Biological Characteristics of Water
The biological characteristics of a water body refer to
a variety of living organisms that can be found in water. These
include microscopic viruses, bacteria and protozoans; as well as
phytoplankton (microscopic algae), zooplankton (tiny water animals),
insects, worms, large plants and fish. Of significance to humans
is that disease-causing viruses and bacteria can be present and
transported in water. Many of these pathogens can enter the water
system in sewage (human and animal waste).
Scientists have devised a method of determining if water has been contaminated with sewage by identifying and measuring certain bacteria called fecal coliforms. These bacteria are known to live in the intestines of mammals. Although not dangerous in themselves, the presence of fecal coliforms in water indicates that sewage is present and that other disease causing organisms may also be in the water.