Bay Area Storm Water Authority
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What is non point source pollution?
When it rains or the snow melts, water runs off the land into our streams, rivers, inland lakes and the Great Lakes. As the water moves across various landscapes, such as plowed agricultural fields, city streets and residential backyards. It picks up soil particles, fertilizers, pesticides, animal wastes, road salt, motor oil and other land borne pollutants. This type of pollution from diffuse sources is called nonpoint source pollution.
Nonpoint source pollution is also caused by wind, which, like rain, can pick up soil particles and deposit them in our lakes and streams.
Nonpoint source pollutants include;
nutrients (phosphorus and nitrogen) in fertilizers
pesticides, oil, paint and other household hazardous wastes
fecal coliform bacteria and other pathogens
Just one of these pollutants can have a significant impact on our lakes and streams. For example, one quart of used motor oil can contaminate up to two million gallons of water. Collectively, these pollutants can result in wide-spread water quality problems.
How does it affect the water?
Nutrients from improperly maintained septic tanks and over application of fertilizer can cause algae blooms and other nuisance plant growth. The overgrowth of algae and aquatic plants can limit boating and other water recreation activities.
Oil, grease, paints and pesticides can be toxic to fish and other aquatic life. Soil that is carried off the land by wind and rain settles to the bottom of the stream, river or lake and covers up the gravel and other habitat needed by fish and other aquatic life. Fecal coliform bacteria and other pathogens from livestock manure, pet wastes and improperly maintained septic systems can cause the water to become unsafe for drinking, swimming, boating and other water recreational activities. Leaves and other debris dumped in the water will decompose over time. The decomposition process uses up oxygen in the water – the same oxygen needed by fish and other aquatic life.
Where does nonpoint source pollution come from?
In urban and residential area, nonpoint sources include:
people who over apply pesticides and fertilizers
oil and grease from parking lots
people who dump paint, oil and other substances down the storm drains
soil from alleys and road ditches
soil from constructions sites
people who improperly dispose of leaves and grass
In rural areas, nonpoint sources include:
improperly maintained septic tanks
soil erosion from farm fields and livestock trampling the stream banks
manure from cropland, barnyards or livestock in the stream
What you can do!
Nonpoint source pollution should be a concern of every Michigan resident. Our individual actions do have a significant impact on water quality. You can start today to be a part of the solution to nonpoint source pollution. Here are some things you can do to help:
Apply the proper amount of fertilizer. A soil test will tell you if your lawn needs fertilizer. Call your county Extension Agent for additional information.
Don’t apply fertilizer at times when it might be washed away by rain.
Apply pesticides only when necessary and according to the instructions on the label.
Recycle grass clippings and leaves by mulching or composting.
Dispose of used motor oil and antifreeze at a recycling depository. Check with local services stations for locations of such facilities.
Have your septic system inspected and pumped out every three to five years.
Direct roof runoff into a grassed area. Roof drains should not be connected to a sanitary or storm sewer system.
Seed grass, install sod or plant ground cover to reduce soil erosion
If you notice soil erosion from a construction site, contact the local governing agency responsible for erosion and sediment control.
Fence livestock to prevent access to streams. Stabilize stream banks with vegetation.
Install buffer strips adjacent to all waterways.
Be Active! Join a civic or environmental group and let others know how your feel.