| Tool Name | Overland Flow Distance to Channel Network |
| Tool ID | 4 |
| Library ID | ta_channels |
| Version | 1.0 |
| Author(s) | O.Conrad (c) 2001-14 |
Ali, K. F., De Boer, D. H. (2010): Spatially distributed erosion and sediment yield modeling in the upper Indus River basin. Water Resources Research, 46(8), W08504. doi:10.1029/2009WR008762
Freeman, G.T. (1991): Calculating catchment area with divergent flow based on a regular grid. Computers and Geosciences, 17:413-22. doi:10.1016/0098-3004(91)90048-I
Nobre, A.D., Cuartas, L.A., Hodnett, M., Renno, C.D., Rodrigues, G., Silveira, A., Waterloo, M., Saleska S. (2011): Height Above the Nearest Drainage - a hydrologically relevant new terrain model. Journal of Hydrology, Vol. 404, Issues 1-2, pp. 13-29, ISSN 0022-1694, 10.1016/j.jhydrol.2011.03.051. doi:10.1016/j.jhydrol.2011.03.051
O'Callaghan, J.F. & Mark, D.M. (1984): The extraction of drainage networks from digital elevation data. Computer Vision, Graphics and Image Processing, 28:323-344. doi:10.1016/S0734-189X(84)80011-0
| Name | Type | Identifier | Description | Constraints |
|---|---|---|---|---|
| Input | ||||
| Elevation | grid, input | ELEVATION | A grid that contains elevation data. | |
| Channel Network | grid, input | CHANNELS | A grid providing information about the channel network. It is assumed that no-data cells are not part of the channel network. Vice versa all others cells are recognised as channel network members. | |
| Preferred Routing | grid, input, optional | ROUTE | Downhill flow is bound to preferred routing cells, where these are not no-data. Helps to model e.g. small ditches, that are not well represented in the elevation data. | |
| Fields | grid, input, optional | FIELDS | If set, output is given about the number of fields a flow path visits downhill. For D8 only. | |
| Manning-Strickler Coefficient | grid, input, optional | FLOW_K | Manning-Strickler coefficient for flow travel time estimation (reciprocal of Manning's Roughness Coefficient) | |
| Flow Depth | grid, input, optional | FLOW_R | flow depth [m] for flow travel time estimation | |
| Output | ||||
| Overland Flow Distance | grid, output | DISTANCE | The overland flow distance in map units. It is assumed that the (vertical) elevation data use the same units as the (horizontal) grid coordinates. | |
| Vertical Overland Flow Distance | grid, output | DISTVERT | This is the vertical component of the overland flow | |
| Horizontal Overland Flow Distance | grid, output | DISTHORZ | This is the horizontal component of the overland flow | |
| Flow Travel Time | grid, output, optional | TIME | flow travel time to channel expressed in hours based on Manning's Equation | |
| Sediment Yield Delivery Ratio | grid, output, optional | SDR | This is the horizontal component of the overland flow | |
| Fields Visited | grid, output | PASSES | Number of fields a flow path visits downhill starting at a cell. For D8 only. | |
| Options | ||||
| Flow Algorithm | choice | METHOD | Choose a flow routing algorithm that shall be used for the overland flow distance calculation: - D8 - MFD | Available Choices: [0] D8 [1] MFD Default: 1 |
| Boundary Cells | boolean | BOUNDARY | Take cells at the boundary of the DEM as channel. | Default: 0 |
| Beta | floating point number | FLOW_B | catchment specific parameter for sediment delivery ratio calculation | Minimum: 0.000000 Default: 1.000000 |
| Default | floating point number | FLOW_K_DEFAULT | default value if no grid has been selected | Minimum: 0.000000 Default: 20.000000 |
| Default | floating point number | FLOW_R_DEFAULT | default value if no grid has been selected | Minimum: 0.000000 Default: 0.050000 |