LEWISTON — Thomas Page and Betsy McGrail spent the summer at their Cobbosseecontee Lake camp, looking for dark clouds and choppy water.

“When it’s rainy, when it’s windy, when it’s cold, we go swimming,” Page said. “You’re basically thinking, ‘What are the worst conditions that I can have in this lake?'”

The couple hopes their worst conditions — approximating a stormy day in the ocean — might make this weekend’s wet enterprise a little easier.

“You don’t want to be too nervous,” Page said of the ocean. “If you get a big mouthful of water, it’s scary for anybody.”

And on Saturday, it’s for the money.

The Leeds couple and a friend, Doug Breunig of Auburn, will join 600 swimmers in the Alcatraz Invitational as they swim from Alcatraz Island in San Francisco Bay to Fisherman’s Wharf, about one and a quarter miles away.

With their swim, the three hope to raise about $10,000 for the YWCA of Central Maine. All three use the East Avenue facility’s pool.

“When the Y came very close to closing its doors, I realized what a valuable asset to the community this is,” Breunig said. “I want to see it continue.”

The San Francisco swim wouldn’t happen without the YWCA, Page said.

“It’s only doable because we get to swim at the Y to build up to this,” he said.

The idea of the swim came up as a way for the three people to celebrate their milestone birthdays. In 2001, the guys swam from Peaks Island to Portland. It was Page’s 40th and Breunig’s 50th.

A decade later, they were looking for another challenge. Breunig half-heartedly mentioned the Alcatraz swim

“Tom actually thought it was a good idea,” Breunig said. “So now what do I do? No way out.”

They signed up in January.

McGrail joined them because her 50th birthday was coming around, too. And they set about training, swimming the Sebago Lake Challenge and the Rockland Breakwater Swim to get a taste of open water.

They expect two- and three-foot waves in the bay for their 9:15 a.m. start.

For McGrail and Page, former triathletes, it’s a chance to push themselves a bit. 

They won’t actually set foot on the island home of The Rock, the former prison that once hosted Al Capone and George “Machine Gun Kelly” Barnes, among others. Rather, they will jump from a ferryboat beside the island and swim for the shore.

They’ll have two hours to complete the swim but they expect to finish in about half of that.

“If you didn’t swim, you wouldn’t try it,” Page said. The water will be cold — about the same as Maine — and the currents are rough. But the mile and a quarter distance is reasonable for a regular swimmer. “It’s really not that formidable.”

Breunig, who is also in fine shape, is a little more tentative.

“I look forward to it, but I will be happy when it’s over, too,” he said. He plans to spend a few days after the swim in nearby Napa Valley.

“A friend of mine sent me a couple of articles recently about a 7-year-old kid who did this swim and also a golden retriever,” Breunig said.  “I’m thinking a 60-year-old guy who’s in reasonably good shape ought to be able to do this as well.”

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