What is Stormwater Pollution?
When it rains, some of the rainwater soaks into the ground, and part of it flows over the ground and directly into creeks, streams or rivers. This water that runs off into the river is called runoff, or sometimes stormwater runoff. Clever, huh? Sometimes this stormwater runoff gets polluted. Pollution is anything that harms natural resources, whether it is air, soil, or in this case, water. Sometimes the pollution is something you can see, like trash floating on top of the water. Other times you can’t see the pollution at all, like when motor oil from a car washes into a nearby creek. Polluted runoff is the number one cause of water pollution in the United States, and eastern Washington is no exception. So, who is to blame? Who is making the water that we drink and swim in dirty? We all are… do your part, one drop at a time. Through the information on this website, now you know better!
Why is stormwater pollution a concern?
It is of concern for two main issues: one related to the volume and timing of runoff water and the other related to potential contaminants that the water is carrying from human and animal activities. These contaminants are picked up as water from a storm or garden hoses and sprinklers drain from streets, parking lots and lawns and enter the system through our catch basins and storm drains. From there, they are transferred straight to rivers and streams untreated.
Anything that is dumped or dropped on the ground or in the gutter contributes to stormwater pollution. Much of it is not biodegradable and is harmful to marine life and cleanliness of our water that we swim in and drink.
Is stormwater treated before it reaches the river?
No! Stormwater systems flow directly into the rivers, lakes and streams. The cost of treating stormwater would be so high that it would exceed available resources.
Is there a difference between a storm drain and a sewer drain?
Yes! They are two completely separate drainage systems. The sewer system takes all household wastewater from toilets, showers and sinks and routes it through your plumbing system and directs it to a treatment plant.
The storm drain is intended to route rainwater quickly off the streets during a heavy storm. Unfortunately, it takes all the runoff along with it. Chemicals, trash, debris from lawns, parking lots and streets, either intentionally or accidentally spilled, goes straight into our waterways.
The effects of pollution
Polluted stormwater runoff can have many adverse effects on plants, fish, animals and people.
- Sediment can cloud the water and make it difficult or impossible for aquatic plants to grow. Sediment also can destroy aquatic habitats.
- Excess nutrients can cause algae blooms. When algae die, they sink to the bottom and decompose in a process that removes oxygen from the water. Fish and other aquatic organisms can’t exist in water with low dissolved oxygen levels.
- Bacteria and other pathogens can wash into swimming areas and create health hazards, often making beach closures necessary.
- Debris – plastic bags, six-pack rings, bottles, and cigarette butts – washed into waterbodies can choke, suffocate, or disable aquatic life like ducks, fish, turtles, and birds.
- Household hazardous wastes like insecticides, pesticides, paint, solvents, used motor oil, and other auto fluids can poison aquatic life. Land animals and people can become sick from eating diseased fish and shellfish or ingesting polluted water.
Polluted stormwater often affects drinking water sources. This, in turn, can affect human health and increase drinking water treatment costs.