Paper No. 271-3
Presentation Time: 2:00 PM
THE EFFECT OF UNREGULATED DISCHARGES INTO URBAN LAKES AND PONDS OF FRESHWATER ECOSYSTEM
The purpose of this study is to determine the prevalence of Fecal Indicator Bacteria (FIB) in soil and water samples at three recreational park sites within New York City. (1) Corona Meadow Park Lake, (2) Kissena Lake, and lastly (3) Baisley Pond. These three sites were chosen due to its wide range of land-use patterns in both freshwater and brackish water. Abnormally high concentrations FIB indicated that there is some sort of anthropogenic intrusion namely from neighborhood sewer lines. This study we looked specifically for the bacteria known as Escherichia Coli, Total Coliform and Enterococcus as these microbes are associated with the human gastrointestinal tract, and can give us an indication of a compromised sewer system contaminating the ecosystem. At each site, three cores were chosen that displayed a natural trajectory for water to flow into the waterbody during events of high rainfall. Starting at the shore of the waterbody and selecting another core 50 feet away, each core was at a general depth of 10-18 inches (depending on the randomness of the rock layout below the top soil). In each core, the soil tested positive for the presence of FIB, but its prevalence was not consistent at varying depths, i.e. there were higher concentrations of FIB at lower depths that at the surface. The conclusion was made that the FIB did display mobility during events of rainfall. To further verify this occurrence, column tests were conducted using the soils from each core, autoclaved water was used throughout the column tests to simulate rainfall and the infiltrated water was tested for FIB. The results showed that there were consistently high levels of FIB during multiple runs (4 runs) of the column test. These findings can have implications on the water quality of the recreational water bodies mentioned above and its impact on the fresh water eco-system.