The Nitrogen Problem

Nitrogen is a normal part of plants and animals, but too much nitrogen is degrading the ponds, estuaries and coastal waters of Falmouth and Cape Cod.

Nitrogen enters these waters from septic systems, fertilizers, animal waste, roadway runoff and the atmosphere.

97% of Falmouth's homes and businesses depend on septic systems to treat their wastewater. Human waste, especially urine, contains a great deal of nitrogen. Even Title V-compliant septic systems allow more than 75% of the nitrogen to enter the groundwater, which ends up in our coastal waters.


When excess nitrogen enters these saltwater environments, it causes eutrophication. Plants, especially algae, love nitrogen and grow rapidly when it is available in abundance. Then, these plants die and decompose - using up the oxygen that other plants like eelgrass need to grow, and fish need to survive. Murky, smelly water is another unpleasant result of eutrophication.
To solve this real problem, we first need to know how much nitrogen is too much.

Total Maximum Daily Load

Fortunately, the Massachusetts Department of Environmental Protection (MassDEP) and the Massachusetts Estuaries Project (MEP) have figured out how much nitrogen can be used by an estuary before the water quality is negatively impacted. This quantity is known as a Total Maximum Daily Load (TMDL). The TMDL is the benchmark for determining how much nitrogen we need to either remove from the estuaries, or keep out of the estuaries in the first place. Our goal is to meet the TMDLs, and restore the water quality in these invaluable natural resources.

Additional Information