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This series deals with methods of ensuring supplies of pure water to
areas which have polluted water. Criteria for purity and pollution vary
with the intended use of the water, b u t there is no question t h a t in the
recent past water pollution has become worse while, on the other hand,
purity requirements for several important uses have become more stringent.
Hence the need for action on a national level has been recognized in m a n y
countries.
I n the United States, the 1972 Amendments to the Federal Water
Pollution Control Act made water pollution control an important and
permanent governmental requirement. Waste water discharged into a city
sewer or into a receiving water body must be adequately treated. T h e
requirements are specified in detail in the Act; industries and municipalities
are now in the process of taking corrective actions which are often quite
expensive. Similar laws are either in preparation or already on the books in
other countries.
T h e series as a whole addresses itself to water supply planners who wish
to have on their shelves a comprehensive and practical multivolume manual
on water pollution problems. While the solution of any water pollution
problem must in general be tailored to the specific situation in which t h e
problem arises, much can be learned from the experience of others who
have already solved similar problems, or at least developed technical
methods for solutions. A number of good books on water pollution subjects
have been available in the past, b u t now t h a t the technology and legislation
are beginning to change rapidly, it is necessary t h a t the workers in this field
have at their disposal a series of volumes covering the most current state of
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