are three types of water contamination. These include agricultrual , industrial , and municipal contamination. For
the purposes of this website, oil spills will be separated from the industrial category and placed into their own
category. This will make four cateories of water contamiation: agricultural, municipal, industrial, and oil
Agricultural contamination refers to
the contaminants found in the surface water and/or groundwater as a result of large-scale livestock and poultry farming
as well as from farmers' croplands. A classic example of agricultural contamination is pesticides being washed into
rivers and streams by rainfall.
Most agricultural contaminants that
enter the groundwater are nitrates and pesticides. Pesticides, designed to protect the farmer's crops from
pesky insects, are applied directly to the soil by the farmers. However, if these pesticides are not applied in
the proper conditions or if the field is improperly managed, the pesticides leach through the soil and into the groundwater.
Contamination due to pesticides, although found in almost every American state, occurs much less frequently than nitrate
contamination. Nitrate contamination is much more common because it is very soluble in water. This means that
it can leach through wet or moist soil and into the groundwater very easily.
that are causing the contamination can come from a number of sources such as: nitrogen rich fertilizers, animal manure,
and nitrogen-fixing plants such as legumes. There are certain conditions that will be more likely to cause
a contamination than others. The most common contamination-causing conditions are: improper timing of application
of fertilizer or manure, excessive fertilizer or manure, and over irrigation.
|This is a picture of a farmer spraying his crops with pesticides
refers to the wastewater that comes from our homes and small businesses. Due to advanced filtration systems, many
of the contaminants are filtered out or broken down before the water is returned to the drinking water supply.
However, these barriers do not stop everything. Sometimes, a contaminant survives the filtration system and appears
in the drinking water. This contaminant could have originated from almost anywhere. Take a minute to consider
what kinds of things you dump down your sink on a daily basis.
A good example
of a municipal contamination would be Lake Huron. Recently, several beaches on Lake Huron were closed due to E.
coli contamination. E. coli is a bacteria that is found in the stomach and intestines of humans and cattle.
When it is found on a beach, that is a good indication that somehow, fecal matter has found its way into the lake water, which
raises serious health concerns. If people were to drink the water containing the e. coli, they would become very
sick and could possibly die.
of e. coli contamination was demonstrated in Walkerton, Ontario in May 2000. Filtration of the town's
drinking water was improperly managed and as a result, e. coli made its way into the drinking water. When people
drank their tap water as they usually did, they were unknowingly ingesting e. coli bacteria. By the time it was over,
seven people had died and over 2,000 people were sick. This clearly demonstrates what can happen when the filtration
process is neglected. The best defence against municipal contamination is an up-to-date, carefully monitored water
|Water Treatment Facility
|This is a picture of a water treatment facility. Here, water is filtered to eliminate contaminants.