Hi all. I've just nearly completed my first GeoHMS project but ran into an issue when trying to run the "CN Lag" tool under Parameters.
Basically, the problem I ran into involved the Longest Flow Path layer. The CN Lag method expects a field in attribute table for "River" named "LongestFL" which, after running the ArcHydro Longest FP tool (for both catchments and adjoint catchments), neither shapefile has that field. The error (from ESRI.APWR.ApFramework) reads "Required/MustExist Field: LongestFL is not found - River". I tried to create a LongestFL field and feel as if I probably just made the problem worse. When I try to run the CN Lag method using the longest flow path shapefile, I get an error that states "Compute Flow Path for the Drainage Area and Try Again!".
What tool creates the flow path for the drainage area? Is there something I'm missing? I've been following Dr. Venkatesh Merwade's GeoHMS/HMS workflows, this issue is literally the last step until I can create input files for Hec-HMS.
I've downloaded the newest versions of ArcHydro and GeoHMS (I believe from 02/2013).
Has anyone else had a similar problem?
Edit: 3/13/13: I've realized I left out a very important detail. When I try to run the "Longest Flowpath" tool under the Characteristics menu, it generates a shapefile with -no- attributes. I'm really at a loss.
