ABSTRACT
Deterioration of water quality is not a new problem. To some extent it has existed ever since people began to congregate in cities. But man's impacts on the water environment and on water quality were quite localized and limited until the industrial revolution. Then, the growing concentration of both factories and people gave new dimensions to water quality problems, first in Europe and later in the United States. In recent decades, with the increasingly rapid growth of the economy, the problem has become so large and complex that water quality management must be regarded as a modern problem calling for new approaches.
