GIS ANALYSIS OF 30 YEARS OF WATER QUALITY DATA AT GATEWAY NATIONAL RECREATION AREA: AN UNDERGRADUATE RESEARCH PROJECT

Jamaica Bay is a shallow, urbanized estuary that lies within the jurisdiction of the Gateway National Recreation Area of the U.S. National Park Service. Approximately 89% of the nitrogen load to Jamaica Bay comes from wastewater treatment plants and the Bay exhibits many symptoms of cultural eutrophication. During rain events, the discharge of raw sewage into the Bay from combined sewer overflows poses a human health risk. For the past 30 years, the National Park Service has been conducting biweekly monitoring of water quality parameters in Jamaica Bay during the summer months. The measured parameters include water temperature, salinity, nitrate, orthophosphate, chlorophyll a, dissolved oxygen, pH, fecal coliform bacteria and Enterococcus. These data are included in hardcopy annual reports and are available in the EPA’s STORET database. In cooperation with staff at Gateway National Recreation Area, undergraduate students at Brooklyn College have consolidated the data into a single georeferenced database to allow spatial and temporal analysis using Geograpical Information System (GIS) tools. This work will allow an examination of long-term trends in water quality parameters as well as to determine the short-term drivers as a function of location. In addition, the students are obtaining valuable skills in GIS techniques and data analysis. For the initial analysis, we chose to examine the spatial and temporal variability of parameters during the year 2009. This year was chosen because it is the wettest summer season recorded during the past decade. The analysis will provide an understanding of the relationship between the measured parameters and the proximity of the sampling date to antecedent precipitation events. This understanding will allow a richer interpretation of long-term trends which may be biased by the choice of sampling dates in any given year.