A GIS STUDY OF STREAMS ON STATEN ISLAND, NEW YORK

Recently, there has been emphasis on Urban Geology, specifically on urban watersheds. Staten Island has experienced urban flooding from storm water because urbanization has increased impervious surfaces. Staten Island watersheds have evolved and that is the reason for this study. Maps of Staten Island dating back to 1896 were georeferenced using Arc GIS^® in order to study past drainage patterns. Using the GIS, the past drainage basins were delineated. In order to compare past and present streams we have added (1)the present day existing streams; (2) the New York City Department of Environmental Protection(NYCDEP) “Bluebelts”; (3)the New York State Department of Conservation(NYSDEC) wetlands and (4)contour lines with a two foot contour interval. This study shows that many streams in the north part of Staten Island do not exist in the present day. Many of the Streams in the southern part of Staten Island have been modified with BMP’s(Best Management Practices) by the NYCDEP in order to manage storm water. It is now possible to compare the past and present drainage basins in terms of stream length, drainage basin areas, stream order, drainage density, bifurcation ratios, basin length, basin perimeter and sinuosity. The study is very important with respect to the study of urban watersheds.