Fertilizers, yard debris, animal waste, stormwater runoff, sewage discharges and overflows: all are sources of nutrient pollution in our estuary. Many activities we take for granted contribute to nutrient pollution of our waterways: fertilizers carelessly spread or scattered and over watered, pet and animal waste washed by rain into storm drains or creeks, leaves and grass clippings blown into the street, soap and chemicals used in washing a car hosed down the driveway into storm drains. These activities send nitrogen and especially phosphorus into our waterways where they accelerate plant growth resulting in cultural eutrophication:
Too much nitrogen and phosphorus in the water causes algae to grow faster than ecosystems can handle. Significant increases in algae harm water quality, food resources and habitats, and decrease the oxygen that fish and other aquatic life need to survive. Large growths of algae are called algal blooms and they can severely reduce or eliminate oxygen in the water, leading to illnesses in fish and the death of large numbers of fish. Some algal blooms are harmful to humans because they produce elevated toxins and bacterial growth that can make people sick if they come into contact with polluted water, consume tainted fish or shellfish, or drink contaminated water. (EPA: The Problem)
From the Three Mile Creek Watershed Management Plan, 9-5-2014: Gross Pollutants (trash, organic debris, sediment) are a primary source of oxygen demand, nutrients, and pathogens in the Three Mile Creek watershed and other watersheds, degrading surface water quality and habitat.
From the Three Mile Creek Watershed Management Plan, 9-5-2014: Unmaintained channels accumulate organic debris that rots placing an additional oxygen demand on the creek and degrading surface water quality and habitat. (Location: Twelve Mile Creek at Fontaine Drive).
Left Algae bloom resulting from excessive nitrate and phosphate concentrations in surface waters.
From the Fowl River Watershed Management Plan, 3-30-16, pp 172: Nutrient-impaired waters are characterized by numerous problems related to growth of algae, other aquatic vegetation, and associated bacterial strains. Blooms of algae and associated bacteria can cause taste and odor problems in drinking water and decrease oxygen concentrations. Toxins also can be produced during blooms of particular algal species. Nutrient-impaired water can dramatically increase treatment costs required to meet drinking water standards.
Common Sources: agricultural practices, stormwater runoff, wastewater overflows and discharges, and fossil fuel consumption (airborne pollution impacts the water, too).
Things you can do: Use phosphate-free detergents and cleaners, pick up after your dog, use a car wash or wash your car on the grass with an eco-safe detergent, clean and maintain your septic system, properly clean parking lots (business owners), use water and energy-efficient fixtures in your home, carpool or use public transportation.