Science of Water : Concepts and Applications

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Water Biology
Scientists picture the primordial Earth as a planet washed by a hot sea and bathed in an atmosphere
containing water vapor, ammonia, methane and hydrogen. Testing this theory, Stanley Miller at the
University of Chicago duplicated these conditions in the laboratory. He distilled seawater in a special
apparatus, passed the vapor with ammonia, methane and hydrogen through an electrical discharge at
frequent intervals, and condensed the “rain” to return to the boiling seawater. Within a week, the seawater
had turned red. Analysis showed that it contained amino acids, which are the building blocks of
protein substances.
Whether this is what really happened early in the Earth’s history is not important; the experiment
demonstrated that the basic ingredients of life could have been made in some such fashion, setting the
stage for life to come into existence in the sea. The saline fl uids in most living things may be an inheritance
from such early beginnings.
—F.N. Kemmer (1979)
Because microorganisms are signifi cant in water, in disease transmission they are the primary
agents of water treatment processes. Water practitioners must have considerable knowledge
of the biological characteristics of water. Simply put, waterworks operators and students of the
science of water cannot fully comprehend the principles of effective water treatment and water
science without knowing the fundamentals concerning microorganisms and their relationships to
one another; their effect on the treatment process; and their impact on consumers, animals, and
the environment.
Water practitioners must know what principal groups of microorganisms are typically found
in water supplies (surface and groundwater). They must be able to identify those microorganisms
that must be treated (pathogenic organisms) and removed or controlled for biological treatment
processes. They must be able to identify the organisms used as indicators of pollution/contamination
and know their signifi cance, and they must know the methods used to enumerate the indicator
organisms. Finally, water treatment operators must be familiar with those organisms that indicate
process conditions to optimize process operation.
√ Important Point: To have microbiological activity the body of water or wastewater must possess
the appropriate environmental conditions. The majority of wastewater treatment processes,
for example, are designed to operate using an aerobic process. The conditions required for
aerobic operation are (1) suffi cient free, elemental oxygen; (2) suffi cient organic matter (food);
(3) suffi cient water; (4) enough nitrogen and phosphorus (nutrients) to permit oxidation of the
available carbon materials; (5) proper pH (6.5–9.0); and (6) lack of toxic materials.
BIOLOGY/MICROBIOLOGY: WHAT IS IT?
Biology is generally defi ned as the study of living organisms (i.e., the study of life). Microbiology is
a branch of biology that deals with the study of microorganisms that are so small in size that they
must be studied under a microscope. Microorganisms of interest to the water practitioners and students
of the science of water include bacteria, protozoa, viruses, algae, and others.
√ Note: The science and study of bacteria is known as bacteriology.
As mentioned, the waterworks operator’s primary concern is how to control microorganisms that
cause waterborne diseases—waterborne pathogens—to protect the consumer (human and animal).
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