I went swimming in an outdoor lawrence heights community centre recently. I was expecting the worst for every good reason. This pool is rated a "C" in the city government website. It was nice sunny day and in a crowded housing project. I thought it would be really crowded. It turns out everything was actually nice. The facilities were clean and functioning. The water was clear and perfectly warm. Even my bike wasn't stolen while i was swimming.
see City of Toronto website pool rankings.

But yes there are plenty of good reasons to get your own pool.
A Canadian study by the University of Alberta showed that there is an average of 75 litres of urine are found in the regular size public swimming pool. If you thought the professional Olympic size pools were any better you are mistaken. Then there are smaller more obvious reasons to have your own pool like: hours/life-guard, peace and quiet, convenience. Even though this fact wasn't visible to me I was able to see an occasional hair or something in the water.
For someone like myself who only likes to go swimming once a month can probably put up with the public pool. However I realised that even people like myself, If have a backyard why not put in a pool for just over $1000. Above ground pools from Discount Pool Supply are quick to install and easy to remove if necessary.