Stormwater Runoff
What is stormwater runoff?
Stormwater runoff is any drop of water that does not sink into the ground or evaporate.
The next time you are outside in a storm, take a moment to watch how the rain moves. Notice it flowing out of downspouts, moving across sidewalks, running along roadway curbs, and pouring into catch basins and grates.
Rain falling on a pervious surface, such as a forest or a meadow, will soak into the ground or be used by the plants. Our rooftops and roadways are different. Rain falling on these impervious surfaces does not soak in. This rain picks up speed and pollution as it flows into drains and then into our waterways.
How do pollutants impact the health of our waterways?
Stormwater carries pollutants from many sources such as sediment, fertilizers, septic systems, pet waste, and livestock manure into the Bay. Increased pollution:
Destroys aquatic habitat and reduces oxygen, killing fish and other aquatic organisms
Contaminates waterways with bacteria and viruses, making swimming, fishing, and recreating unsafe
pollution Sources in Anne Arundel County
nutrients
Nutrients are the main elements required for plant growth. While nutrients are natural, high levels are harmful to our waterways. When stormwater runoff washes nutrients like nitrogen and phosphorus into the Bay, the elevated levels over-stimulate aquatic plant growth. This creates algae blooms, an exploding algae population that blocks sunlight to underwater grasses and leads to sudden drops in oxygen levels. These areas are called dead zones because the oxygen level is too low for aquatic life to survive.
Nutrient pollution sources include fertilizers, animal waste, failing septic systems, road salts, lawn clippings, and leaves.
Sediment
Sediment is eroded material that settles after movement from wind, water, and other natural processes. These loose soil particles smother sedentary aquatic plants and animals and block light from aquatic life. Without sunlight, aquatic grasses cannot produce the oxygen needed to support life. Additionally, pollutants including oils, metals, bacteria, and nutrients tend to attach to soil particles, making sediment an even greater source of pollution.
Sediment pollution sources include cleared construction sites and exposed earth, erosion, dirt, and grit from parking lots, roads, and sidewalks.
Toxic Substances
Toxic substances are chemical contaminants that can impact the health of humans and wildlife. These contaminants can build up in the environment over time, affecting an organism’s life span and ability to reproduce. As predator eats prey, these contaminants make their way up the food chain.
Toxic substance pollution sources include pesticides, prescription drugs, paint, motor oil, and other household chemicals.
Bacteria & Viruses
Bacteria and viruses found in water breed disease, causing health-related issues in humans and animals alike. Bacterial contamination can lead to fishing areas and swimming beaches in Anne Arundel County as well as the Chesapeake Bay.
Bacteria and virus pollution sources include pet waste, failing septic systems, and organic fertilizers like manure.