Summary

This map shows the increase in developed land via increase or change in impervious surface over 3 time periods; 1990, 1996 & 2000 using 1986 as the base time period. And as regional impervious surface increased within the same study area, it is logical to conclude that regional green space / open space decreased. Analysis of the COG portion of the Washington Metropolitan Area using satellite imagery revealed that our region’s impervious surface (paved, developed or otherwise non-vegetated) increased 5.6% from 12.2% to 17.8% in the 14-year study period between 1986 and 2000. To put this into perspective, our analysis looked at the 1986 development conditions and measured the existence of impervious surface. This data was then compared to the data for the subsequent analysis periods (1990, 1996 & 2000), it showed that this region had increased its impervious surface by nearly half between 1986 and 2000.