General Road and Highway Discussion

[MacBerry]

Can someone explain why the noise barriers on the new 7/8 overpasses (Westmount, etc.) are transparent (acrylic?) and different from the rest of the barriers along the 7/8?

Is it purely for aesthetics? Safety reasons? Better lighting? To allow for greater solar snow melting in winter? Cheaper? Better sound abatement?

Thanks.

I believe it is about keeping "taggers" away. Being visible while tagging means a greater chance of being seen or getting caught. Clear panels also do not give a background to display said "art".  Finally, it is I believe, cheaper to replace a panel would also be a factor.