Characterization of Non-point Source Contamination from Septic Systems in Rural Hamlets, Ontario
Maria Digaletos, University of Waterloo, [email protected]
Carol Ptacek, University of Waterloo, [email protected]
Janis Thomas, Ont. Ministry of Environment & Climate Change, [email protected]
Abstract
Excessive nutrient loading to surface water bodies can lead to the development of eutrophic conditions, including deterioration of water quality and ecological stability. Direct assessment of anthropogenically-derived nutrient loading from septic systems can involve costly and time-consuming investigations of subsurface releases. There is a need for indirect assessment of septic system releases through measurement of septic system indicators within surface receiving waters. This study focused on measuring several indicators to delineate septic system discharge in rural hamlets. Over a 1-year period, surface water samples were collected from upstream and downstream sites in three rural hamlets to identify the release of contaminants, including nutrients, from septic systems to surface water quality. A suite of anthropogenic indicators was used, including an artificial sweetener (acesulfame-K), pharmaceuticals (caffeine, ibuprofen, gemfibrozil, and naproxen), and a host specific biological indicator (bacteriodales). Results indicate that non-point source contamination by septic systems is present in these areas. At two sites, downstream locations show elevated concentrations of anthropogenic indicators that are correlated with elevated nutrient concentrations. These results suggest that in densely populated rural areas near streams, elevated nutrient concentrations may be derived from septic systems.
1. Keyword
nutrients
2. Keyword
Grand River
4. Additional Keyword
septic systems
5. Additional Keyword
pharmaceuticals
6. Additional Keyword
artificial sweeteners