Hi @Karthi, we also have a new version of the InVEST NDR model that uses an updated routing algorithm. We don’t expect to see any more “no flow direction found…” errors from now on. If you’re interested in trying it you can find that here: https://storage.googleapis.com/releases.naturalcapitalproject.org/invest/3.6.0.post515%2Bh58c1a96ad82e/InVEST_3.6.0.post515%2Bh58c1a96ad82e_x86_Setup.exe