Re: ancoring in open water
Hi again.... on the east side of Lake Winnipeg... yikes, I'd hate to see how rough that water would get on a stormy summer night! I thought you might have been over-estimating the wave height... but nope I'm sure that place can get even rougher... almost like a Great Lake. I once watched a fairly large (~80' ?) boat that looked like a tug boat (but was probably a commercial fishing boat) getting pounded by big waves off Gimili.
Even if you do pull your boat out regularly, yes having a screw in hydro anchor would give you some piece of mind. BTW, I guess I can call it a "hydro" anchor now that we're both locals

. As for where to get one... I think you'll need to find an "in" with hydro. Maybe if you called them up, they'd tell you if they'd sell you one... or tell you where you might be able to buy one.... or stop in and chat with the line guy next time you see a hydro truck around... maybe if you offered him $40 or so bucks one would magically appear in your yard a day or two later. Ours came from "buddy of a buddy" type of supply line probably involving bottles of rum. They come in different sizes... if I recall right, ours are about 18" or 2' in diameter. Surely you must know someone who works for hydro??
BTW, they are a pain to screw into the bottom. Ours (we put in 2) are in about 5' of water. You put a handle in the eye on top and then twist them in. Problem is reaching in 5' of water. Sure you can swim down, but then you have no power to turn them (turn yourself instead). Way it worked was have 2 guys, one guy standing on the other guys shoulders. Guy on the bottom has feet on the ground, holds breath, stoops and turns in circles. The other guy supplies the weight that allows the other guy to actually get some traction. When he thinks bottom guy has accomplished enough, he allows him up to breath. As you can imagine, it is hilarious.
If you were putting it in shallower water, it'd probably be easier. You'll need to be able to find them again the following spring... we take the floats off ours and let the cables sink to the bottom for the winter.
Anyway, an anchor like this would be handy if you have the boat in on a nice day, and want to run up to the cabin for lunch, etc... but like I said before I still think you'd be wise not even try to over-night it on that water. With how fast a shallow lake like that can kick up there are many nights that appear fine, but then you get a wicked thunderstorm later on. A few times we changed our minds (thought we'd leave boat on the anchor, but then saw a storm coming)... having to out race a thunderstorm/microburst is not good. We're on the east side of a much smaller lake, and even it gets very rough in summer storms.
Good luck!