Incorporate existing drainage system in ArcHydro Analysis

[DarrylKlassen]

Hello, I am trying to use my existing municipal drainage system (pipes, outlets, inlets, catchbasins, etc) and incorporate them in my drainage processing using ArcHydro.  How can I incorporate these features in my analysis to reflect the man-made water flow changes?   At what point of the analysis do I plug them in?  I was thinking about using the Burn Stream Slope into DEM tool and using the pipes as the input streams, but I don't know if this will accomplish what I am wanting!

Any suggestions would be appreciated.
Running ArcGIS 10.0, Python 2.6, ArcHydro 2.0

Thanks
Darryl Klassen

[MarkBoucher]

I make the pipes part of my agreestream layer (Arc Hydro term) and burn them into the DEM. In the bigger picture, this is accurate enough for me. It may cause the flow direction in some very small sub-watersheds to be inaccurate. Using the pipes to set the flow direction (Arc Hydro - Adjust flow direction in streams) is not a bad idea either. You may have to deal with flipping the polyline directions if they were not drawn from upstream to down stream. I've not done much of this.

An important concept is to not get to tied up in the importance of elevations of the DEM. The important thing is the flow direction. The burning, building walls, and filling sinks is all done to get the flow direction as close to reality as possible. Fro example, if the stream is burned 1000' into the DEM, still the flow direction will come out right.