Index: Ringtoets/DuneErosion/src/Ringtoets.DuneErosion.Data/DuneLocationCalculation.cs
===================================================================
diff -u -rf515fbd73e83548678552ed9e637957e1db0a3d0 -rbae137524febd2b8418ea3ceb47a6330d3c53c1e
--- Ringtoets/DuneErosion/src/Ringtoets.DuneErosion.Data/DuneLocationCalculation.cs	(.../DuneLocationCalculation.cs)	(revision f515fbd73e83548678552ed9e637957e1db0a3d0)
+++ Ringtoets/DuneErosion/src/Ringtoets.DuneErosion.Data/DuneLocationCalculation.cs	(.../DuneLocationCalculation.cs)	(revision bae137524febd2b8418ea3ceb47a6330d3c53c1e)
@@ -21,13 +21,14 @@
 
 using System;
 using Core.Common.Base;
+using Ringtoets.Common.Data.Calculation;
 
 namespace Ringtoets.DuneErosion.Data
 {
     /// <summary>
     /// Adapter class for a dune location calculation.
     /// </summary>
-    public class DuneLocationCalculation : Observable
+    public class DuneLocationCalculation : Observable, ICalculatable
     {
         /// <summary>
         /// Creates a new instance of <see cref="DuneLocationCalculation"/>.
@@ -54,5 +55,13 @@
         /// Gets the dune location the calculation belongs to.
         /// </summary>
         public DuneLocation DuneLocation { get; }
+
+        public bool ShouldCalculate
+        {
+            get
+            {
+                return Output == null;
+            }
+        }
     }
 }
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