Innovations in Onsite Waste Treatment Technology to Achieve Nitrogen Reduction Goals in Coastal Systems
Many estuaries and coastal embayments across the US are significantly impaired due to over-enrichment with nonpoint source nitrogen. Onsite septic systems are an important source of nonpoint nitrogen in many of these ecosystems (up to 80-85% of controllable load). Traditional septic systems do little to remove nitrogen or co-pollutants from effluent. Decades of wastewater disposal by such systems has caused widespread contamination of groundwater and receiving water bodies, with a wide range of adverse impacts, including promoting algae blooms, degradation of seagrass, impaired benthic condition, low dissolved oxygen, declining shellfish populations and in extreme cases, fish kills. Installing traditional wastewater treatment plants (WWTP) and municipal sewering can be prohibitively expensive in these areas. While some communities can be best served by a WWTP, other communities need cost effective, and efficient nitrogen removing septic systems. Enhanced innovative/alternative (IA) septic designs show promise for reducing nitrogen loads from a system, but only a limited number have been field tested and approved for general use, and fewer still have the capacity to reduce nitrogen loads to a degree necessary to meet Total Maximum Daily Loads for waterbodies. The first three presenters in the session will explore the scope of the problem, advances in septic system technology, and advances in septic system sensors. The second two presenters will describe field applications: the first will address the process of monitoring groundwater and environmental response to innovative septic systems on Cape Cod, and the second will describe an ongoing effort to install large numbers of innovative septic systems to address the water quality problems in Suffolk, Co., Long Island. This series of talks is will provide an overview of this important estuarine problem, discuss recent advances in research and technology to significantly reduce nonpoint source nitrogen pollution from septic systems, and highlight large-scale application to achieve mandated water quality goals for estuaries and coastal systems.
Coastal Water Resources