AnsweredAssumed Answered

Subwatershed Network and Drainge Lines

Question asked by on Aug 28, 2017

Hi All


I'm one of those people who knows how to get ArcHydro to do MOST of what I need, but not all.


What I want to do is to use ArcHydro to create catchments and drainage lines for input into a customised rainfall-runof modelling program.  I want it based on subwatersheds that I delineate. 


Once I have subwatersheds, I want to be able to use the existing (or make a new) Drainage Line vector feature to represent the flow paths between the sub-watersheds.  What I want to do, is to dissolve the entire drainage line network, and then split it at the subwatershed boundary. Then I want to have a from-node and to-node, which represents which "Subwatershed Point" (or Batch Point) the line goes from, and to... and then I want to populate that with Slope, 1085 slope, elevation upstream, elevation downstream etc. like the Longest flow paths are.


I then want to import all this into a rainfall-runoff modelling program, which I can do via excel sheets.  What I need for my model is

a) subwatershed outlet - easting and northing (can do)

b) subwatershed area - can do

c) subwatershed slope (I take the slope from Longest Flow Path for Subwatersheds) - can do

d) length of flow from one subwatershed outlet to another (can not do, need the method outlined above)

e) slope of flow from one subwatershed outlet to another (can not do, need the method outlined above)


Where I'm falling down is that I try to use Subwatershed and Drainage Line... and I need GRID ID features etc... it's just a constant lot of error messages because the drainge lines are not meant for this.  Anyone have any ideas?


Ideally if I could then use the Network tools to create a schematic, based on MY subwatersheds (rather than the default catchments), that would be great.