Simply put, water is a precious quantity. We depend on water to grow crops, raise livestock, produce electricity, manufacture an enormous variety of products, and most importantly sustain life. Unfortunately this precious quantity is becoming increasingly scarce due to the demands of society. While people living in rural areas do not have much difficulty in finding the water they need, large city populations find this challenge much more daunting. Most large cities have already exploited all the nearby water resources and are forced to expand their search for water, often at a great expense. According to a report from the United Nations in 1989, half of the total population in the world will be living in cities by the year 2000. Additionally, the number of cities exceeding 1 million residents is expected to be over 400 by the end of this century. (EPA, 1992). This is a trend that is especially true in the United States. Already in 1966, the U.S. Census Bureau estimated that two thirds of the U.S. population lived in urban areas and of the remaining one third, only 8% truly lived in a rural setting (Wright, 1966). Thus, the search for suitable water effects the majority of us.