Once the Usage Table is populated, define the method used to allocate junction node demands.
- Defines the method used to allocate junction node demands. The different methods are explained below:
Polygon Intersection - This method uses spatial intersection of a demand class/classification categorization polygon with demand area polygon coverage to determine the nodal demand allocation. The primary layer represents the demand (service) area polygon and the secondary layer represents the demand categorization polygon as shown below.
Polygon Extraction - This method is used when an intersected polygon coverage has already been established and imported into InfoWater Pro Allocator.
Meter Summation - This method is used when customer billing data is available. The primary layer represents the demand (service) area polygon coverage.
Additionally the meter configuration data needs to be specified as well.
When using consumer/meter data to estimate nodal demands, this data must first be configured. The Demand Field represents the field that contains the demand at each of the consumer meters. The Usage Type Field designates the field that contains the water duty type data. The Meter Layer specifies the desired consumer/meter layer.
This method is used when customer/meter-billing data is available. The meter layer needs to be configured. The Demand Field and Usage Type Field contain demand and water duty data at each of the meters.
Additionally, you are able to select which junctions will be considered for the closest junction method by using the Apply to Junctions in Domain check box at the bottom of the Demand Allocation Manager dialog box.
This method also works with customer-billing data and requires meter configuration. The Demand Field and Usage Type Field contain demand and water duty data at each of the meters.
It is important to note that when the closest pipe method is selected, the following options become available to you.
Use this option when you only wish to consider allocating meter demands to pipes that are in the current active domain.
During the closest pipe allocation process, you have the option of specifying how meter demands are to be allocated to the upstream and downstream junctions of a pipe. Those options are as follows:
Evenly Divided - The total demands determined from all meters assigned to a particular pipe will be divided by 2 and assigned equally to both the upstream and downstream junctions of the pipe.
Distance Weighted - A geometric analysis is conducted for each meter assigned. Demands are then divided between two junction nodes according to their weighting. For example, if a meter has 10 gpm and is 3/4 way down a pipe, 1/4 of 10 gpm will go to one junction while 3/4 of 10 gpm will go to the other.
Closest Junction - Meters closest to one end of pipe will be allocated to the junction closest to them.
Furthest Junction - Opposite of closest junction, closest meters will be assigned to the furthest junction node. When using consumer/meter data to estimate nodal demands, this data must first be configured. The Demand Field represents the field that contains the demand at each of the consumer meters. The Usage Type Field designates the field that contains the water duty type data. The Meter Layer specifies the desired consumer/meter layer.
This method is similar to the closest junction method, except you are able to assign which meters will be allocated to which junction nodes. In other words, it is a user-defined version of the closest junction method (which generates meter demands automatically). In order for the meter-junction method to be employed, you must specify which fields possess (or will possess) the junction ID's. Specify which field contains (or will contain) the junction ID in the Junction ID Field drop-down box for each meter in the system. Use the New Field button to create a new field for a meter associated with a junction. Use the Purge IDs button to reset all the IDs for meters associated with junctions.
This method is similar to the closest pipe method, except you are able to assign which meters will be allocated to which pipes. In other words, it is a user-defined version of the closest pipe method (which generates meter demands automatically). In order for the meter-pipe method to be employed, you must specify which fields possess (or will possess) the pipe ID's. Specify which field contains (or will contain) the pipe ID using the Pipe ID Field drop-down box for each meter in the system. Use the New Field button to create a new field for a meter associated with a pipe. Use the Purge IDs button to reset all the IDs for meters associated with pipes.
All options available in the Closest Pipe methodology are also available in the Meter-Pipe Allocation method.
Normalize demand data. The default value is set to unity (1.0) in the field and it may be changed to reflect the actual demand multiplier.