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- Stormwater Management Program
- Stormwater Pollution Prevention
Stormwater Pollution Prevention
Stormwater is the number one source of pollution to our waterways. As stormwater flows over paved areas, it picks up oil, trash, chemicals, fertilizers, sediment, and other pollutants.
Our stormwater system carries these pollutants directly to waterways and, ultimately, the Chesapeake Bay. Polluted stormwater degrades water quality and threatens the health of fish and other aquatic life.
You can help improve stormwater quality by disposing of oils and chemicals properly, minimizing or eliminating fertilizer use at home, picking up pet waste, and washing your car over a grassy area.
Your neighborhood storm drains lead directly to our local creeks, streams, and rivers. It's important to understand the impact your actions can have on our water systems. The following information provides details on pollutants that should be avoided to keep your waterways safe.
Prevent Nutrient Pollution from Fertilizer
Rainwater flowing over your lawn enters these waterways and ultimately ends up in Chesapeake Bay. The fertilizer you use on your lawn contains nutrients like nitrogen and phosphorous that can cause algae blooms in the Bay. Algae clouds the water, reducing light infiltration to critical underwater grasses. It also reduces the oxygen available in the water, causing fish kills.
Nutrient pollution has turned the Chesapeake Bay into one of the largest dead zones (low oxygen zone that cannot support any aquatic/plant life) in the nation.
How You Can Help
Follow these simple tips to protect our waterways from nutrient pollution:
- Test your soil for nutrient levels before fertilizing. Only apply what is needed.
- Fertilize in the fall, if at all.
- Use fertilizer sparingly. Follow the label.
- Consider organic fertilizers. The release nutrients slowly.
- Check the weather. Do not fertilize before it rains.
- Leave grass clippings on your lawn. They can generate 25% of your lawn’s yearly fertilizer needs.
Prevent Illicit Discharges
Any harmful materials entering storm drains end up in our waterways. Chapter 1096 of the County Ordinances prohibits illicit discharges, defined as any materials other than stormwater entering the stormwater management system.
Examples of illicit discharges include:
- Chlorinated pool water
- Oils, toxics, and hazardous materials
- Construction materials such as concrete
- Paint waste
- Vehicle and equipment wash water
How You Can Help
Follow these simple tips to protect our waterways from illicit discharges:
- Always properly dispose of used oil
- Wash your car on a grassy area
- Always dispose of pesticides, herbicides, and other hazardous materials at an authorized collection center
- Never blow grass clippings into the street or storm drain. Keep them on your lawn.
- De-chlorinate pool water prior to draining your pool and drain to a grassy area
- Never wash paint, concrete, or other materials into a storm drain.
- Report suspected illicit discharges by emailing us.
Prevent Bacterial Pollution to Our Waterways
When it rains, the harmful bacteria in dog poop such as E. coli and Fecal Coliform flow into our waterways. Dog waste also contains nutrients that can cause algal blooms.
There are several stream segments in Loudoun County that are considered impaired for bacteria, meaning levels are not considered healthy for humans or the environment. Loudoun dogs produce an estimated 4,253 tons of dog poop per year. Proper disposal of pet waste is critical to the health of our watershed.
How You Can Help
Protecting our waterways from bacterial pollution is easy:
- Always carry pet waste bags when you walk your dog.
- Scoop the poop in the ag and place it in the trash can.
- Educate others on bacterial pollution and encourage them to pick up after their pets.
For a free pet waste bag dispenser, email us.
Properly Drain Your Pool to Protect the Environment
Even at low levels, chlorine can be poisonous to fish and aquatic animals.
Pools draining to the storm sewer system must comply with Chapter 1096 of the County Ordinances, which requires removal of chlorine before water is discharged.
How to Properly Drain Your Pool
Protecting our aquatic life from pool water toxins is easy. Just follow these simple tips:
- Stop adding chemicals and let pool water stand for 10 days prior to draining.
- Test the pH. It should be between 6-8.
- Use a pool test kit to make sure chlorine and bromine are not detectable.
- Where possible, drain to a grassy area, not a storm drain.
- Never dump or rinse off chemical solutions in areas draining to storm drains.
- Never discharge backwash water to the storm drain.
Prevent Sediment Pollution
Sediment pollution can clog fish gills and smother critical habitat for aquatic life. Eventually, our waterways lead to the Chesapeake Bay, where sediment can cover critical oyster beds and underwater grasses.
Chapter 1096 of the County Ordinances seeks to prevent sediment from entering our watershed. One way we do this is to regulate construction activities that disturb land and can create potential sediment runoff.
How You Can Help
Follow these simple tips to protect our waterways from sediment:
- If you see muddy water running off a construction site into the stormwater management system or waterway, email [email protected]
- Combat erosion on your property. Plant grass, spread mulch over bare ground, or plant buffers of trees and shrubs to capture runoff and hold soil in place.
- Consider a rain garden to capture runoff.