Index: Ringtoets/Common/src/Ringtoets.Common.Data/Hydraulics/HydraulicBoundaryLocationCalculation.cs
===================================================================
diff -u -re66b3793a9cdea90b0c2665111d7ddc135ddc41e -r1026dd2d5cef03cffca2f390ef5e7ce0a07e33dd
--- Ringtoets/Common/src/Ringtoets.Common.Data/Hydraulics/HydraulicBoundaryLocationCalculation.cs	(.../HydraulicBoundaryLocationCalculation.cs)	(revision e66b3793a9cdea90b0c2665111d7ddc135ddc41e)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/Hydraulics/HydraulicBoundaryLocationCalculation.cs	(.../HydraulicBoundaryLocationCalculation.cs)	(revision 1026dd2d5cef03cffca2f390ef5e7ce0a07e33dd)
@@ -20,13 +20,14 @@
 // All rights reserved.
 
 using System;
+using Core.Common.Base;
 
 namespace Ringtoets.Common.Data.Hydraulics
 {
     /// <summary>
     /// This class holds information about a calculation for a hydraulic boundary location.
     /// </summary>
-    public class HydraulicBoundaryLocationCalculation
+    public class HydraulicBoundaryLocationCalculation : Observable
     {
         /// <summary>
         /// Creates a new instance of <see cref="HydraulicBoundaryLocationCalculation"/>.
Index: Ringtoets/Common/test/Ringtoets.Common.Data.Test/Hydraulics/HydraulicBoundaryLocationCalculationTest.cs
===================================================================
diff -u -rbe503a934e5872a244369c7ef25b043c6e0c614f -r1026dd2d5cef03cffca2f390ef5e7ce0a07e33dd
--- Ringtoets/Common/test/Ringtoets.Common.Data.Test/Hydraulics/HydraulicBoundaryLocationCalculationTest.cs	(.../HydraulicBoundaryLocationCalculationTest.cs)	(revision be503a934e5872a244369c7ef25b043c6e0c614f)
+++ Ringtoets/Common/test/Ringtoets.Common.Data.Test/Hydraulics/HydraulicBoundaryLocationCalculationTest.cs	(.../HydraulicBoundaryLocationCalculationTest.cs)	(revision 1026dd2d5cef03cffca2f390ef5e7ce0a07e33dd)
@@ -21,6 +21,7 @@
 
 using System;
 using System.Collections.Generic;
+using Core.Common.Base;
 using NUnit.Framework;
 using Ringtoets.Common.Data.Hydraulics;
 using Ringtoets.Common.Data.TestUtil;
@@ -52,8 +53,9 @@
             var calculation = new HydraulicBoundaryLocationCalculation(hydraulicBoundaryLocation);
 
             // Assert
+            Assert.IsInstanceOf<Observable>(calculation);
             Assert.AreSame(hydraulicBoundaryLocation, calculation.HydraulicBoundaryLocation);
-            Assert.IsInstanceOf<HydraulicBoundaryLocationCalculationInput>(calculation.InputParameters);
+            Assert.IsNotNull(calculation.InputParameters);
             Assert.IsNull(calculation.Output);
         }