Index: DamEngine/trunk/src/Deltares.DamEngine.Interface/EngineInterface.cs
===================================================================
diff -u -r4540 -r5426
--- DamEngine/trunk/src/Deltares.DamEngine.Interface/EngineInterface.cs	(.../EngineInterface.cs)	(revision 4540)
+++ DamEngine/trunk/src/Deltares.DamEngine.Interface/EngineInterface.cs	(.../EngineInterface.cs)	(revision 5426)
@@ -105,7 +105,9 @@
 
         try
         {
-            DamProjectData.Dike.Validate(DamProjectData.DamProjectType == DamProjectType.Operational);
+            bool isOperational = DamProjectData.DamProjectType == DamProjectType.Operational;
+            bool isPiping = DamProjectData.DamProjectCalculationSpecification.CurrentSpecification.FailureMechanismSystemType == FailureMechanismSystemType.Piping;
+            DamProjectData.Dike.Validate(isOperational, isPiping);
         }
         catch (Exception e)
         {