If you swim at the Gleason Family YMCA, Poseidon has been keeping an eye on you.

Working alongside the staff of lifeguards, an intricate set of cameras and computers named for the Greek god of the sea tracks movement -- and non-movement -- in the pool and sounds an alarm if a swimmer is immobile beneath the surface for more than 10 seconds.

“I look at it, and I think most aquatic directors look at it, as a secondary system,” said Aquatics Director Mel Dyer said.

Dyer said only lifeguards can spot "active" drowning victims, people struggling at the water’s surface. Poseidon spots drowning victims as they become passive and slip below the surface.

“Poseidon looks for the person who is going to the bottom,” Dyer said. “Once someone hits the bottom, they’re much harder to see.”

“The nice thing is, it's hooked into a giant computer system as a whole, so we see, they see,” Dyer said. “They’re hooked in worldwide. Think of it like On-Star for pools.”

Dyer noted that Poseidon can cut guards’ reaction time to an incident. She gave the example of a guard scanning the opposite end of the pool from where an incident happens. The system would alert the guard to the incident, as opposed to the guard needing to scan back across the pool – saving valuable seconds.

Has Poseidon helped save any lives in Wareham since being installed shortly after the Gleason Y was constructed? Dyer noted that there have been no drownings or near-drownings in the pool.

“I think we’ve been lucky. We have a good guard staff, and we’ve been lucky," Dyer said.

Like any piece of technology, Poseidon does have glitches.

For instance, there have been false alarms when, during a water aerobics class, someone stands still too long. A loud alarm is, of course, one way to make sure that everyone in an exercise class keeps exercising!