For people wondering, this was not set in a future Toronto, but a current Toronto to where a character was sent back in time.
It was also an alternate reality Toronto, though it was explicitly noted to not be significantly different from what we know now, with only small changes to the timeline being made to that point.
But on to the fun part: the episode establishes as cannon that in both the Star Trek Prime Timeline (the basis of the TV shows and the pre-2009 movies) and in alternate reality timelines there was a Great Lakes Bridge that was constructed in the early 2000's that runs from Toronto across the whole of Lake Ontario to some point presumably in New York State (it is specified only that the bridge is a symbol of "International Cooperation").
The bridge is also (at least partially) destroyed in both the prime and alternate timelines, for slightly different reasons, but in the Prime timeline it was one of a long series of events that leads to World War 3 on Earth.
And yes, they have played with the start date of WWIII many times over the Star Trek franchises from as early as the late 1980's to as far out as the 2050's, but they are relatively consistent on the cause of it, though I won't spoil that part of the episode for you.