Index: Ringtoets/Piping/src/Ringtoets.Piping.Forms/PropertyClasses/PipingInputContextProperties.cs
===================================================================
diff -u -r428346aca4810ed68d8778943246f581cb1a4386 -rbe8c50b3fa0529fda1fe17ddeae50055f958a0bd
--- Ringtoets/Piping/src/Ringtoets.Piping.Forms/PropertyClasses/PipingInputContextProperties.cs	(.../PipingInputContextProperties.cs)	(revision 428346aca4810ed68d8778943246f581cb1a4386)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Forms/PropertyClasses/PipingInputContextProperties.cs	(.../PipingInputContextProperties.cs)	(revision be8c50b3fa0529fda1fe17ddeae50055f958a0bd)
@@ -201,7 +201,13 @@
             }
             set
             {
+                if (double.IsNaN(value.DesignWaterLevel))
+                {
+                    string message = string.Format(Resources.PipingInputContextProperties_HydraulicBoundaryLocation_No_design_water_level_calculated, value.Name);
+                    throw new ArgumentException(message);
+                }
                 data.WrappedData.HydraulicBoundaryLocation = value;
+                data.WrappedData.AssessmentLevel = value.DesignWaterLevel;
                 data.WrappedData.NotifyObservers();
             }
         }