Back in the day when I did A LOT of cold camping in the BWCA- for water we just drank it straight from a properly placed auger hole over deep water. Most nights- too shot for even a fire so any boiling was not an option. Just a warm drink with your meal from the stove was the only warm drink you got until breakfast. But I do agree- after 3, maybe 4 nights cold camping some form of drying heat is needed. At that's why my group got out of dodge after that time frame! IMO-- you should be OK drinking from the lake straight with common sense but if your going to have a fire might as well boil.
The two loudest sounds known to man: a gun that goes bang when it is supposed to go click and a gun that goes click when it is supposed to go bang.