This website provides a series of maps and statistics about land cover, impervious surface area and landscape change, derived from satellite imagery, in Minnesota from 1986 to the present. Minnesota is one of the first states to have multiple dates of land cover and impervious surface, and change data, mapped statewide using satellite imagery. Other surveys have been performed by various means on smaller scales, but none have had the large area coverage as well as the historical depth of information. Quantifying the amount of impervious surface area, an important indicator of environmental quality, is particularly valuable because of its effects on stormwater runoff and lake and stream quality.
Again, computational intensiveness isn't clear, but project uses a variety of sources for data, works with the Minnesota Pollution Control Agency and displays data via UMN MapServer.