ESTIMATIONS FOR PERCENTAGE OF IMPERVIOUS AREA BY THE USE OF SATELLITEREMOTE-SENSING IMAGERY

This study aims to evaluate the applicability of satellite imagery in estimating the percentage of impervious area in urbanized areas. Two m ethods of estimation are proposed and applied to a small urbanized wat ershed in Japan. The area is considered under two different cases of s ubdivision; i.e., 14 zones and 17 zones. The satellite imageries of LA NDSAT-MSS (Multi-Spectral Scanner) in 1984, MOS-MESSR(Multi-spectral E lectronic Self-Scanning Radiometer) in 1988 and SPOT-HRV(High Resoluti on Visible) in 1988 are classified. The percentage of imperviousness i n 17 zones is estimated by using these classification results. These v alues are compared with the ones obtained from the aerial photographs. The percent imperviousness derived from the imagery agrees well with those derived from aerial photographs. The estimation errors evaluated are less than 10%, the same as those obtained from aerial photographs .