SAN FRANCISCO (CBS SF) — Wealthy U.S. businessman and environmental activist Douglas Tompkins died Tuesday from severe hypothermia in a kayaking accident, Chilean authorities said.

The Aysten health service said the 72-year-old Tompkins, who was a co-founder of The North Face and Esprit clothing companies, was boating with five other foreigners when their kayaks capsized in a lake in the Patagonia region of southern Chile. Tompkins died in the intensive care unit of the hospital in Coyhaique, a town 1,700 kilometers (1,056 miles) south of Santiago.

Chile’s army said strong waves on General Carrerra Lake caused the group’s kayaks to capsize. A military patrol boat rescued three of the boaters and a helicopter lifted out the other three, it said.

After retiring in 1989, Tompkins was active in conservation and environmentalism. He owned hundreds of thousands of hectares (acres) in Patagonia, a sparsely populated region of untamed rivers and other natural beauty that straddles southern Chile and Argentina. On his Chilean land, he created Pumalin Park, 290,000 hectares (716,606 acres) of forest, lakes and fjords stretching from the Andes to the Pacific.

Hiking enthusiast Tompkins opened his first mountaineering store in North Beach in 1966. The North Face was an immediate hit with a young crowd. The Grateful Dead once performed inside the original store.

The store was the first to sell high performance climbing and backpack gear. It eventually moved to Berkeley and expanded throughout the world. Tompkins also started other businesses along the way. He founded the Esprit clothing company with his then wife Susie Tompkins in 1968.

Janin Inman of South Lake Tahoe was a clothing seller who worked with Tompkins.

“I met him because of his original company Esprit,” said Inman. “He had a great warehouse and he had a great product. He and his first wife had Sweet Baby Jane and different companies in the ’80s.”

The North Face is now owned by VF Corp. of Greensboro, North Carolina.

TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten. The Associated Press contributed to this report.