Berlynn, I also remember whiffs of open sewage in Toronto when I was last there in the spring of 2011. This was in May, just after the Federal elections - we were discussing the new situation with the election of the Cons but also, for the left, of the large NDP caucus. Some of us were attending different events on behalf of Québec solidaire. It was later in the springtime, but strangely cold (after a very, very warm April) so we didn't eat outdoors at all, but the smell was disturbing. Thought it was because there had been a lot of rain - or perhaps one of our Torontonians can tell us if there are sewer problems there.
Our main water/sewer problem is leakage. The water system is antique and wastes a lot of water. I know parts of Mtl actually released raw sewage into the St-Laurent some years back, but think that is no longer the case.