Subnetwork Management
Hi everyone,
I am currently in the early process of deleting and updating subnetworks in our utility network. When reviewing this documentation, I run into problems at the last step. Using the water system shown below, I have removed all subnetwork controllers. Then I validate the extent and get no errors and no dirty areas display within the error inspector. Then I update the subnetwork using the find subnetwork pane or geoprocessing tool successfully. When I run the export subnetwork too, the tier parameter says that there are no clean subnetworks discovered.
Can anyone give me some guidance on how to setup a system and pressure subnetwork on the below water system? Generally speaking, the pink line pumps water from a river to a treatment plant and the pumps to distribution. Does there need to be an asset that serves as a subnetwork controller at the beginning of the pink line to represent the supply (river)? If I set the pumps at the plant as subnetwork controllers for a pressure subnetwork, all assets are assigned to the system subnetwork. Wouldn't you think that everything after the pumps would be the pressure subnetwork?
Overall, what assets do you use as subnetwork controllers within a water utility network? For example, the esri default Naperville water data uses a water treatment plant as the controller for the system subnetwork. For us, the treatment plant is an area that contains several assets which could control a subnetwork. How do you handle wells that feed a treatment plant? What about bodies of water that serve as a source for a system?
I've gone through most of the content within this documentation, but have had a difficult time applying it to our utility network. Any help regarding subnetwork management would be greatly appreciated!
- Then I update the subnetwork using the find subnetwork pane or geoprocessing tool successfully. When I run the export subnetwork too, the tier parameter says that there are no clean subnetworks discovered.
- Check your Subnetwork Definition. Do you have Manage Is Dirty set to false? If so, your subnetwork will always report Dirty and you cannot run Export Subnetwork. We typically ship the models with this set to False as there is cost managing a system tier and you need to opt into managing Is Dirty
- When I open the subnetwork table and view field details, the "ISDIRTY" field has a default value of True and the subnetwork records that I want to delete are all attributed with "True"
- MM: You need to check the Subnetwork Definition. I am pretty sure manage is dirty is set to false.
- Does there need to be an asset that serves as a subnetwork controller at the beginning of the pink line to represent the supply (river)?
- No, but you could add a intake and set it up as a controller in the system tier. This subnetwork would be a Raw water subnetwork.
- Any ideas on what type of feature or asset would represent the supply from a body of water such as a river? This is not something we have currently in our data model.
- MM: The upcoming release of the Water Utility Network Foundation, we are adding an Intake Asset Group to Water Device:
- If I set the pumps at the plant as subnetwork controllers for a pressure subnetwork, all assets are assigned to the system subnetwork. Wouldn't you think that everything after the pumps would be the pressure subnetwork?
- Yes. If you are using a pressure zone tier. I would evaluate dropping the system tier and using the Pressure Zone tier as the rank 1 tier. There is cost to managing a system tier if you just have one system.
- We have multiple independent systems within the same utility network. My thought was that each system would have a system subnetwork and then one or more multiple pressure systems. In the example I referenced, maybe the raw water line from the river would be one pressure system, and a second pressure subnetwork after treatment? How difficult is it to drop an entire system tier?
- MM: Then a system subnetwork might make sense. You could also just create them as a raw water system in the pressure zone.
- You would have to drop the system in the Asset Package. Easiest is to use the D Configuration table. https://doc.arcgis.com/en/arcgis-solutions/latest/tool-reference/utility-network-package/pdf/Utility...
- How do you handle wells that feed a treatment plant? What about bodies of water that serve as a source for a system?
- You can set wells and intakes as controllers and create a subnetwork that feeds the plant. The system tier really should not be one subnetwork
- If you have one system subnetwork, you are taking a big cost on validate. As Validate has to trace the system and if everything is one big system, that could be costly. If you plan on having a pressure zone tier, you can evaluate dropping the system tier and just using pressure zones.
- Maybe it makes more sense to split these up into separate system subnetworks for each water system? On the other hand, I'm not really sure what the purpose is for a system subnetwork. We really would like to use subnetworks as the basis for isolation, upstream, and downstream tracing. I'm thinking just having several pressure subnetworks would solve this?
- MM: If you need to trace across adjacent tiers, then having a system tiers has an advantage. When in a pressure zone, you can select system as the target tier and trace through multiple pressure zones to the treatment plant. As of 3.5 and before, you cannot trace up/down across adjacent tiers without selecting a target tier of a lower/higher rank.
Overall I would think down the road how you envision using tracing, network diagrams, network attributes, and using subnetworks for data summaries or network visualization/queries. It is up to you how you want to partition out your network for your organizations needs. It will also be important to define what you want your network controllers, terminal devices, and subnetwork barriers assets to be. You may find you need to add additional devices or even terminal connection types depending on your needs. Or even additional subnetwork tiers.
A few things to keep in mind. Currently you can only have one network controller per asset so you need to plan around that. You can however have multiple network controllers supplying the same subnetwork. Subnetworks of the same Tier can not overlap you will need to be able to isolate your subnetworks of the same Tier this can be done various ways such as terminal devices, closing valves, or altering conditional barriers on your subnetwork trace config. Subnetworks of different Tiers can overlap. For example with Esri Water Solution you can have a Water System subnetwork and Water Pressure subnetwork on the same set of assets because they are a different tier rank in the hierarchy.
For our system we moved from the Geometric Network to UN therefore at the onset we could not fully use all the potential the UN provided. We used both the UN ESRI solutions for water and sewer as our framework. For water we plan to use the Pressure and Isolation tier subnetworks in the future, however we only have the Water System subnetwork setup currently (highest level tier in the hierarchy). Water Distribution tier group hierarchy for the Esri solution from highest to lowest is Water System > Water Pressure > Water Isolation. Our utilities group still needs to define pressure nodes to isolate out pressure areas. Pressure zones would need to be defined first before that subnetwork could be setup to prevent pressure zone tier overlaps. For sewer we added an additional tier because we rely on a complex system of lift stations so we have a System, Regional, and Basin subnetwork hierarchy.
Here is a diagram of how our water treatment plant in the UN supplied by wells is setup. This uses only the Water System tier. There is a system subnetwork for the Raw water supplied by the well field, system subnetwork for the Reject water from the EDR process, and finally a system subnetwork for the potable water out after chlorine is added. You could for example also define a pressure/isolation system(s) here too you would need to have the correct set of assets to assign as controllers. In this example in the future I may represent each EDR device within the treatment plant in that case they would become the network controllers for the Reject water subnetwork. Again this comes down to how you want to represent things. In our case we had to start less complex because we don't have all the data yet to support extra detail.
Hope this helps. If you have any question please let me know. I can also provide a diagram for our sewer network if that would help.
