Abstract |
Estimates of impervious surface acreage in 1990 and 2000 were generated for a 48-town region in coastal New Hampshire, including the 43 towns within Zones A and B of the New Hampshire Estuaries Project (NHEP) Area. The estimates were based on applying both traditional and subpixel classification techniques to 30-meter Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) satellite image data. The classifications indicated that 4.3% (31,233 acres) of the study area was impervious in 1990, with an increase to 6.3% (45,445 acres) impervious coverage in 2000. At the subwatershed level, the Portsmouth Harbor subwatershed recorded the highest percentage of impervious surface acreage in both 1990 and 2000, with 19.8% coverage (2,310 acres) and 25.5% coverage (2,975 acres) respectively. |