Tools
Impervious Surface Analysis Tool
The Impervious Surface Analysis Tool (ISAT), which is available as a geographic information system extension, is used to calculate the percentage of impervious surface area of user-selected geographic areas (e.g, watersheds, municipalities, subdivisions). The National Oceanic and Atmospheric Administration (NOAA) Coastal Services Center and the University of Connecticut’s Nonpoint Education for Municipal Officials (NEMO) program developed this tool for coastal and natural resource managers.
In a watershed, the correlation between impervious surfaces and water quality has been well established, but determining the amount of impervious surface area can be a difficult and time-consuming process. ISAT was developed to help managers and planners calculate the area of impervious surfaces and relate this to impacts on local water quality.
Sample Functions
- Create polygons to represent conditions of good, fair, and poor water quality
- Calculate the percent impervious area and total impervious surface area of each selected polygon
- Incorporate land cover change scenarios to examine how changes influence impervious surfaces
User Requirements
- ArcView 3.x, 8.x, or 9.x
- Spatial Analyst
- Land cover grid
- Polygon data set for which percentage of impervious surface is to be calculated
- Set of land cover impervious surface coefficients calibrated for low, medium, and high population densities
- Optional population density theme
