Phosphorous Loadings to Streams in Residential Watersheds Using On-site Wastewater Systems in Comparison to Centralized Sewer

It is well documented that excessive nutrients can degrade ground and surface water quality. Phosphorus is a limiting nutrient in algae growth under certain circumstances, which can lead to fish kills and environmental problems (Fear et al. 2004). Waste water is a major source of nutrients in residential ground and surface waters. This study attempts to compare the nutrient loads to groundwater from two similar watersheds, one which uses on-site waste water treatment systems (OWTS), or septic systems, and another which uses a municipal sewer system. Physical characteristics such as rainfall, flow volume, soil types; and chemical parameters such as pH and nutrient and ion concentrations will be monitored strategically to gain understanding of what effects each system has on the local water quality. Surface water will be compared among the different watersheds to distinguish what differences can be expected among two different land uses, and compared to the effluent of municipal wastewater treatment plant.  Soil borings will capture characteristics of soils such as phosphorus and mineral content at each site. The overall goal is to better understand mechanisms and variances in nutrient loads to surface waters among sites using OWTS and municipal sewer in the context of Pitt County, NC, with a focus on phosphorus. As bulk this paper should add to the aggregate of evidence showing human interaction with the natural environment can have discreet measurable and sometimes acutely negative effects.