I am trying to carry out what should be a relatively simple analysis of river network fragmentation by dams. Similar questions have been asked as:
- Obtaining length of river upstream of points up to next point using ArcGIS Desktop? and
- Finding upstream locations (polygons) using ArcGIS Geometric Network?
What I would like to achieve is:
- Calculate the distance from river outlet upstream to first dam on each river/tributary
- Calculate the cumulative number of dams from the outlet to the uppermost point
The data I am working with is:
hydrosheds 15 arc second river network. This data set includes IDs ("arcid") for numerous small segments of the polyline river network.
A point dam data set
Many answers, like a comment on Finding distance from river outlet to points, following river, using ArcGIS Desktop?, refer to a computer program, RivEX, and end there. I acknowledge the potential utility of this program, but I would like to work through the steps and run these calculations in ArcGIS Desktop.
Is creating a geometric network the right approach in this case or is there another tool that could use the built-in hydrosheds line ID and calculate distance from outlet to point (dam)?
In essence, I am unsure of how to work with the arcid field (specifying the relative position in the watershed) and represent the dams as nodes.