Chapter 21 water pollution
Water pollution – any chemical, biological, or physical
change in water quality that has a harmful effect on
organisms or makes it unsuitable for use.
Point source – specific locations through pipes, ditches or
sewer lines
Ex. Factories, sewage treatment, oil tankers
Easy to identify monitor and regulate
Nonpoint source – scattered and cannot be traced to a
single source of discharge.
Ex. acid deposition, runoff of chemicals, and sediment.
Difficult and expense to identify. Major sources are
agriculture, industries, and mining.
Major pollutants and effects
Soil erosion disrupts photosynthesis and smothers
aquatic organisms
Nutrient imput from sewage, animal wastes or fertilizers –
excessive algal growth cultural eutrophication – reduces
oxygen D.O. in water. Infectious diseases.
Runoff or point pollution from industries, households and
farms – toxic chemicals such as oils, solvents, pesticides,
acids, metal and plastics kills organisms.
Heat from electric power and industrial plants
reduces D.O.
-
Two major water pollution problems
1) exposure to infectious diseases organisms from
contaminated drinking water
2) not having enough water for effective sanitation.
- 500 types of disease causing organisms that can come
from water contaminated from human or animal waste
Disease
Amoebic dysentery
Cholera
Cryptosporidium
Enteritis
Giardiasis
Infectious hepatitis
Schistosomiasis
Organism
Effect
Typhoid fever
Fecal coliform bacteria measurements are a common way
to measure water contaminated with fecal waste. (coliform
is found in animal intestines – not diseases causing)