What is stormwater runoff?
Stormwater runoff occurs when precipitation from rain or snowmelt flows over the ground. Impervious surfaces like driveways, sidewalks, and streets prevent stormwater from naturally soaking into the ground.
Why is stormwater runoff a problem?
Stormwater can pick up debris, chemicals, dirt, and other pollutants and flow into a storm sewer system or directly to a lake, stream, river or wetland. Anything that enters a storm sewer system is discharged untreated into the waterbodies we use for swimming, fishing, and providing drinking water.
The effects of pollution...
Polluted stormwater runoff can have many adverse effects on plants, fish, animals, and people.
- Bacteria and other pathogens can wash into swimming areas and create health hazards.
- 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 or die 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 water treatment costs.
- 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.
Follow the tips below to help us keep stormwater clean:
- Always clean up animal waste when walking your dog. Leaving pet waste on the ground increases public health risks by allowing harmful bacteria and nutrients to wash into the storm drain and eventually into local waterbodies.
- Use a commercial car wash that treats or recycles its wastewater, or wash your car on your yard so the water infiltrates into the ground.
- Repair leaks and dispose of used auto fluids and batteries at designated drop-off or recycling locations.
- Only use fertilizers on lawns sparingly.
- Don't overwater your lawn. Consider using a soaker hose instead of a sprinkler.
- Cover piles of dirt or mulch being used in landscaping projects.
- Compost or mulch yard waste. Don't leave it in the street or sweep it into stormdrains or streams.
- Inspect your septic system every 3 years and pump your tank as necessary (every 3 to 5 years).
- Don't dispose of household hazardous waste in sinks or toilets.
- Additional information: Stormwater brochure (English) | Proteccion de Agua de Lluvia (Español)
Commercial / Construction / Agriculture Tips
- Sweep up litter and debris from sidewalks, driveways and parking lots, especially around storm drains.
- Report any chemical spill to the local hazardous waste cleanup team. They know the best way to keep spills from harming the environment.
- Divert stormwater away from disturbed or exposed areas of the construction site.
- Install silt fences, vehicle mud removal areas, vegetative cover, and other sediment and erosion controls and properly maintain them.
- Prevent soil erosion by minimizing disturbed areas during construction projects, seed and mulch bare areas as soon as possible.
- Vegetate riparian areas along waterways.
- Store and apply manure away from waterbodies and in accordance with a nutrient management plan.
- Keep livestock away from streambanks and provide them a water source away from waterbodies.
- Helpful agricultural links to reduce nutrient loading: Colorado Agriculture Nutrient Clearinghouse and Colorado Agricultural Water Quality
- Additional information:
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