MICROBIAL CONTAMINATION FROM NUTRIENT-RICH FRESHWATER INFLOWS IN LAKES AND URBAN ESTUARIES OF NEW YORK CITY, USA

Increase of nutrients and organic material in recreational waters as a result of urban anthropogenic activities pose serious health risks. The impact is demonstrated in the increased levels of microbial activity in the water and sediment columns of recreational waters located in the area of New York City (NYC). The purpose of this study is to understand the extent of microbial contamination in the brackish and relatively fresh water environments of recreational waters of NYC, such as Jamaica Bay, a wetland estuary environment and Meadow Lake, a man-made body of fresh water. The physical water parameters are somewhat similar for pH (7.6 to 8.8), temperature (21.3-23.1 ^oC), dissolved oxygen (9.1-11.1 mgL^-1), and different for salinity (JB: 21.6-28.7 ppt and ML: 3.9-5.1 ppt). However, both environments receive nutrients from several point and non -point sources including: combined sewer overflows/storm water (CSOs), sediments loading from surroundings, and subsurface groundwater discharge. While recent improvements in storm water retention infrastructure were expected to reduce the loading of pathogenic bacteria such as E. coli and enterococci into Jamaica Bay, a continuous increase in infrastructure, since its inception in 1939, has made Meadow Lake more accessible to residents resulting in increased human activity. This project aims to capture and compare the microbial concentrations by conducting a bi-weekly sampling from Jamaica Bay and Meadow Lake using the EPA approved IDEXX method for microbiology analysis in the water and sediment columns. Fecal coliform concentrations for Jamaica bay were found to be above the state bathing standard with a geometric mean of 1200 counts/100 mL. Enterococci concentrations were found to be an order of magnitude higher than previous concentrations of 3counts/100 mL. Preliminary results from Meadow Lake were also found to be well above the state standard for bathing and boating with average concentrations of 2435, 319 and 101counts/100 mL for fecal coliform, E. Coli and Enterococci respectively. Microbial sediment counts were very striking with a range of 1-24196 counts/100 ml. The study will be continued to identify the primary sources of this contamination and its variation, if there is any.