GRAND RAPIDS, Minn. - The boat is old, but the motor is new. And experienced boater Dave Koepp just wasn't used to the way the new motor jerked while slowing down early Saturday morning when he was out on Pokegama Lake in Grand Rapids, alone, with his dog Mac.

“The momentum tossed me right over the side of the boat,” Koepp said.

Dave was treading 46-degree water as his boat circled him like a shark.

“When I popped up out of the water, I couldn't see the boat. And as soon as I turned around, I could see it coming right at me,” Koepp said.

The boat's propeller sliced through his arm, requiring eight stitches.

And in the water, Dave was quickly losing hope.

“I looked to shore and knew it was at least a quarter mile away. And thought, I'm going to try, but I don't think I'm going to make it,” Koepp said. “A lot of old memories come flooding back.”

Dave's thoughts went back 22 years to when his cousin, a 10-year-old boy, died in a boat accident on a Minnesota lake.

“The minute I hit the water, I thought of him. And thought, 'I can't believe I'm going to leave this world the same way he did,'” Koepp said.

Aaron Sahli's death prompted state law changes regarding children operating boats. And the lives of Dave and his family were never the same.

But Dave wasn't destined to die on this Minnesota lake.

“Somebody was watching out for me. Whether it was him or God or a Guardian Angel or whatever,” Koepp said.

Dave, soaking wet and suffering from hypothermia, was pulled aboard another boat by three men. They then disabled the circling boat by pulling the kill switch - a safety device Dave failed to clip to his belt -- a mistake he says he'll never make again and wants to warn others about as well.

“I've said it a million times. I'm not falling out of this boat. I’ve been in it too many times. I know it too well. It's never going to happen to me. And it did,” Koepp said.

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