Now, when I hear the term "breaking ground," I have many of the same associations I do with the phrase "ground-breaking." It's something new, something not done before. It's innovative. In this case, it's a new building.
But... the ground it'll be built on has been broken before. It's currently a parking lot, but given how centrally located the site is (Queen & University), I'd be willing to bet there have been other buildings on that site at some point before. So really, they aren't breaking new ground, they're breaking old ground for a new building. It's a ground-breaking achievement for the opera company, but not for the site necessarily.
I'm not quibbling over the way they've described the event, I'm just pondering the way the phrase "breaking ground" is used. It's synonymous with beginning the process of constructing a new building, but not necessarily synonymous with "breaking new ground." However, in the Second and more recent OED, "breaking (new) ground" is the given phrase.