Renavigator umgebaut

DaSaSo.ViewModel/SewerMainListViewModel.cs

@@ -65,5 +65,11 @@ namespace DaSaSo.ViewModel
             _actualProject.SetSewerObject(sewer,false);
             IsLoading = false;
         }
+
+        public override void Dispose()
+        {
+            _navigator.StateChanged -= () => OnPropertyChanged(nameof(CurrentSewerViewModel));
+            base.Dispose();
+        }
     }
 }