Determination of Effective Impervious Area in Urban Watersheds

Principal Investigator:

John Gulliver, Professor, Civil, Environmental and Geo-Engineering


  • Bruce Wilson, Professor, Bioproducts and Biosystems Engineering

Project Summary:

Impervious areas are the most significant sources of pollutants in urban areas. Roads are not only a major component of these areas but also provide a pathway for urban runoff to drain into storm sewers. The overall objective of this research is to develop a method to accurately estimate the effective impervious area (EIA) using recently developed GIS databases. This project will investigate and expand upon two existing methods of estimating EIA in a watershed: (1) analysis of large rainfall-runoff data sets and (2) overlay analysis of spatial (GIS) data including land cover, elevation, and stormwater infrastructure. The latter method provides an estimate of connected pavement but requires the user to input the value of connected rooftops to determine the actual EIA value, which is the sum of these two quantities. The two methods will be applied to several urban catchments to evaluate their usefulness. The results will be used to: 1. Evaluate the connectivity of rooftops and roads; 2. Improve the GIS-based estimation technique, which is applicable to all watersheds; and 3. Expand the application of both techniques to additional sub-watersheds, with particular emphasis on newer developments and on catchments with more homogenous land uses.


Project Details: