Index: Ringtoets/Common/src/Ringtoets.Common.Forms/Views/HydraulicBoundaryCalculationsView.cs
===================================================================
diff -u -r86a422d2f0c29eebb2c1c1efdcb3540bde62de17 -r13ee3abc211d121019b140a75e51bc9fd8acef28
--- Ringtoets/Common/src/Ringtoets.Common.Forms/Views/HydraulicBoundaryCalculationsView.cs	(.../HydraulicBoundaryCalculationsView.cs)	(revision 86a422d2f0c29eebb2c1c1efdcb3540bde62de17)
+++ Ringtoets/Common/src/Ringtoets.Common.Forms/Views/HydraulicBoundaryCalculationsView.cs	(.../HydraulicBoundaryCalculationsView.cs)	(revision 13ee3abc211d121019b140a75e51bc9fd8acef28)
@@ -39,17 +39,17 @@
     public abstract partial class HydraulicBoundaryCalculationsView : CalculationsView<HydraulicBoundaryLocationCalculation>
     {
         private readonly Observer calculationsObserver;
-        private readonly RecursiveObserver<ObservableList<HydraulicBoundaryLocationCalculation>, HydraulicBoundaryLocationCalculation> calculationObserver;
+        private readonly RecursiveObserver<IObservableEnumerable<HydraulicBoundaryLocationCalculation>, HydraulicBoundaryLocationCalculation> calculationObserver;
 
-        private readonly ObservableList<HydraulicBoundaryLocationCalculation> calculations;
+        private readonly IObservableEnumerable<HydraulicBoundaryLocationCalculation> calculations;
 
         /// <summary>
         /// Creates a new instance of <see cref="HydraulicBoundaryCalculationsView"/>.
         /// </summary>
         /// <param name="calculations">The calculations to show in the view.</param>
         /// <param name="assessmentSection">The assessment section which the calculations belong to.</param>
         /// <exception cref="ArgumentNullException">Thrown when any input parameter is <c>null</c>.</exception>
-        protected HydraulicBoundaryCalculationsView(ObservableList<HydraulicBoundaryLocationCalculation> calculations,
+        protected HydraulicBoundaryCalculationsView(IObservableEnumerable<HydraulicBoundaryLocationCalculation> calculations,
                                                     IAssessmentSection assessmentSection)
         {
             if (calculations == null)
@@ -65,7 +65,7 @@
             AssessmentSection = assessmentSection;
 
             calculationsObserver = new Observer(UpdateDataGridViewDataSource);
-            calculationObserver = new RecursiveObserver<ObservableList<HydraulicBoundaryLocationCalculation>, HydraulicBoundaryLocationCalculation>(HandleHydraulicBoundaryLocationCalculationUpdate, list => list);
+            calculationObserver = new RecursiveObserver<IObservableEnumerable<HydraulicBoundaryLocationCalculation>, HydraulicBoundaryLocationCalculation>(HandleHydraulicBoundaryLocationCalculationUpdate, hblc => hblc);
 
             this.calculations = calculations;
 
Index: Ringtoets/Common/test/Ringtoets.Common.Forms.Test/Views/HydraulicBoundaryCalculationsViewTest.cs
===================================================================
diff -u -r5bf5239188bc92fbff897b11e15a2eda6a4df337 -r13ee3abc211d121019b140a75e51bc9fd8acef28
--- Ringtoets/Common/test/Ringtoets.Common.Forms.Test/Views/HydraulicBoundaryCalculationsViewTest.cs	(.../HydraulicBoundaryCalculationsViewTest.cs)	(revision 5bf5239188bc92fbff897b11e15a2eda6a4df337)
+++ Ringtoets/Common/test/Ringtoets.Common.Forms.Test/Views/HydraulicBoundaryCalculationsViewTest.cs	(.../HydraulicBoundaryCalculationsViewTest.cs)	(revision 13ee3abc211d121019b140a75e51bc9fd8acef28)
@@ -234,7 +234,7 @@
             ShowTestHydraulicBoundaryCalculationsView(new ObservableList<HydraulicBoundaryLocationCalculation>());
         }
 
-        private TestHydraulicBoundaryCalculationsView ShowTestHydraulicBoundaryCalculationsView(ObservableList<HydraulicBoundaryLocationCalculation> calculations)
+        private TestHydraulicBoundaryCalculationsView ShowTestHydraulicBoundaryCalculationsView(IObservableEnumerable<HydraulicBoundaryLocationCalculation> calculations)
         {
             var view = new TestHydraulicBoundaryCalculationsView(calculations, new ObservableTestAssessmentSectionStub());
 
@@ -265,7 +265,7 @@
 
         private sealed class TestHydraulicBoundaryCalculationsView : HydraulicBoundaryCalculationsView
         {
-            public TestHydraulicBoundaryCalculationsView(ObservableList<HydraulicBoundaryLocationCalculation> calculations,
+            public TestHydraulicBoundaryCalculationsView(IObservableEnumerable<HydraulicBoundaryLocationCalculation> calculations,
                                                          IAssessmentSection assessmentSection)
                 : base(calculations, assessmentSection) {}