1.1 INTRODUCTION

Did you know that there are almost 6 billion people in the world?

The world s population exploded during the twentieth century. At the close of 1998 approximately 5.9 billion inhabitants could call the planet Earth home, up from 4 billion in 1975. That such growth could occur is a testament to our unique ability to provide the essentials of clean air, water, food, and health care to our masses. However, during the latter half of the same century, people also recognized that the world s resources could not continue to sustain this rate of growth indefinitely at least, not if we continue to use the same methods to which we have become accustomed. Our resources are finite. Although efforts are under way to control population growth, similar efforts exist, and are being refined, to ensure that our most vital resources are used wisely to sustain the world s population which will continue to grow even if we succeed in slowing the rate of growth.

The availability of safe water has been a major contributing factor in the growth of the world s population, by serving our drinking water and sanitation needs. The ability to create large water supply systems to abstract or withdraw, treat and transport vital water to whole communities stands as one of history s great engineering marvels. Yet notable caveats exist to this success story. Many developing countries still do not have the water supply infrastructure to provide clean water to individual customers, or to supply...