This polygon dataset was derived from a raster dataset that was developed by calculating the maximum rate of change between elevation points that are 30 meters apart in a 30 meter digital elevation model grid.
This dataset shows two classes of sloped areas. Class1 includes slopes from 12 to 18 percent, and class 2 includes slopes greater than 18 percent.
However, there is no guarantee that such slopes exist within any given polygon in this dataset.
This dataset is not suitable for determining the precise location or actual size of areas that are undevelopable due to slopes, but merely the general location of areas where development might be constrained due to steep slopes.
Based on visual inspection when laying the dataset over 2000 orthophotos, the steep slope classes appear to be a reasonable representation of areas of steep slope, although these results have not been field checked.
Note: This dataset was revised 10/25/2001. The previous version significantly over represented the areas of steep slope.