I'm in the Fort Erie, Ontario area and we installed a 19x35 Grecian-style in-ground pool this summer. Construction started in June and we were able to start swimming in late July. Luckily, we had a warm summer and managed to have water temperatures in the 75-80Â°F range until September. Rather than using a gas pool heater, we opted to go with a shell & tube heat exchanger with hot water provided by our outdoor wood furnace (also installed this year). I was heating until November 6 and manage to achieve around 75Â°F but this took a lot of wood. With the air being so cold, we only managed to swim one last time in November so I think we'll be closing the pool earlier next year.
Because our backyard sloped away from the house, we still have a lot of landscaping to do yet. The excavated soil still surrounds the pool but we've already used up a good part of it with landscaping. With luck, it'll all be gone by next summer.
The piping installed by the contractor is a bit ugly so I will be redoing it - maybe even within the next few weeks if the weather holds. I have some questions about valves and fittings and I'll post some topics in the Pumping Station shortly.