All life on this planet is supported by a fixed quantity of water. We use the same water over and over again, the same water which our grandparents used for brick-making, the same water in which Shakespeare washed his feet, the same water in which Moses floated in a basket through the bulrushes, the same water the ancient Romans transported through their aqueducts to support life in their city. In fact, the water that you used to brush your teeth this morning is over four billion years old. So have a little respect.

    Of all water on our planet Earth, 97% is salt water. Only 3% is fresh water, and most of that is frozen in the polar ice caps.

    Less than 1% of Earth's water is available for our use.

We can't make new water, any more than we can make new land. If we misuse the water we have, we can't send out for some fresh stuff. Water comes out of the tap in unlimited quantities whenever we want it. We generally assume that we have vast reserves of water available. And we generally assume that it's free, or almost free. But before clean water comes out of our taps, several things have to happen. We have to find a source of water, build machinery to pump it, piping to carry it, plants to treat it, Thanks to our treatment of water, chlorine has become an acquired taste in millions of households. We have to elect politicians who will run our municipal affairs, and look after our water treatment, and do the paperwork involved in supplying us with water. Once we get the water to our houses, we have to install pipes and valves and shut-offs and vents. We have to put in a separate Once we've got water, what do we do with it? We put it through our washing machines, toilets, sinks, dish- washers, car washes and pesticide-filled lawns. We use it to wash our windows, our sidewalks and streets. We spray it in the air for pretty fountains. We put out fires with it. We clan wounds with it. We make concrete with it. We use it in the production of plastics, steel and paper. We hose down chemical spills and industrial work sites with it. We clean paintbrushes in it. And we drink it.

    What if we had water meters beside our kitchen sink? What if they read dollars and cents instead of gallons or liters?

Then we have to deal with getting rid of it. We need to build another whole network of drains to carry away our dirty water and sewage. We need to build treatment plants, and hire people to run them. And we need to elect politicians who will vow to "do something" to clean up the water that we've polluted. The process costs billions of dollars worldwide, and still people suffer and die in many parts of the world for want of clean water, while we blithely open our taps and let our most precious resource pour down the drain. There's not much we can do at home about the un-equal distribution of water in the world. But the other major problems, contamination and waste, we can do something about. Although most of the advice in this article has to do with waste (we'll deal with contamination in other chapters), these two problems are connected in ways that might not be obvious. The more we process our water, the more chance it has to become contaminated. That's because we have one sewage system for all purposes. We put our drinking water, our toilet waste and commercially contaminated waters all down the same system. We do our best to clean it up, then we pour it all out into the same river, lake on stream, and then we drink it again. And of course, the more water we have to process, the more bleach we have to produce (which isn't a terrific thing to have around-it is, after all, a poison), and, naturally, the more we have to pay our governments for looking after all this stuff for us. So it's not so easy to keep cleaning our water. Yes, we could be drinking Shakespeare's bathwater, but more to the point, will our great grandchildren be able to drink the water we used to hose down the dog? Will there be any clean water left? Does it make any sense for us to save water at home? Isn't our home usage just a drop in the bucket, compared to what agriculture and industry use?

    Household usage is about 5% to 10% of total fresh water used worldwide. Most of that is used in North America.