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:
- Pick-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 because these facilities recycle water, and properly treat the discharge sending it to a wastewater plant.
- Repair vehicle leaks and dispose of used auto fluids and batteries at designated drop-off or recycling locations.
- Don’t wash trash cans as you may create a bigger problem by exposing your neighbor to a higher level of unknown pollutants. Disregard any printed cleaning instructions on your curbside trashcans. Do not rinse containers with water since the discharge may reach the street gutter releasing a vast unknown amount of bacteria impacting water quality.
- Use fertilizers such as Nitrogen and Phosphorus on lawns sparingly. Excess nutrient creates algae blooms in lakes and rivers, depleting oxygen level for aquatic life.
- Don't overwater your lawn. Avoid wasting water as well as unnecessarily washing off sediments and excess nutrients from your yard.
- Cover temporary piles of dirt or mulch being used in landscaping projects. Never store materials in the street. This is a safety hazard as well as excess irrigation water or rain may wash the materials along the curb flow into the storm system.
- Compost or mulch yard waste. Don't leave it in the street, nor sweep it into stormdrains or streams.
- If applicable, inspect your septic system every 3 years and pump the tank as necessary (every 3 to 5 years).
- Don't dispose of household hazardous waste in storm drain, interior sinks, nor 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.
- Do not powerwash drive-thru, nor dumpster areas without collecting the soapy wastewater, and disposing it properly to protect the environment. Consult with a licensed professional prior performing outdoor washing activities and establish clear standard operation procedures for employees.
- 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 and maintain silt fences, vehicle mud removal areas, vegetative cover, and other sediment and erosion controls.
- 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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