I have one but I admit, I haven't filled it with ice, and I'm not sure why you'd want to. But I have been caught in a couple of serious downpours and nothing in the bag has gotten wet at all. The liner on the inside is waterproof, but I don't think the zippers and seams are completely waterproof. So it will probably be fine for heavy rain, but I wouldn't go submerging it under water or anything.