ArcHydro: Trace Downstream from Drainage Inlet

[BDAndrews]

I am trying to use a point feature class representing drainage inlets to automatically trace downstream all the connected stream segments in an ArcHydro Network. I am aware of the function ???trace downstream??? that requires a user defined start point using the blue ???add junction??? flag tool. Rather than manually select each drainage inlet of interest, I would like to use the point feature class to automatically trace downstream. Does anyone know of a function within ArcHydro that will do this?

Thanks

BD

[AbdullahBinthunaiyan]

Hi

I am working on the same thing, have you got an answer, or figured it out...

Thanks
-A

[BDAndrews]

I have not received and answer through the ArcHydro Forum. In the end I had to select (digitize) by hand the stream inlets that I wanted to trace downstream. I am still looking for a solution to my original questions because I will need to repeat it several times. If I get an answer from other resources I will post it back here.

BDA

Hi

I am working on the same thing, have you got an answer, or figured it out...

Thanks
-A

[BDAndrews]

Athenaian-

A colleague sent me the following link to a VB6 dll "Flags on Selected Junctions" on the ESRI EDN site.
http://edndoc.esri.com/arcobjects/9.2/CPP_VB6_VBA_VCPP_Doc/COM_Samples_Docs/Network/Utility_Network_...

This answered my original question. Hope it works for you as well.

BD

Hi

I am working on the same thing, have you got an answer, or figured it out...

Thanks
-A

[AaronBarkhurst]

I was not able to load this .dll into ArcInfo 10. Is there anything available for 10?

[HarryGibson]

Hello,

I just got here from google having searched for "arcgis geometric network load flags from points". Anyway a slightly different search changing the word "points" to "file" came up with this tool:
http://edndoc.esri.com/arcobjects/8.3/Samples/Network/Utility%20Network%20Analysis/Edge%20Flags%20Fr...
which although it is apparently for Arcobjects 8.3, has loaded fine into Arcmap 10, and seems to do exactly what you are looking for.

As for me I've realised that i'm better off using Network Analyst for what i'm trying to accomplish (find routes from lots of upstream points in turn to a single downstream point). This may work better for you as well if you're tracing from all source points to the river mouth. Use a Closest Facility analysis, add the mouth / downstream point as a Facility, add all your source points as Incidents, and hit solve.

Harry

[BDAndrews]

Hello Harry-

I am revisiting this problem using the solution you outlined below. I have a Hydro Network I generated using Arc Hydro (ver 1.4) and running ArcGIS 9.3 sp1. Could you please expand on the Use Closest Facility Analysis portion? I agree- that may the way to go, if I can get it to work!

Thanks
Brian

Hello,

I just got here from google having searched for "arcgis geometric network load flags from points". Anyway a slightly different search changing the word "points" to "file" came up with this tool:
http://edndoc.esri.com/arcobjects/8.3/Samples/Network/Utility%20Network%20Analysis/Edge%20Flags%20Fr...
which although it is apparently for Arcobjects 8.3, has loaded fine into Arcmap 10, and seems to do exactly what you are looking for.

As for me I've realised that i'm better off using Network Analyst for what i'm trying to accomplish (find routes from lots of upstream points in turn to a single downstream point). This may work better for you as well if you're tracing from all source points to the river mouth. Use a Closest Facility analysis, add the mouth / downstream point as a Facility, add all your source points as Incidents, and hit solve.

Harry