You will require this registration if you intend to deliver water with a water transport vehicle to the public for human consumption.
A water transport vehicle is a vehicle from which water is transported, sold or handled with the intention of selling. Water intended for human consumption includes water used in the preparation of food or ice, or to preserve unpackaged food.
You will only need to register with the council in which your vehicle is garaged (principal council), regardless of where you deliver the water. If you operate more than one vehicle, then you need to register with the council in which the majority of vehicles are garaged.