The absolute value of these negative cells indicates the direction of flow. Unique label for each watershed basin. Each basin will be given a unique positive even integer. Areas along edges may not be large enough to create an exterior watershed basin. 0 values indicate that the cell is not part of a complete watershed basin in the current geographic region.
Values correspond to the watershed basin values.
Watershed basins are divided into left and right sides. The left-hand side cells of the watershed basin are given odd values which are one less than the value of the watershed basin. Surface runoff accumulation with the values modified to provide for easy display. All negative accumulation values are changed to zero. All positive values above the basin threshold are given the value of the basin threshold.