Rho8 Flow Accumulation Tool

Rho8 Flow Accumulation

This tool calculates a flow accumulation grid (i.e. contributing area) using the Rho8 algorithm. This method is a single-flow-direction (SFD) approach, meaning that flow from each grid cell is directed to a single downslope neighbor, without allowing flow divergence.

Input parameters

• Input raster DEM or Rho8 pointer file; if a DEM is used, it must be depressionless – Select the file that will be modified.
• Log-transform the output values? – Applies a natural logarithm transformation to the flow accumulation grid, which helps visualize the distribution of contributing areas.
• Optional flag to request clipping the display max by 1% – Sets a limit on the maximum value displayed in the flow accumulation grid by excluding the top 1% of values.
• Is the input raster a Rho8 flow pointer rather than a DEM? – Determines whether the raster file used as input is a Rho8 pointer file, which specifies flow directions and requires different handling compared to a standard digital elevation model (DEM).
• Does the input Rho8 pointer use the ESRI style scheme? – Specifies whether the Rho8 pointer file follows the ESRI convention for encoding flow directions, which affects how the tool interprets the flow direction data.

Output parameters

• Name of the output raster file – Enter the name for the new raster.
• Output type; one of 'cells', 'specific contributing area' (default), and 'catchment area' – The "Output type" specifies the format of the flow accumulation grid: 'cells' shows the number of inflowing grid cells, 'specific contributing area' (the default) represents the catchment area divided by the flow width, and 'catchment area' displays the total upslope area contributing to each grid cell.

Current Location in toolbox

Rasters/Rho8 Flow Accumulation

Related Links

• Rho8 Flow Accumulation Whitebox Documentation