Air quality canister filled with water

What is your question?

My mechanic tells me that my canister cover has a leak and is filling up with water. I have ordered parts to repair it but it's been 3 weeks now and I've been told not to drive the car when there is water on the road. It's winter here (and roads are wet also) - what happens if the canister has water in it that freezes? Will my car stop working? Will my fuel tank collapse?