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Here’s what I am running into with Network Analyst- the goal is to create service areas for fire stations based on travel times.

• I have a baseline county wide roads shapefile that I have used as input to successfully create a network dataset and create subsequent service areas based on travel times.

• Next, I add new roads (i.e. digitize by hand) to the baseline roads dataset for a part of the county where a new housing development is going in. I am then able to create/build a network dataset without any hitches. However, when I try to create a new service area using the updated network dataset based on the updated roads shapefile, the new roads that I have added are not included/taken into account in the service area polygons that are generated. I've entered valid values for mph, length (in miles), and travel time (in minutes) for the new records.

• In short, my goal is to be able to add new roads to an existing roads shapefile and have those roads included when network analyst solves for my service area query.

• I have run the Integrate tool on the shapefile with the new roads and I still receive the same results - the new roads are not incorporated in the service area polygons that are produced.

I am fairly new to using network analyst.

  • Does integrate work on a single input layer? Or are you integrating the new roads to the old ones, then appending the records? Can you post a screenshot of your network's edge and node layers in the problem area? It sounds like you are rebuilding the network after making edits. And I assume if you're doing something with shapefiles you import whatever you change into the NDS afterward, before rebuilding, since everything has to actually be in the NDS to work. Is your connectivity policy set for any vertex or just nodes? – Chris W Apr 3 '15 at 22:37
  • I would take a look at the topology to make sure that there are no dangles or undershoots. – EikeMike Apr 4 '15 at 4:14
  • Slight correction to earlier comment - everything has to be in the same feature dataset as the NDS, not in the NDS itself. – Chris W Apr 4 '15 at 18:09
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Thanks to everyone for their help and responses and for pointing me in the right direction. When adding new roads to the baseline dataset, the key was creating the new roads and connecting them non only to one another at endpoints but also the original roads features at endpoints as well. Splitting existing roads into new lines with respective new endpoints was also key.

One additional note was that there was not an option when building the network dataset to use vertices; the only option was endpoints.

Thanks again to all for your help!

  • The option for using any vertex, rather than just endpoints, is specified in the Connectivity Policy (see resources.arcgis.com/en/help/main/10.2/index.html#/… for info on connectivity). It should have been present on one of the wizard screens for creating the network dataset, and if not you can also go into the properties of the network dataset via Catalog (window or full program) and there should be a connectivity tab there. See my answer at gis.stackexchange.com/questions/112978 for more info. – Chris W Apr 7 '15 at 0:01
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Try taking your Network with the new roads and generate a new road Network out of it. Then swap out the Networks.

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