In order to correctly display a georeferenced layer in the Map panel, PCSWMM needs to know the coordinate system used by the layer. Setting the layer coordinate system in PCSWMM does not change the coordinates of the layer. Rather, it controls how PCSWMM interprets the coordinates of entities in the layer. Thus it is important to ensure the assigned coordinate system is correct - please consult the layer provider if unsure. Once the correct coordinate system has been assigned to the layer, it can be displayed correctly in the Map panel and/or reprojected to a more desirable coordinate system using the Reproject tool. The Map panel's map coordinate system can be different from the layer coordinate system and layers will be reprojected for display on-the-fly. For optimal performance, all layers should use a common coordinate system and the Map panel should be set to the same coordinate system.
Note that all SWMM5 layers (i.e. subcatchments, junctions,...) must use the same coordinate system.
To assign a layer's coordinate system:
In the Map panel, click on the Render button.
In the Layer Properties editor, select the desired layer from the list on the left.
The current Coordinate system for the layer is displayed near the bottom of the editor. Click on this box to open the Layer Coordinate System editor.
Select the correct coordinate system for the selected layer.
If the layer is a SWMM5 layer, a message box will prompt the user to Use this coordinate system for SWMM5 layers (all SWMM5 layers are required to have the same coordinate system).
Click on the Close button to close the Layer Properties window.