Key
Points
Key Points will give you the main information
you should know to teach the activity.
- When
rainwater falls on the ground, it will often pick
up any pollutants in the environment and carry them
to local bodies of water where they will contaminate
the watersheds.
- Point
source pollution is pollution whose source is easily
identified. This is usually pollution associated with
factories or large farms. For example, if an unusual
chemical is found in a watershed, it could be traced
to a factory on that watershed that makes use of that
chemical.
- Non-point
pollution is pollution whose source cannot be identified.
Fifty percent of all pollution is non-point source
pollution. Non-point pollution often comes from the
everyday actions of regular people and includes things
such as pesticides on lawns or spilled oil from a
car.
- Best
Management Practices are plans on means to reduce
the amount of pollution entering the environment.
Top
Detailed
Information
Detailed Information gives more in-depth background
to increase your own knowledge, in case you want to expand
upon the activity or you are asked detailed questions
by students.
Water
pollution in our watersheds is an issue that affects us
all. It affects us directly through our drinking water
and indirectly through slow changes in the environment.
We have been aware of the problems and solutions for decades.
Industry and individuals have made important changes in
their practices and daily lives but there is still a lot
that can be done.
There
are different types of pollution that affect the water
in our watersheds. One type is categorized as point
source water pollution. Point source water pollution
enters the environment from an identifiable source, such
as from a discharge pipe of a factory. Industries that
have identifiable discharges include sewage livestock
farms, landfills, and water treatment plants. These industries
discharge many different kinds of pollution, ranging from
livestock manure to industrial chemicals.
The
discharge of materials from point sources is regulated
by state and federal government agencies. These industries
are issued a National Pollutant Discharge Elimination
System permit. This means that the pollutants are controlled
and monitored as they are emitted into streams, rivers
and other bodies of water. The emissions must meet the
guidelines of the permits or the facility may be heavily
fined. There are some facilities that do not meet the
guidelines of laws passed by the state and federal governments.
These facilities are not breaking the laws. They have
been “grandfathered” through the laws. Many of these facilities
were operating before the laws were created and are not
able to comply without spending lots of money on refurbishing
major parts of the facility. The companies that run the
facilities would possibly go bankrupt if they were made
to comply with the laws.
Point
sources of pollution, such as the industries mentioned
above, contribute a great amount of pollution to streams,
rivers, and other bodies of water, but they do not contribute
a majority of the pollution. The Environmental Protection
Agency estimated that 50% of the pollution in our nation’s
waters comes from non-point sources. Non-point sources
of pollution are the products of everyday activities by
people like you and me.
Non-point
source pollution is pollution that comes from
sources that cannot be directly located. An example of
non-point pollution is the fertilizer that people put
on their lawns. When excess fertilizer washes off of the
lawn during a rainstorm it can enter the watershed as
runoff. Runoff is water that flows on the surface across
lawns, roads and other landscape features. Pollution can
be carried or dissolved in runoff and enter the watershed.
Once in a body of water, the pollution can be sensed with
the proper equipment, but it can not be directly linked
to any particular lawn in the community. It is pollution
that originated from an indistinguishable (non-point)
source. Runoff originates from urban areas, agriculture
land, construction sites, lawns, and some industries,
such as mining. The main elements of polluted runoff are
heavy metals, salts, sediment, nutrients, and bacteria.
Many
of our daily activities can contribute to non-point source
pollution, including lawn and landscape maintenance; car
maintenance; use of vehicles; and construction of structures,
like homes, highways and shopping malls. In these activities,
we apply fertilizers and pesticides; spill small amounts
of oil and gasoline; and dig up the ground causing soil
erosion. The chemicals and loose soil stay in the area
until there is precipitation. The water from a rainstorm
falls in these areas, picks up the pollution, and then
flows towards storm drains and streams and rivers.
When
the rainwater goes directly into a stream it carries all
of the pollution with it. Storm drains, though, are not
always a better destination for the rainwater. Many towns’
storm drains and water treatment systems are unable to
cope with the high volume of water that runs through them
during a storm. When this happens the runoff is diverted
directly into the watershed. The runoff contains heavy
metal, salts, oils and soil, sometimes in high concentrations.
These types of events have been called “shock
loadings.” Shock loadings can temporarily make
the water unfit for life. In many communities, beaches
are closed to recreational activities immediately after
a rainstorm. The runoff from the storm carries too much
pollution into the water for it to be safe to swim.
What
can we do? Point source water pollution is under strict
regulations, so we are already helping the environment
by restricting how industries pollute water environments.
We cannot entirely eliminate pollution from industries
because we need them to support our way of life. But we
can still develop new and better methods of reducing industry’s
waste.
There
are many things that we can do to help reduce non-point
source water pollution. As people participate in a variety
of activities, they contribute little bits of non-point
source pollution. Each person or activity is not contributing
dangerous levels, but all of the little bits added together
can be damaging to the environment, wildlife and people.
The key to lessening non-point source pollution is education.
If everyone understands how their activities contribute
to pollution, maybe they can make small changes in their
activities that will help reduce their own pollution contribution.
Examples include using a little less fertilizer on their
lawn and reducing the amount of oil they spill when working
on their cars.
Towns
and cities can reduce the amount of non-point source pollution
by increasing the frequency of street cleaning, encouraging
people to take mass transit, enforcing stricter regulations
concerning construction site runoff and use of fertilizers
and pesticides. Towns and cities review potential pollution
sources in their area and generate Best
Management Practices (BMP’s) to deal with them.
Examples of BMP’s include planting buffer zones of vegetation
in certain areas. The buffer zones absorb runoff and allow
it to be slowly emitted after the rainstorm, preventing
some of the shock loading of watersheds.
Point
source and non-point source water pollution can be reduced
if people and community leaders have the information they
need. Taking care of the water in our watersheds is a
responsibility we all must share. We are all a part of
the problem and we can all be a part of the solution.
Point
Source And Non-point Source Water Pollution
Common
types and sources of point source (ps) and non-point source
(nps) water pollution. Also included is information about
how the pollution enters the watershed (runoff, ground
water, or direct) and what some Best Management Practices
(BMP’s) are that may help reduce the amount or affect
of the pollution from these sources.
| Type of pollution |
point (ps) or non-point (nps) |
Source |
Best Management Plans (BMP) |
| salts |
nps |
salting icy roads |
careful use |
| pesticides, fertilizers |
nps |
lawn care |
careful use |
| pesticides and fertilizers |
nps |
golf courses |
careful use |
| pesticides |
nps |
agriculture pesticides |
buffer zone or collection pool |
| oils, gasoline |
nps |
recreational activities |
careful use |
| oils, gasoline |
nps |
long commutes/ excess driving |
car pooling, mass transit |
| oils, gasoline |
nps |
car maintenance |
careful use |
| oils, gasoline |
nps |
paved roads |
porous roads |
| nutrients and bacteria |
nps |
agriculture fertilizers/manure |
buffer zone or collection pool |
| nutrients and bacteria |
nps |
septic systems |
better containment |
| hazardous chemicals |
nps |
households |
careful use |
| eroded soil, heavy metals |
nps |
mining |
better containment |
| eroded soil |
nps |
construction runoff |
better containment |
| chlorine, heavy metals |
ps |
Industrial facilities |
careful use |
| chlorine |
ps |
sewage treatment plants |
careful use |