Reduce Stormwater Runoff

Managing stormwater is an important part of water quality protection since water flowing across the land can transport debris and pollution into our waterways. Hard surfaces like rooftops, sidewalks, driveways and parking lots generate large quantities of stormwater every time it rains. Rainfall and snowmelt carry oils, sediments and other polltants into the curb and stormwater system, untreated, to nearby water ways.

What You Can Do to Reduce Stormwater Runoff

Pave Less and Landscape More
Pave only the area needed on your property. Landscaped areas absorb water and generate less water runoff than hard-surface areas. Green space also provides a natural pollution-filtering system. Better yet, pave with pervious surface.

Pave with Pervious Surface
Pervious pavement slows down, soaks in & cleans up stormwater naturally. Many alternatives provide a hard surface while allowing water to filter through and reach the underlying soil. Benefits include: improves water quality, melts snow and drains faster, recharges groundwater, reduces heat island effect, lessens downstream flooding and stream bank erosion.

Plant a Rain Garden
Rain gardens add beauty and reduce the amount of stormwater entering the rivers. Deep rooted, native plants arranged in a bowl-shaped garden slow and filter rainwater before it enters streams and rivers. View a Guide to Planning & Installing a Rain Garden(PDF, 1MB).

Plan a Green Roof
A green roof provides an alternative to traditional asphalt, tile or shingle rooftops. Engineered to keep the roof water-tight and provide an environment for plants to thrive, green roofs recreate lost green space at the roof level. They act like a sponge absorbing rain water, slowing down and releasing cleaner runoff. Besides protecting water quality, green roofs have the added benefit of reducing energy costs by providing another layer of insulation.

American Rivers recently launched its "Green to Earn Green," a tool that helps users design a green roof using Google Maps. Users can simply type in their address, find their roof, and select the surface area to green. The tool automatically calculates the money saved and runoff prevented with the user’s green roof design.

Plant Trees & Shrubs
The roots hold water in the ground, slowing runoff and reducing soil erosion. Trees can lower air conditioning costs too!

Collect Rainwater for Future Use
Catch spring and summer showers in a rain barrel to water plants on dry summer days. Use soaker hoses or drip irrigation in flower and vegetable gardens to allow for deep, infrequent watering. If you use sprinklers, direct them away from pavement.

If Your Home Has a Drainage Ditch or Swale, Do Not Fill It In
Do not build anything over it and please keep it free of litter.

Wash Your Car Responsibly
If washing at home, do so over gravel or in the yard to avoid soapy runoff from entering the storm drains. Better yet, go to a commercial car wash when possible - they are required to dispose of the water through the sanitary sewer system, where it will be treated.