• Water quality management is concerned with the control of
pollution from human activity so that the water is not
degraded to the point it is no longer suitable for intended
• Water quality management is also the science of knowing
how much is too much for a particular water body.
• Water is typically referred to as polluted when it is impaired
by anthropogenic contaminants and either does not support
a human use, like serving as drinking water, or undergoes a
marked shift in its ability to support its constituent biotic
communities, such as fish.
WATER POLLUTION CATEGORIES
• Surface water
– Point source pollution: It refers to contaminants that enter a
waterway through a discrete conveyance, such as a pipe or
ditch. For example; discharges from a sewage treatment
plant, a factory, or a city storm drain (domestic sewages,
industrial wastes, municipal sewage).
– Non-point source pollution: It refers to diffuse contamination
that does not originate from a single discrete source. It has
multiple discharge points. For example; contaminated
stormwater washed off of parking lots, roads and highways
• Ground water
– Groundwater pollution is often caused by pesticide
contamination from the soil, this can infect our drinking water
and cause huge problems.
• Includes viruses, bacteria and protozoa excreted by
diseased persons or animals;
• When discharged into surface water they make the water
non-potable, i.e., unfit for drinking;
• If concentration of pathogens is sufficiently high water may
also be unsafe for swimming and fishing;
• Certain shellfish can be toxic because they concentrate
pathogenic organisms into their tissues making the toxicity
levels in the shellfish much greater than the levels in the
OXYGEN DEMANDING WASTES
• Anything that can be oxidized in the receiving water
with the consumption of dissolved molecular oxygen
is termed as oxygen demanding...