# Vertical Distance to Channel Network

(c) 2002 by O.Conrad
This module calculates the vertical distance to a channel network base level. The algorithm consists of two major steps:
1. Interpolation of a channel network base level elevation grid
2. Subtraction of this grid from the original elevations

## Parameters

Grid system
Grid system
  Grid system
Elevation
Input Grid
  A grid that contains elevation data.
Channel Network
Input Grid
  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.
Vertical Distance to Channel Network
Output Grid
  The resulting grid gives the altitude above the channel network in the same units as the elevation data.
Channel Network Base Level
Output Grid
  This optional grid output contains the interpolated channel network base level elevations.
Tension Threshold [m]
Floating point
Keep Base Level below Surface
Boolean