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More of a wilderness topic...

How thick does ice have to be on a frozen lake for it to be considered safe to walk on? I ask this because today I walked across my first frozen lake. It wasn't for fun, rather walking across it happened to be the most direct route to where we were going (it was Mitchell Lake, in the Indian Peaks, Colorado BTW). I knew the ice was solid because this particular area had not been above freezing for several weeks. There was about 8 inches of snow on top of the ice, and I stomped on it a bunch just to make sure to was good...solid as a rock. I think I heard once that ice that is 12 inches thick is strong enough to drive a truck on and I believe it. But what would be the minimum thickness safe enough for walking on?

The best rule I can suggest is to wait until spring. The dangers of a thawing lake are far more obvious than those of one in the process of freezing. And of course snowshoes or skis are preferable to just your boots to distribute the weight. Ski poles can be used to probe the ice ahead of you if needed.

Rule #1: DON'T FALL IN!

The rest don't matter....

Attached are a couple of PDF Fact Sheets:

The 1st includes Minimum Ice Thickness for New Clear Hard Ice:

http://www.lifesaving.org/download/Choosing%20safe%20ice%20surfaces.pdf

http://www.lifesaving.org/download/Ice%20Myths.pdf

Years ago as a kid I used to skate on frozen lakes. It took awhile to get used to skating on clear ice and seeing the plant life moving around below.

I test the thickness with an ice screw if it takes a 16 cm I go for it...but this is not a clean rule...
That said, I try not to walk on frozen surfaces until January normally here in the North East...
And this because a couple of year ago I fell in Chapel Pond in the Adirondacks (without consequences..) because it was to early in the season to walk on it..

1000Pks wrote:(a MLC SC trip, BTW)!

Goes without saying, naturally.

btw, have fun in Vegas next week. Hope you don't have too much snow.

1000Pks wrote:Basically it's best never to ski or snowshoe or hike on any lake ice. . . .

Agree with that. I personally wouldn't walk across a frozen lake. It might be a foot thick at the start but very thin out farther due to a multitude of variables. Who knows. It's not worth the risk, in my opinion. The consequences are way too big.

When I was a teenager, I was in my friend's car when we drove out onto frozen ice in Anchor Bay, which is part of Lake Saint Clair, a 430-square-mile lake in the Great Lakes system. A couple of stupid rednecks we were, of course, along with a hundred other people that were doing the same.

Idiots drive out there and set up ice fishing shanties, so they can freeze their balls off sitting on ice, fishing from a polluted lake, when there are good fish in the grocery store for a few bucks. I guess some guys will do anything to get away from their wives for a day.

Here are some examples of how genius it is to setup a structure on a frozen lake:







But I know they drive on frozen rivers in Yukon in the winter. I suppose they consider it safe enough when the temperature sometimes gets down below minus 50F.

But then again . . .

When I lived back in newburgh NY I heard that people back in the old days would walk across the Hudson river when it was frozen. That's a 2 mile walk across atleast

First here's some info. http://www.mvp-wc.usace.army.mil/ice/ice_load.html

If you know how the local conditions were on freeze up and you know how much snow is covering the ice, then ideally you should test the ice for thickness at least every foot or two. It's tedious,takes a lot of time and doesn't guarantee the ice is safe. Be prepared to get wet, have a plan for getting out and be lucky.
I have traveled a lot on lake ice and river ice, and I have had ice rescue experience. It is scary. If you can avoid it or you are traveling with someone with a lot of ice experience, take the long way around.

Rule #1 : You first

Day Hiker wrote:[ I personally wouldn't walk across a frozen lake. It might be a foot thick at the start but very thin out farther due to a multitude of variables. Who knows. It's not worth the risk, in my opinion. The consequences are way too big.

It can be mesmerizing, not unlike an exposed class 3 route that can be completely avoided but we choose not to. And I don't think the main reason is to save time, for me anyway. It's part of the adventure.

Carl Heller?

Very good:



Good:



Not so good:



Not good at all:



Seriously, the last week did a lot to make lakes like Mitchell safer to cross. I was up in Glacier Gorge these last two Saturdays and noticed quite a difference. On the 5th, I wouldn't have crossed Black Lake (which is about the same elevation as Mitchell), but on the 12th I had no qualms crossing Mills and Jewel (which are lower than Mitchell). Yet, at the inlet of Jewel it was still a bit slushy.

Thanks for the info guys, just wondering if what we were doing was safe or not. I felt that the crossing was very safe, personally, but the links and stories provide good insight.

Here is the lake we crossed, temperature was ~20 F.

The rule of thumb in Wisconsin (ice country) is that 4" of ice is thick enough to drive a car over.

My father lives in a small town which has a ferry crossing during 3 seasons. In winter they pull the ferry boat out and the locals just drive across the Wisconsin River. They make wagers to see who can be the first, and last, to cross for the year. (Seriously.)