THE IMPACT OF URBANIZATION AND LAND-USE ON SURFACE WATER QUALITY IN QUEENS COUNTY OF NEW YORK CITY

Most of the urban surface water bodies are under serious threats due to reckless recreational activities and contaminated water inflows. This study aims to investigate the water quality of several fresh water bodies in an urban setting. Seven ponds/lakes in Queens County, New York City were selected to cover wide ranges of urban settings and land-use patterns. The initial report covers the water quality in three different ponds. Water samples were collected from Meadow Lake (N40º 44.100’ W73º 50.328’), Oakland Lake (N40º 45.527’ W73º 45.468’) and Baisely Ponds (N40º 40.100', W73º 47.000’) to monitor physical and chemical parameters including pH, ORP, Temp., Conductivity, Salinity, Turbidity, Dissolved oxygen, common anions (F^-, Cl^-, Br^-, NO₂^-, NO₃^-, PO₄^3- and SO₄^2-), NH₄⁺ and a few trace metals (Cu, Cd, Pb and Zn). YSI (model- 600QS-ORP-O) multi-probes instrument was used to monitor a few parameters on site. CHEMetrics self filling reagent ampules and V-2000 multi-analyte photometer were used to determine DO, NO₂^-, NO₃^-, PO₄^3- and NH₄⁺. The standard addition calibration curve was developed by spiking the reference standard to the sample matrix in the field. The final concentrations were obtained using the slope from this standard addition calibration curve with a r² value of >0.997. Two sets of samples were collected from three or more locations in each pond/lake upon filtration through 0.45 μm membrane filters. The filtered and acidified (1% optima grade HCl) set was stored at room temperature for trace metal analyses by CSV (Cathodic Stripping Voltammetry). The filtered and not acidified samples were collected on ice and carried to laboratory for anion analyses. Lachet FIA 8500 series II Nutrients analyzer coupled with Ion Chromatography (IC) was used to determine the anionic concentration and nutrients loading. Not acidified samples were stored in freezer (-52^oC) immediately after returning to the laboratory from field for analysis of nutrients. The preliminary data indicates that in slightly saline Meadow Lake (conductivity 14627 μS/cm) water is relatively reducing with ammonia concentration of 3.22 mgL^-1 while Oakland lake with conductivity (1086.67μS/cm) showed a higher level of nitrate concentration ( 3.0 mgL^-1). The investigation is being continued in four ponds with different physico-chemical settings.