sigh This story has been in and out of the news for decades. It's a troll story, don't worry! First off, where are they going to find a leisure centre near enough to a crematorium to make this viable? Secondly, a crematorium only makes heat when it is taking care of a deaceased person, which is only a fraction of the time, so wiring it up to a pool, with all the heat loss on the way over, would be utterly useless and inconsistent.
In other words, it's there to make people whine over nothing. And it's worked!