This story was written by the Our Gem Collaborative team for the CDA Press on Wednesday, April 22, 2020. Read the original article.
When it rains or snow melts, where does that water go? In a natural landscape, water is quickly absorbed into the soil, but in urban and developed areas with impervious surfaces, water cannot soak into the ground and instead flows over surfaces as stormwater runoff. Runoff flows over parking lots, roads, roofs, and sidewalks picking up all sorts of pollutants: sediment, fertilizers, litter, petroleum, pet waste, and metals as it rushes along.
Traditionally, the objective of stormwater management has been to divert runoff as quickly as possible to prevent flooding. As a result, most cities have a series of storm drains and catch basins to transport runoff from streets and parking lots. Curbside stormwater grates may drain into a drywell (a porous-walled chamber that allows water to slowly soak into the ground) or divert stormwater directly to streams, rivers, ponds and lakes, completely untreated. Polluted stormwater negatively affects fish, wildlife, and recreation. Modern practices encourage reducing the amount of stormwater reaching surface waters by allowing water to slow down and filter into the ground. Infiltration basins called swales achieve this throttling back of rushing stormwater by trapping it in areas of shallow channels with gently sloping sides. They are often grassy but can also be filled with wetland plants or rocks.
Where you live determines what happens to your stormwater. Stormwater is diverted to swales and catch basins in the cities of Hayden, Post Falls, and about half of Coeur d’Alene. In the southern half of Coeur d’Alene, stormwater primarily flows into Coeur d’Alene Lake or the Spokane River, untreated. The City of Coeur d’Alene is working to increase the number of swales and other porous surfaces to limit the amount of water entering surface water, but it takes time and resources to change the infrastructure. In the meantime, it is best to keep the stormwater that flows to our lake and river as clean as possible.
Even if you don’t live on or near the waterfront, your stormwater runoff likely enters storm drains that dump directly to surface water. Homeowners are responsible for stormwater retention or discharge from their property. You can help by reducing the amount of impervious surface on your property and directing runoff into an area where water can soak into the soil to minimize runoff. You can inventory stormwater issues for your property using the template available in the Coeur d’Alene LakeASyst manual (www.uidaho.edu/OurGem). Remember that you may not see the impacts created by stormwater coming off your property: water may quickly run off your driveway, along the curb, into a clogged culvert, and flood a road two miles down. We all share the responsibility of minimizing stormwater and preventing water pollution. Your property alone is probably not a significant source of pollution, but the cumulative effect of tens of thousands of properties can have a substantial impact on water quality. If you reduce stormwater coming off your property, the entire drainage system will be healthier with less water to manage. Stormwater is unavoidable, but its impacts can be reduced by keeping harmful chemicals and pollutants out of runoff. Pollution prevention is the easiest way to keep the Coeur d’Alene Basin safe, clean, and inviting.
What you can do:
- Be aware of swales on or near your property
- Never dump anything into storm drains, dry wells or drainage swales
- Keep storm drains clear of trash and leaves to maintain proper drainage
- Pick up pet waste – don’t put it in the gutter or storm drain
- Wash your car over grass or gravel or at a commercial carwash
- Never allow roof gutters to drain directly into the street or storm drains
- Avoid spilling fertilizers and pesticides in areas that can wash into storm drains
- Reduce impervious surfaces on your property
- Clean up oil stains and avoid outdoor spills of antifreeze, brake fluid, and other engine fluids
- You can report stormwater violations to your municipality