Comprehensive assessment of the freshwater resources of the world Water futures: assessment of long-range patterns and problems

Abstract

Few would dispute that urban water systems should be both healthy and sustainable. Ideally, along with efficiency, these are central pillars in every urban water strategy. Unfortunately, the narrow pursuit of health can undermine the sustainability of water systems, and vice versa. Such trade-offs must not be rationalised away, but recognised in order to develop diversified and better aimed water strategies. It is crude policies, such as promoting health by providing free water for all, or promoting sustainability by charging everyone high prices, that create the steepest trade-offs. Trade-offs are far less evident with more sophisticated policies, targeting particular users or uses, and built upon a better understanding of water related disease, hydrology, markets and politics. Our ignorance is however no excuse for inaction: there are many obvious things that need to be done. But nor is the need for action an excuse for remaining ignorant: there remains a great deal of relevance to learn regarding urban water, and how it relates to both health and sustainability.