Stream and catchment roughness
The hydraulic equations used to describe flows and their characteristics include various roughness factors such as Manning's n, Chezy's C and the Colebrook-White e or k factor. The rougher the pipe or channel, the greater the friction losses and slopes for hydraulic grade lines.
In open channels, increasing roughness usually results in higher water levels and slower flow velocities (complications might occur due to sub- and supercritical water surface profiles).
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IL-CL Sub-Catchment property sheet
This is used to enter data for the ARR 2019 IL-CL model. Different sheets are used for Horton (ILSAX) and the rational method, and other formats are used for storage routing model sub-catchments. At the top there is a text box for the sub-catchment ...
Sub-Catchment property sheet (superseded)
The older form of the property sheet for Horton (ILSAX) sub-catchments is shown below. A similar form of model was used with the rational method and extended rational method procedures, with the land-use types being impervoius and pervious, rather ...
Stream routing reach tool
This link type, , is used to connect nodes and sub-catchments in RORB and WBNM storage routing models that can be used to model broad-scale rural and urban catchments. It performs non-linear routing in these models (the RAFTS storage routing model ...
Sub-Catchment drawing tool
This tool, , is used to draw sub-catchments in the Main Window. Since it is wrong to place a sub-catchment directly over a pit, the pit will snap to the top, right hand side of the pit. It can then be moved to other sides of the pit, if desired. ...
Stream routing reach
This link type, , is used to connect nodes and sub-catchments that form parts of the RORB and WBNM storage routing models which can be used to model broad-scale rural and urban catchments (the RAFTS type model employs the same overflow routing link ...