Not sub-zero but 4 degrees. I almost drown during a duck hunt a few weeks ago.

Driving wind blowing from the North. I launched my kayak to recover some ducks I'd shot. Water was calm in the lee of the North shore cliffs, but when I got out further the wind caught the kayak, lost sight of shore in the fog, water turned to whitecaps, and I was not able to fight my way back into the lee of the cliffs. Stupid! Stupid! Stupid! I was forced to take a tack where the whitecaps wouldn't breech into the boat.
More than an hour later I made it into the surface slush that had not yet turned to ice in the flooded tamarisks on the West end of the reservoir. From there I worked my way to solid ground which took about another 45 minutes.

The REALLY scary part came when I was safe on shore. My light kayak had built up so much ice that it was too heavy to pull up the slope of the shore. I knocked more than 150 lbs of ice off the boat and realized I had been riding way too low in the water for the choppy conditions that day. It wouldn't have taken very much more ice to do me in ... and all to try to recover a stupid duck.

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