I drove there for a weekend ski trip during the winter: Winter Driving Experiences - Page 126 I charged at the underground parking lot of the Grande Georgian Lodge using the standard 110V outlet, they have a lot of those in the parking. The other option is that you can make a detour to hit Barrie on the way back and use the supercharger (it was not open at the time of my trip). But in the warm spring weather, you can probably make the round trip from Toronto without charging too.
I made the trip to Collingwood and then Thornbury nearly every Friday. In the brutal winter cold I had to charge at Barrie Supercharger both coming and going. Now in the warm weather a one time charge there would get you there and back with plenty to spare.