is to create an adjusted “depressionless” DEM in which the cells contained in depressions are raised to the lowest elevation value on the rim of the depression. Each cell in the depressionless DEM will then be part of at least one monotonically decreasing path of cells leading to an edge of the data set. A path is composed of cells that are adjacent horizontally, vertically, or diagonally in the raster (eight-way connectedness) and that steadily decrease in value. In the special case where flow routing is of interest within a depression, the original DEM values would be used rather than the depressionless DEM, and the flow paths within the depression would terminate at the bottom of the depression rather than at the data set edge.