Impervious Surfaces

Impervious surfaces include any surface that does not allow water to soak into the ground, such as buildings, driveways, sidewalks, and roads. Instead, water runs off the hard surfaces into a storm drain that leads to a lake or stream. Rain or snowmelt can wash away materials on impervious surfaces, such as fertilizer, grass clippings, oil, gasoline, and trash. In the water, these items become water pollution. You can do several simple things to manage your impervious surfaces to reduce the potential for water pollution. They include:

  • NEVER dump anything into a storm drain. Not only is that pollution, but it’s also illegal. Only rain down the drain!
  • Know where storm drains are located in your neighborhood. Check them periodically and remove debris from the inlets. This will prevent debris from becoming water pollution and reduce the chance of flooding during a rain or snowmelt event.
  • Have a spill kit handy to immediately clean up spills in your driveway, such as oil or gasoline leaks from cars or lawn mowers. A spill kit should include gloves for personal protection, absorbent material (such as kitty litter), a broom and dust pan, and garbage bags. NEVER wash anything off the driveway with a garden hose.swstormdrainclippings2.jpg
  • Sweep or blow grass clippings back into the lawn. Grass clippings contain nutrients, so they will do more good in the lawn than in the water! The same applies to fertilizers.
  • Wash your car in the grass where water can soak into the ground or take it to a commercial car wash. Commercial car wash water goes to the wastewater treatment plant in the sanitary sewer system.
  • Pick up and properly dispose of pet waste. Pet waste contains both nutrients and bacteria that rain can wash away into our water. Yuck!
  • Reduce the amount of rainwater that runs off your property by installing a rain barrel. Rain barrels capture runoff from your roof and store it for later irrigation or slow release. Alternatively, direct your gutter downspouts into landscape beds or the lawn to keep stormwater out of storm drains.