Any water cold enough to stop someones heart (I suspect you'd have to have a pretty weak heart ) would kill you just about as quickly if you stayed with the canoe and did a cannonball float - forget that idea unless you know there is someone coming to your rescue PDQ - I'd rather take my chances swimming, and at least have a chance of making it to shore.


Water temps early in september should be real close to august temps.  A large body of water loses heat  much slower than the land does (as you can tell from early winter when the lakes are still unfrozen even if there is snow on the ground).  As kids, we often went swimming in the Adirondackes in late Sept and October - the water always felt much warmer than the air did when we got out - we'd often jump back in to warm up

likewise, a large body of water will take a lot longer to warm up in the spring than the land does, so springtime is when the water is icy

an oft quoted "rule of thumb" for when to wear drysuit or wet suit is the 100 degree rule - when water temp plus air temp = 100 degrees or less.

I have never seen anyone wear a wetsuit or drysuit in Quetico, even in early May - you'd die on the portages; taking it off for portageing would take a lot of time and be really impractical.  I suppose if you were doing a trip in Voyageurs NP, a dry suit might be practical, since there are no portages.

Unless I'm doing a spring whitewater run, I don't wear a drysuit - neither does anyone else I know while canoeing (sea kayakers are the exception.  Typically, the first trip of the season is about the 3rd week in March, a multi-club group trip with up to fifty boats - I think maybe one or two people may wear a dry suit, and half? of the kayakers wear a wet suit - the rest of us just use common sense, don't tip over, and carry a change of clothes in waterproof bags in case we do flip.  Last trip of the season for me last year was in Mid-October on the Colorado R - hard frost in the morning - still didn't wear a wet suit.  I plan on not tipping over.

I've never worn a wet suit, but have seen this - a wet wetsuit is really cold once you get out of the water and into the wind -  people in wet wetsuits can't wait to get the things off.


Wally has found the best solution for a cold water swim - the sleek sea-mammal body that won't lose heat too rapidly.  Body mass has a lot to do with how fast you lose heat - a skinny little guy like me will chill out a lot sooner than a big husky guy.

I still say that people go overboard when talking about the dangers of hypothermia - if icy water is going to stop your heart, how come all the Polar Bear Club people, who go swimming thru the ice, like on new year's day, don't all die of heart attacks ?  Because they don't stay in the water very long, and dry off quickly when they get out.  So they reduce the potential risk of hypothermia.  So stay close to shore if the water is that cold, and use common sense and don't paddle in conditions that are beyond your capability.

practical reality vs potential risk - it is always possible to fall on a portage trail and hit your head pn a rock - you would be a lot safer if you wera a helmet, right?  so anyone wearing a wetsuit in Quetico because of the potential risk of hypothermia should probably also wear a helmet on the portages, just to be safe.

So of the many thousands of people who trip in BW every year, how many do you know of that have died of hypothermia there ????