Use of impervious surface data obtained from remote sensing in distributed hydrological modeling of urban areas - Urban Remote Sensing: Monitoring, Synthesis and Modeling in the Urban Environment - page 242

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Use of impervious surface data
obtained from remote sensing in
distributed hydrological modeling
of urban areas
Frank Canters, Okke Batelaan, Tim Van de Voorde, Jarosław
Chormanski and Boud Verbeiren
While the increase of impervious surface cover in urbanized areas has a clear impact on urban hydrological
processes, the relationship between flood conditions and urban development has been poorly studied. This chapter
focuses on a case study demonstrating the impact of different remote sensing methods for characterizing the
distribution of impervious surfaces on runoff estimation, and how this affects the assessment of peak discharges in
an urbanized watershed in the Brussels Capital Region, Belgium. In the study use is made of WetSpa, a grid-based
spatially distributed hydrological model adapted to incorporate information on the proportion of different types of
land-cover at grid cell level. The study shows that use of detailed information on the spatial distribution of
impervious surfaces, as obtained from remotely sensed data, strongly affects local runoff estimation and has a clear
impact on the modeling of peak discharges. Little difference, however, is observed between results obtained with
impervious surface maps derived from high-resolution remote sensing data (IKONOS, 4 m resolution) and
sub-pixel estimates of impervious surface cover derived from satellite data matching the model's resolution
(Landsat, 30 m resolution).