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View Full Version : Issues with Demand Allocator



JulianR
April 4, 2014, 10:22 AM
Hi, Im Infowater´s User my versión is 8.5. Actually i work in a big model and i try to allocate a demand in the junctions. I created a shapefile with the billing information, almost 350.000 points. I need assign this informatio to the model but when i run the allocate demand the work take a few minutes and dont allocate any demand. I try build the thiessen Polygons but doesnt work too. Some recomendations about? Thanks.

Shawn Huang
April 4, 2014, 11:17 AM
for 350,000 points, it will take more than one hour to complete with InfoWater 8.5. If you upgrade your InfoWater, the speed is much faster.
I think the demand allocation did not get started. Could you check if the spatial reference of the shape file is the same as your InfoWater model.

DeanCarter
July 3, 2014, 07:19 AM
I have best luck with the "closest node" method for demand allocation. Much smaller model 50K nodes with 20K service nodes (demand nodes). 30mgd system. InfoWater 10.5.2

Patrick Moore
June 30, 2015, 02:05 PM
Julian,

Thank you for posting your question here on the forum. While your answer may have already been resolved, I wanted to post a few additional considerations to think about when using the demand allocator to get the best results. It's hard to know exactly what your issue was without more details, but here are a few things that are often common causes for issues in demand allocation:

1) Check the spatial projections of the data: One thing to keep in mind when using the demand allocator is that the model assumes your meter layer and the model layers (nodes and pipes) and any Thiessen polygon layers (if used) are in the same spatial projection. If they are in different spatial projections, it is possible to lose demands when using Thiessen polygons they could fall outside of the polygons and get missed. This can be hard to realize as ArcGIS will re-project data sets so they look like they overlap, but during a spatial join (as is often done in the demand allocator) they may not line up. Any demands outside of thiessens will not load. So as a first check make sure to verify all data sets are using the same spatial projection when using the demand allocator. If they are different define the correct spatial projection for each layer using ArcToolbox or reproject the data to be in the same projection using ArcToolbox..
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2) Make sure the Demand Allocation Manager has all the key fields populated: This is Key for Meter Summation, Closest Junction or pipe, or Meter-Junction or pipe allocation methods.
There are several key fields to consider: (click for a larger image)
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2.1) Demand Field: The modeler has to select which field in the meter layer has demands. This is the "Demand Field" used by the model. The values in this field are what the model takes to be the meter demands for that point. Demands within this field should be in the same units demand is stored in the model. If the model is in US units using gpm values then the meter demand file should be in gpm units. If this is not populated correctly with demands demand will not be allocated correctly
2.2) Junction Id field (or Pipe ID field): The software assigns a junction ID (or pipe ID) to each meter when allocating demand. If there is no field to use for this the model can create a new one, but this has to be defined for the allocator to work properly. Usually this is the HX_JCT or HX_PIPE field. Without this field the model cannot sum up the demands correctly
2.3) This is where you select the meter layer to be summed up. Make sure the correct layer is identified
2.4) Check you Options for loading. The checkboxes here impact where the demand is allocated and how the model deals with existing demands. Depending on how these options were selected it is possible this could have caused demand not to be allocated especially if it was not allowed to overwrite demands. Here are the default options:(click for a larger image)
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Checking these things can often help resolve many of the common demand allocation issues faced.

Thank you,

Innovyze Support