Ask Gary Thompson why people break through the ice, and he'll say they usually don't do a good enough job of testing it before they venture out.
There's more to "reading" ice than measuring how thick it is. The Eskimos of the North have more than 100 different words for snow, Thompson says. And while his vocabulary for describing ice is less extensive, it's no less accurate.
There's clear, black ice; milky ice; honeycomb ice -- which is fairly good until there no longer is water visible on top of it, Thompson says -- and finally, there's the ice he puts in the "oh (expletive)" category.
"That's when you go through," he says.
Owner of Tri-State Diving in Detroit Lakes, Minn., Thompson, 69, often gets the call when people experience the sinking feeling that results when vehicles, fish houses, ATVs, snowmobiles and who knows what else end up on the bottom of the lake or river.
Thompson, who in 2008 was featured on an episode of "Dirty Jobs" with Mike Rowe, recently wrapped up his 50th year of diving.
The Ada, Minn., native says he's pretty much seen it all over the years.
"What we're finding now, more than anything else, is side-by-sides, four-wheelers and the big wheel fish houses" breaking through the ice, Thompson said. "People are getting smarter in some ways -- they're not taking a three-quarter ton pickup or 1-ton 'dualie' (pickup with dual wheels) out there and pulling their houses around on the ice. They just get too much weight in a small area."
Thompson, who aptly is nicknamed "Seal," says Tri-State Diving does anywhere from 10 to 15 salvage operations in a typical winter. As of mid-January, the company already had pulled nine ATVs, vehicles or fish houses from lakes across the region, and more jobs await them when weather conditions improve.