(CBS) — A University of Illinois student and graduate of Hinsdale Central High School is lucky to be alive after spending more than two days lost in the Swiss Alps.

WBBM Newsradio’s Mike Krauser reports.

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Nineteen-year-old Mark Dosa got lost in a snow storm while skiing alone. He says he followed chair-lift supports for a while.

But then he went unexpectedly into a ravine with a river. He got a foot wet and broke a binding on one of his skis.

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He says he knew he had to keep going. The former Boy Scout built snow shelters for protection for two nights.

The ravine ended in a waterfall, which he had to climb. When he heard a dog barking, he started yelling for a long time.

“It was incredible to have someone respond after not having anyone hear me for two and a half days,” Dosa says.

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He was suffering from hypothermia but was OK. Eleven other skiers have reportedly died in the Alps.