Stormwater is the water from rain, that travels into the storm drain.
Stormwater starts off clean. Stormwater flows directly into our lakes and streams and is almost never treated. So everything stormwater collects is carried directly to gutters, storm drains, canals, drainageways and finally ends up in our local rivers and streams untreated! Examples of locations where runoff and detritus are collected from include:
- Business parks
- Construction sites
- Land surface
- Parking lots
- Sidewalks, etc.
It is estimated that more than one-half of the pollution in our nations waterways comes from stormwater runoff.
In the past, it was thought that water pollution was caused mainly by industrial and municipal wastewater treatment plant discharges. A lot of effort was put into cleaning up these "point sources" of wastewater. Now, the effort is being expended to clean up "non-point source" pollution, water pollution that is generated all over and carried to streams in pipes and ditches.
The problem with non-point source pollution is that it is very expensive to treat and discharge. Treatment facilities would have to be very large to treat storm peak flows and would sit unused more that 95% of the time.
Improve Stormwater Quality - Treat the Source
The best way to improve stormwater quality is to treat the source - don't let runoff get polluted in the first place. These methods are called Best Management Practices (BMPs). Examples of some BMPs: Recycle your grass clippings for composting in your garden, wash your car in the grass to allow wash water to percolate through the soil.