HOLISTIC APPROACH FOR COASTAL WATERSHED NITROGEN MANAGEMENT

A holistic approach to nutrient management allows for easy identification of the problems and development of management solutions. Eutrophication is the leading cause of water quality impairment in the U.S and nitrogen enrichment is a significant issue in coastal areas. Decentralized wastewater management systems utilizing nutrient removal technologies provide a wastewater management option that is cost effective and protective of the environment, and avoids the need for centralized sewering.The Great, Green, and Bournes Ponds area in Falmouth, Massachusetts are classified as “significantly impaired” or “severely degraded” due to excess nitrogen loading from non-point sources. To improve the water quality, a holistic approach to nitrogen management was proposed for Falmouth. Conceptually, the watershed is divided into three zones based on their contributions to the Ponds. Then a nitrogen removal approach for each zone is developed based on the magnitude, location and type of nitrogen inputs within each zone.The holistic approach employs an alternative denitrification technology, NITREX™, which can be used in a variety of applications. In Falmouth proposed applications of the NITREX™ technology included:individual or cluster on-site systemspermeable reactive barrierspump and treat systems with constructed wetlandsThe appropriate combination of NITREX™ applications would be used in each area. Examining the nitrogen loading on a watershed scale allows the most environmentally and economically optimal treatment options to be employed in each zone of the watershed.