Converting Channels to River Reaches

Channel objects can be converted to River Reach objects. The convert channels to reaches tool can be used to convert imported channels into river reach objects. The join reaches tool can then be used to merge connected reaches into a single reach.

To convert channel objects to river reach objects:

1. Select the channel objects to be converted in the GeoPlan Window
2. Select Convert selected channels to river reaches from the Model menu

For each selected channel link:

• The channel link is converted into a river reach link
• An upstream and downstream river section is created with the shape of the channel profile specified in the channel's associated shape:
  • Sections are inserted perpendicular to the river reach link intersecting the upstream and downstream nodes of the link. The point of intersection of the link is located at the lowest point of the section. If there is not a unique low point, the point of intersection will be placed between the extreme low points
  • Bed level is calculated as channel profile depth + channel US / DS invert level
  • Roughness Manning's n is set to channel profile Roughness Manning's n values if channel shape Roughness type is set to N (Manning's n). If Roughness type is set to MANNING or CW, roughness values are converted:
    • Section roughness calculated as 1/(1/n) if channel shape Roughness type set to MANNING (Manning's 1/n)
    • Section roughness calculated as 0.038 * (ks/1000)1/6 if channel shape Roughness type set to CW (Colebrook White)
  • New panel data is set to channel profile new panel values
• A cross section line is created at the location of each created section with section data profile values calculated using the same method as for the river sections
• The original channel link is deleted

Use the join reaches tool to merge connected reaches into a single reach.