Closest Downstream Facility Table

Question

Hello Everyone,

I am new to GIS and I could really use some guidance. I have been scouring the internet for hours but I just can't seem to find a good resource for what I'm trying to do.

What I have:
-Hydrologic data from the NGS which makes a network of rivers and streams. 
-Facility coordinates and testing site event points (in two different shape and table files) that I have in effect snapped to the streams using "locate feautures along routes" in linear referencing. This gave each of my events a ReachCode corresponding to the stream it's on, which is basically like an address along the stream. The higher the "address," the farther upstream the point is.

What I need to do:
Create a table that gives each facility, the testing site that's closest to it, and how far away they are from each other.

What I've tried:
I think the "make closest facility layer" will do this for me. However, I don't think I am building my network correctly. What I did was select both of my shape files for the network in new->network in ArcCatalogue. But this didn't seem to be what I thought it would be because there was nothing for me to select in the make closest facility layer field. Imagine my facilities as accidents and my testing sites as hospitals. How do I set it up so I can calculate the route distance from "accidents" to my "hospitals." I would like to use the ReachCode as a cost feature to make sure that it is giving me the closest downstream point, rather than upstream.

Please, I clearly need help.

JaySandhu · Answer

You can not build a geomeric and network dataset at the same time. So you could make a copy of the streets in a new feature dataset (in file gdb) and then right-click the feature dataset and make a network dataset.
 
I would suggest that you run through the first set of tutorials that go about making a network dataset.
 
Jay Sandhu

LaurenDahlin · Answer

Thank you so much.

This has helped me to realize my issue. I was trying to use the network analysis tool on a geometric network rather than a network dataset. Do you have any tips for how to proceed- how to in a sense convert the geometric network to a network dataset?

JaySandhu · Answer

Do you have or have you built your network dataset to do your routing on?
 
From your post:  
I don't think I am building my network correctly. What I did was select both of my shape files for the network in new->network in ArcCatalogue. But this didn't seem to be what I thought it would be because there was nothing for me to select in the make closest facility layer field.

You need to be in ArcMap, add your network dataset then from the NA toolbar create the CF layer and then you can load your locations as facilities and incidents.
 
If you have never done this then I would suggest trying out the NA tutorial:
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00470000005r000000.htm
 
Jay Sandhu