A Denver stormwater violation can be more ordinary than chemicals

A stormwater violation brings to mind a leaking drum with a warning label, but the real line is far more ordinary than that. Anything besides rainfall and snowmelt that enters a storm drain can count as a pollutant, and pollutants in stormwater are what Denver calls an illicit discharge.

The reason that net is so wide comes down to where the water goes. Storm drains are not the sewer. What runs into an inlet flows straight through to local waterways without any treatment, picking up whatever it touches along the way. Around Denver, those waterways feed the South Platte and the creeks that join it, so the curb in front of a house is closer to the river than it looks.

That puts a lot of everyday chores in the same category. Washing a patio into the gutter, letting soapy car-wash water run down the street, blowing yard debris into the curb, or rinsing paint tools outdoors all send material into the storm system. The fix is usually small once you see it: before you clean, wash, or drain anything outside, follow the water. If the path leads to the street or an inlet, route it somewhere it can soak in or be collected instead. Denver’s common-pollutants page is where the difference between plain rainwater and a discharge the city may act on is spelled out.