Teenagers shooting out lights and cutting fences for midnight swims are hurting public swimming pools, says a pool manager.

Calgary's outdoor swimming pools are struggling to stay afloat and repair bills don't help, said Bowview Outdoor Pool's Justin Kim.

"It's kind of disappointing to see some of the incidents that occur here. Because really we're just here for the community and when you're bringing it down, you're not really helping anybody."

Neil, a 19-year-old, says he and friends hopped a fence to go for a swim in a public outdoor pool, said he doesn't see the harm, even when neighbours call police.

"As we were out of the pool, the cops showed up right away, but the thing is we were all walking with wet hair and stuff and they can't really do anything," he said.

"I think it's cool because it's kind of unexpected. It's a good way to end the evening, I find, and it's a good summer pastime."

But other young people are cutting the wire fences to get in and leaving broken glass and beer bottle behind. At the Bowview pool in northwest Calgary, the lights were shot out with a BB gun.