Utility Zones
This feature class is one of the input datasets used to create the unique cell combinations used by the WAM sub model BUCSHELL that determines the constituent loading amounts originating on source cells. Unless specified, it is assumed that a developed areas wastewater is handled by an onsite wastewater treatment system or septic tank, as specified for each land use type under Human Population. Thus, by default, wastewater is generated on the cell and would percolate into the groundwater and be delivered to the watersheds reach system. However, if a service area exists, the wastewater generated within that area would not be treated and released on the source cell, but would be transported to regional treatment centers. At the treatement center, the treated water is then possibly discharged into the reach network via a point source.
When the WAM GIS Data Geodatabase is created, an empty polygon feature class "UtilityZones" was created. This feature class contains no polygon features. After importing features into the dataset, if there are known areas that are within a wastewater service area, the ESRI ArcMap editing tools should be used to edit the spatial extent of features.
The Property Editor can be used to edit the attributes of a selected feature. When WAM is run the feature class is converted into a integer raster GRID, based on the presence of a wastewater utilities service area. Only the presence of a utility is edited with this dataset. The amount of waste generated is determined by the Land Use feature class and is characterized under Human Population.
Data Quality Assumptions
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The spatial extent of each feature polygon is accurate and there are no gaps or overlaps between polygons.
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The attribute parameterization of each feature polygon correctly defines the irrigation water source.
The required field used by the WAM Utility Zone feature class is:
| Attribute | Alias | Data Type | Scenario_WAM Join Table |
|---|---|---|---|
| UtilityZoneID | UtilityZoneID | Long Integer | Utilzone_Type.UtilzoneID |
Note that the Utility Zone feature class is joined to the Utilzone_Type table in the Scenario_WAM database on the UtilityZoneID -> Utilzone_Type.UtilzoneID field.
The UtilityZoneID values to parameterize the irrigation source are:
| SourceID | Source Type |
|---|---|
| 1 | No Utility Service |
| 2 | On Utility Service |
As with the Irrigation Source feature class, a single polygon is typically imported into this feature class and then the ArcMap editing tools are used to divide the polygon into different types after WAM setup.
To import features into the Utility Zone feature class, follow the instructions for importing data into the Irrigation Source feature class which will use the basin boundary that was created during the import of the sub-basin boundaries feature class.