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Table 2. Major categories of water pollutants, their sources, effects and control
CATEGORY
A. Health Problems
1.Infectious agents /Disease producing organisms
2. Organic chemicals
3. Inorganic chemicals
4. Radioactive materials
B. Ecosystem Disruption
1. Sediment
EXAMPLE
 Bacteria, viruses, parasites
 Pesticides,
plastics, detergents,
oil, and gasoline
 Acids, caustics, salt, metals
 Uranium, thorium, cesium, iodine,
radon
 Soil, silt
SOURCES
EFFECTS
 Human excreta, Animal wastes Contaminated
aquatic foods (clams, oysters)
 Industrial and farm use.
 High incidence of water borne diseases
such as cholera, typhoid fever, dysentery,
polio, infectious hepatitis, fever, nausea,
and diarrhea.
 Industrial effluents, household cleansers,
surface runoff.
 Mining and processing of ores, power plants,
weapons production, natural sources.
 Land erosion
 Soil Erosion from farPmland strip mined land,
logged off areas,
and Construction site
(roads, homes, and airports)
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2. Plant Nutrients
3.
Oxygen-demanding wastes
4. Thermal
CONTROL
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Reduce runoff from backyards and feeblest
More effective sewage treatment.
Proper disinfection of drinking water.
Proper waste management
Fills in reservoir. Clogs irrigation canals
Increases probability of floods.
Impedes progress of barges.
Interferes with photosynthesis, therefore,
DO is reduced.
Destroys freshwater mussels (clams).
Fish die from asphyxiation.
Destroy spawning sites of game fish.
Necessitates expensive filtration of
drinking water.
 Employ erosion control practices on farms such
as contour plowing, cover cropping and shelter
belting.
 Employ erosion control practices at construction
sites: sodding, use of catch basins, etc.
 Use mulching and jute matting on seeded road
banks.
 Establish temporary cover, such as rye and millet,
at construction sites.
Euthrophication .
May cause methemoglobinemia in infants.
Foul odors.
Decreased recreational and aesthetic
values.
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 Nitrates, phosphate
 Plant and animal manure and
residues
 Heat
 Agricultural and urban fertilizers, sewage,
manure.
 Soil erosion. Food processing industries.
 Runoff from barnyard, feedlots, and farmlands.
Untreated
sewage.
Industrial
wastes.
Household detergents. Exhaust of motor cars.
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 Sewage, agricultural runoff, paper mills, food
processing. Soil erosion. Leaf fall.
 Fish kills. Human sewage. Domestic garbage.
Remains of plants and animals.
 Runoff from urban areas during storms.
 Industrial wastes (slaughterhouses, canneries,
cheese factories, distilleries, creameries, and oil
refineries.
 Bacteria that decompose the organic matter
will deplete the stream of oxygen.
 Game fish are replaced by trash fish
Valuable food for game fish (may flies,
etc) is destroyed.
 Foul odors.
 Power plants, industrial cooling
 Mid summer heating of shallow water by the
sun.
 Discharge of warm water from electrical
power, steel, and chemical plants.
 Disrupt structure of aquatic ecosystem.
 Causes shift from desirable to undesirable
species of algae and fish.
 Kills cold water fish such as salmon and
trout.
 Blocks spawning migrations of salmon.
 Interferes with fish reproduction.
 Increases susceptibility of fish to disease
and to the toxic effects of heavy metals
such as zinc and copper.
Tertiary sewage treatment.
Reduce of commercial fertilizers.
Change detergent formula.
Control soil erosion with strip cropping, contour
plowing, and cover cropping.
 Control feedlot runoff with catch basins.
 Reduce runoff from barnyards.
 Reduce ROD of sewage with modern secondary
sewage treatment plants.
 Reduce runoff from feedlots with catch basins.
 Reduce the nation’s energy demands for
electricity.
 Use closed cooling systems exclusively.
 Instead of discharging heated water to streams,
use it to heat homes, extend growing seasons on
cropland, increase growth rate of food fish and
lobsters, and prevent host damage to orchards.