Two-thirds of coves, inlets and similar water bodies known as embayments, and one-third of ponds on the Cape, have unacceptably low water quality, according to a new report from the Association to Preserve Cape Cod (APCC).
The result in many cases is loss of ecological function, habitat, species diversity, and aesthetic value.
The problems are largely caused by poorly treated stormwater runoff, poor land use practices—like overuse of fertilizers—and most urgently, inadequately treated wastewater, according to the report.
Septic systems often allow excess nutrients like nitrogen to seep into the groundwater and end up in water bodies. Once there, these nutrients foster unhealthy plant growth and promote bacteria from algae blooms that can be toxic in certain concentrations.