From space, the Earth appears blue. It is the water planet. But, only a tiny fraction (less than 3%) of Earth is water is fresh. Mostly it is salty from the sea. A huge amount of Earth's finite fresh water resource (97%) is locked up, most in the frozen Antarctica or deep underground beyond the easy reach of man. Worse, careless actions by individuals have polluted much of the finite fresh water accessible to mankind. Thus like Coleridge's Ancient Mariner, the Earth is awash in water with much of it unfit to drink.
Before the agricultural and industrial revolutions, less than one billion people competed for available fresh water. Despite occasional site specific droughts, fresh water shortages were the exception rather than the rule. Today, as we approach the 21 century, there are six billion individuals competing for their share of the finite water resource. And projections are for at least eight or possibly more than ten billion by 2050. Yet the total quantity of water on Earth remains relatively constant.
More people means more fresh water demand. It may be useful to remind ourselves of some of the multiple uses of our fresh water resources. They include drinking, cooking, cleaning, industrial production, irrigation, fisheries, aquaculture, recreation, transportation, power generation, aesthetics and even putting out fires. Agriculture, which already accounts for over two-thirds of all human water use, will need more to grow food. Industry, currently accounting for only twenty percent of water consumed, is expected to expand its output four- or five-fold before 2050, thereby increasing its water requirements.
Industry uses water as a basic component of many products desired by humans. Water has traditionally been a convenient and cost-effective means of removing wastes and by-products from manufacturing processes. Water for most of industry is a relatively minor cost of conducting business. Now all this is changing. Those billions of additional people will need more water to drink, wash and cook. They will also need more food, goods and services, all of which require water. As a result, in certain locations, water for industrial expansion may not be available at any price. But in addition there may not be adequate fresh water to meet the crucial needs of natural ecosystems, to maintain wetlands, for lakes and streams to provide recreation and fishing, and to replenish underground aquifers.
A number of regions are already suffering fresh water shortages. As populations increase and living standards rise in the first half of the 21 century, more regions will suffer increased water stress. The world is not running out of fresh water; but it is not distributed equally and, too often, it is not where it is needed. All users, individuals, farmers and industry should take action to protect and use water more efficiently and more sustainably.
Industry could be at risk when fresh water shortages occur. Highest priority for scarce fresh water is given to domestic needs and then to farmers to grow food. Water for industry is often given relatively lower priority. Water for the natural environment, too, is often ignored. The fact that industry might be willing to pay more for water may be irrelevant and water for industry may not be available at any price. Water would then become a limiting factor for sustainable development and future industrialization in water scarce regions.