QUESTION: How thick can the ice get on Lake Tomah?
ANSWER: As of this writing on Feb. 14, 2021, the ice is about 15 inches thick on Lake Tomah. The Wisconsin Department of Natural Resources does not provide information on lake ice thickness. They have some general recommendations. Four inches should hold a man, five inches will likely hold a snowmobile, eight inches will support a car or light pickup truck. To cover themselves, they do not recommend driving anything on the ice.
The DNR also says that bait and sporting goods shops, plus snowmobile and fishing clubs, know a lake’s history and nuances and share information with locals and visitors about changes in the ice or spots to watch out for. The DNR says, “Locals may know where to go for the most up-to-date information, so if you’re visiting, do your homework ahead of time on whom you can contact. There are too many variables, like the wind, current and temperature, to give out a safe minimum ice thickness for different weights on different lakes.”
Ice is rarely the same thickness across a body of water and changes often. Don’t go in areas that you’re not familiar with. Checking ice thickness is as easy as standing next to the guy with the ice auger and asking him.
Seems every year we hear of cars or trucks going through the ice on Lake Onalaska, just north of La Crosse. There are a few memorable ones in Wisconsin. On Feb. 27, 2012, 36 cars went through the ice, 18 fully submerged, at an ice fishing contest on Lake Winnebago. There were no injuries. The cars were all parked together, like in a parking lot, and the ice couldn’t take it. On Feb. 7, 2016, 15 vehicles fell through the ice on Lake Geneva during the city’s Winterfest celebration. Dive teams were called in to get them out.
Experts provide a few tips: Don’t go in areas you are not familiar with. Avoid areas that have cracks, or moving water, such as springs, inlets or outlets, and runoff during a warm spell. There’s clear black ice, milky ice, and honeycomb ice. Milky and honeycomb ice aren’t as strong as clear black ice. Don’t drive fast on the ice as you are creating a wave under the ice and that can destroy the ice. Avoid areas with cattails, which can weaken the ice, and “current” areas where the ice is always thinner. Don’t parade in a line of vehicles. Don’t park vehicles close to each other and create too much weight in too small an area. About 50 feet apart is suggested. Go with a partner and only during the day.
Back in the day, Tomah had a contest that drew a lot of interest. An old beater car was parked on the ice by Tomah Memorial Hospital, the axle tied to a chain. Tomahans could guess the date and time the car would fall through the ice and collect a small sum of money. Even though the gas and oil were removed, the DNR forbid the car-on-the-ice caper. It was replaced by a solid block of concrete, also tied to shore with a chain, for easy removal. No such contest these days.
Larry Scheckel is a retired Tomah High School physics teacher.