Data Managers need to be aware of these considerations while working with Management Requirement (MR) shapes:
There are no formal data standards for Management Requirement (MR) shapes. Each shapefile uploaded represents the spatial area for a single management requirement. MR shapes must be polygons. If you wish to represent a management requirement as a line or point, you'll need to buffer them into a polygon before attempting to use them as an MR shape.
If the incoming shapefile has multiple records, WFDSS dissolves them into a single polygon. Attributes in the shapefile are ignored; the Management Requirement label and description are entered into the WFDSS Data Management/Unit Shapes tab when the MR shapefile is uploaded. If you wish to load multiple MRs, you must load them one shapefile at a time.
There is a 150,000-vertex limit for MR shapes. It is important to consider that for shapes that extend beyond the unit boundary. By default, WFDSS clips MR shapes to unit boundaries. This step ensures that you do not have any Management Requirements that apply outside your area. This can result in a fairly simple MR shape gaining significant complexity when the unit boundary is complex in the area where the clip occurred. For example, a shape with 129K vertices could bounce back with a message telling you that there were 150K vertices. Pay attention to the error messages you get if an MR shape fails to load. It will often mention that a clip occurred and there was a violation of the vertex limit.
Here are some tips for dealing with complex MR shapes:
You can count the vertices in your MR shape in ArcGIS by adding a Double field called "VertCnt" and calculating its value with the FieldCalculator Python expression: !shape!.pointcount. Make sure the Python Parser radio button is selected.
Here are some tips for dealing with MR shapes that become unwieldy due to the boundary clipping issue.
The current vertex limit for Management Requirements is 150K. You can count the vertices in your upload shape in ArcGIS by adding a Double field called "VertCnt" and calculating its value with the FieldCalculator Python expression: !shape!.pointcount Make sure the Python Parser radio button is selected.
You can 'thin" a shape's vertices with the Simplify Polygon tool to get it under the limit.
WFDSS clips the Management Requirement shape with the Unit boundary (all the FMU/SO shapes for that unit merged). This step ensures that you do not have management requirements that apply outside your unit, and is therefore necessary. If you have a complex boundary, that can add many vertices, so a shape under the limit does not guarantee success. (For example, a shape with 129K vertices could bounce back with bounce with a message telling you that there were 150K vertices.)
If you hit the limit try one or more of the following:
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