.
(Photo: A close-up of part of noise-proof wall alongside Crowchild Tr. in Calgary. Cut and chipped material could be easily seen. This kind of wall is seen around a few other major roads of the town, including Highway # 2 to south and Highway # 1 to west after C. O. P., etc.)