Water Resources Research Act Program

Details for Project ID 2013GA330B

Tracking the impact of on-site wastewater treatment systems on stream water quality in the Metro-Atlanta area

Institute: Georgia
Year Established: 2013 Start Date: 2013-03-01 End Date: 2014-09-30
Total Federal Funds: $18,000 Total Non-Federal Funds: $36,000

Principal Investigators: Mussie Habteselassie, David Radcliffe

Abstract: Increased population growth in Georgia in the last decade has led to more reliance on onsite wastewater treatment systems (OWTS) for wastewater treatment and disposal. OWTS have the potential to affect surface waters that are the main sources of public water supplies. As widely as OWTS are used, their impact on water quality is not well defined or included in land use planning projects. The specific objective of this proposed study is to use bacterial and elemental methods of source tracking to investigate if OWTS are impacting the water quality of streams found in urbanizing watersheds of the Metro-Atlanta area. The proposed project will complement an existing project that involves monitoring a total of twenty four watersheds that are found in Gwinnett County for three years. The watersheds are grouped under two categories, those having high density of OWTS and those having low density of OWTS. In this project the streams in the watersheds are sampled under base- and storm-flow conditions several times a year and analyzed for EPA mandated microbial water quality indicators (E. coli and enterococci) and different nitrogen forms, in addition to in situ measurements of some standard water quality parameters (pH, specific conductance, temperature and dissolved oxygen) and stream flow measurements. Measurement of these water quality parameters does not necessarily indicate the contribution of OWTS to the water quality. The benefit of the existing project can be significantly enhanced by including a source tracking analysis to conclusively affirm the contribution of the OWTS to the stream water quality. We are proposing to do that by looking at bacteria (fecal enterococci and Bacteroides), phosphorus, and elemental isotopic ratio analysis (e.g., boron, nitrogen, and oxygen) to source-link the contaminants as being either from OWTS or not. The study will provide information for the development of educational materials on OWTS aimed at students, installers, pumpers, state employees and public OWTS owners involved in the monitoring and operation of these systems.