That is one consequence of the community trust. Since only one or two houses go up for sale a year, it can take 30 years on the waiting list to buy a house here. By then, many buyers are already into retirement age.

The irony, of course, is that the park is the ideal place to be a kid.

Julian Ganton, now 31, recounted summers spent sleeping in tents high in the trees and winters spent playing shinny — that’s Canadian for pickup hockey — right outside his house.

He laced up a pair of skates and climbed down a ladder onto the frozen harbor, where he cut over cracks and frozen methane bubbles. A hockey stick in hand for balance, he pushed off toward the middle of the harbor.

Toronto city officials are not the only ones to put out reports on ice conditions. So do the islanders. As a rule, they say that three inches thick is safe to go on, two inches if it is bitterly cold. When Mr. Ganton went out, it was at least one foot thick — 18 inches, in Mr. Webster’s estimation.

Even so, the sound of the ice groaning and cracking made Mr. Ganton’s heart jump — with both fear and delight.

“You never get used to it,” he said. “It always fills you with awe.”