Stormwater Pollution Sources

A lot of the pollution in our rivers starts out in our yards and driveways. All over the city, small volumes of pollution produced from everyday activities are conveyed to our streams and rivers by runoff. You might be surprised to learn where pollutants that affect stormwater and runoff come from. You might think, for example, that swimming pool water is fairly pure. But it contains chemicals, such as chlorine, that can be harmful.

Although we don’t cover every source of stormwater and runoff pollution here, we have tried to discuss the most common ones. See below for more information about sources of pollution. There are many simple steps that can be done to reduce the impact to our environment.

Car Washing

Washing your care on your paved driveway can send detergent, grease and other pollutants into storm drains and directly into waterways without treatment.

If you wash your car at home instead of at a car wash, it’s best to use a spray gun and wash the car on grass or gravel to reduce runoff into storm drains. Grass and gravel surfaces absorb water. When you’re through, empty any buckets you’ve used into a sink, toilet or floor drain so the water will be treated by the municipal water treatment facility.

Motor Oil

Used motor oil is the most significant source of oil pollution in our waterways. Just one pint can create an oil slick covering about an acre of water. This oil contains pollutants that can affect wildlife and vegetation as well as damage drinking water.

The best way to deal with used motor oil from any source, such as cars, boats, lawn mowers and others, is to recycle it. For recycling information, call the Johnson County Environmental Department’s Household Hazardous Materials Program, (913) 715-6900. You can also visit to search for collection centers by your zip code.

For more information about used motor oil and motor oil recycling, visit:

Parking Lots

Too often, parking lots become trash receptacles. When it rains or the parking lots are swept and washed the trash goes down storm drains and ends up in our waterways.

To help prevent pollution from parking lots:

  • Put your trash in a proper receptacle
  • Service your car to prevent fluid leaks

If you have a parking lot:

  • Sweep at least once a week
  • Put up signs to remind people to dispose of waste properly
  • Clean up auto fluid spills immediately
  • Pick up debris every day
  • Keep trash receptacles conveniently located and empty them often

For more information about preventing stormwater and runoff pollution from parking lots visit KCARE/Kansas State University

Pet Waste

You contribute to a major source of water pollution in your community when you leave your pet’s feces lying on the grass or pavement. Pet waste washed into storm drains goes directly into our rivers, streams and lakes, untreated.

Be a good neighbor and pet owner. Pick up your pet’s waste and dispose of it by flushing it down the toilet, putting it in the trash or burying it.

For more information on preventing pollution from pet waste visit KCARE/Kansas State University.


You might not think of sand, clay and soil particles as pollutants, but when they get into our rivers and streams, they become sediment. The Environmental Protection Agency lists sediment as the most common pollutant in our waterways.

You can help prevent sediment from filling our rivers and streams by:

  • Preventing sediment runoff from construction sites
  • Sweeping rather than washing sidewalks and driveways
  • Using mulch or straw to cover reseeded areas
  • Using compost or mulch in your garden
  • Washing your car on grass instead of pavement

For more information about sediment, visit:

Lawn Chemicals

Improper application of lawn fertilizer, herbicides and pesticides can result in drinking water pollution and harm to plants, animals, insects and fish. Some of these chemicals also can be absorbed through the skin, inhaled and swallowed.

You can reduce pollution from lawn chemicals by:

  • Testing your soil before applying chemicals
  • Using products properly
  • Not using chemicals if heavy rain is predicted
  • Landscaping with native plants
  • Using organic fertilizer

For more information about lawn chemicals and water pollution visit KCARE/Kansas State University.

Swimming Pools, Hot Tubs, & Spas

Draining swimming pools, hot tubs and spas without adequate attention to the chemicals they contain can contribute to waterway and soil pollution. If the runoff is uncontrolled or misdirected, the water can wash pollutants into storm drains or cause damage to neighbors’ property.

Fortunately, chlorine can be removed simply by allowing the water to be exposed to sunlight for a sufficient amount of time. By paying attention to drainage design, you can prevent damage to your neighbors’ property.

For more information about draining swimming pools, hot tubs and spas, visit Johnson County Pool Water Disposal.

Sump Pumps & Roof Drains

Sump pumps and roof drains carry water away from buildings. The water usually comes from rain or snow does not pass through the sanitary sewer. So it’s untreated runoff and can be a source of waterway and soil pollution.

It’s important to make sure roof drain and sump drainage is carefully planned when your system is installed. The water should be diverted so it does not cause damage to neighbors’ property or carry pollutants into storm drains. Drainage planning can help prevent problems and conserve water through use of rain gardens or other methods.

For more information about sump pumps and roof drains, visit Leawood Development Ordinance.