How can you move an element when working with a model in the ArcGIS environment?
In order to move an element when you are working in WaterGEMS for ArcGIS or SewerGEMS for ArcGIS, you have to use the ArcMap Edit tool, as shown in the following screenshot.
There is a selection tool in the WaterGEMS/SewerGEMS toolbar, but this is only related to selecting elements to view properties. The ArcMap Edit tool will allow you to move objects. You will also need to be in an editing session.
WaterGEMS for ArcGIS [FAQ]