There are two issues, the consumption versus withdrawal. Generally speaking, you withdraw water, a small amount is consumed, and the rest goes back to the environment. In the case of a municipality, normally you'll consume about 10% of what you withdraw. In thermal power, you might only consume 1% of what you withdraw. In agriculture it might vary from 20% to 80% of what you withdraw. So it depends on the use and so on.
In terms of the question of water as a commodity and so on, and water rights, what happens in Canada is that you have two different systems for managing water use. In the parts of the country such as Ontario, Quebec, and the east, where you have a lot of water, we consume less than 1% of the water that's available. So we don't need a system of water rights and a system where we can buy and sell water. There's lots of water. In those provinces we generally have a licensing system. We license water use so that we make sure this water use is not going to interfere with the environment and other things. In Quebec, Ontario, and the Maritimes and so on, we license water use.
In the west, where you actually have a water shortage in the Palliser Triangle and other places, you don't have enough water for the uses that you want to use, we have something called a water rights system. People are issued a right to use water. In the extreme now, for instance in Alberta, they've now introduced legislation whereby a person can get a right from the government and sell it to somebody else. So you're actually into a situation now in parts of the country that are water short where you can actually obtain a right to use water and you can actually sell it.
So the situations are very different where you have lots of water and where you don't have lots of water, and the legal systems are adapted to take that into account.