Index: Ringtoets/Integration/src/Ringtoets.Integration.Data/AssessmentSection.cs
===================================================================
diff -u -rf671892b6623f6561ec3752fd1a3e6344e9a2dbf -r02b7a16305179c5d4d67fe9bff0fe8b61db983e6
--- Ringtoets/Integration/src/Ringtoets.Integration.Data/AssessmentSection.cs	(.../AssessmentSection.cs)	(revision f671892b6623f6561ec3752fd1a3e6344e9a2dbf)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Data/AssessmentSection.cs	(.../AssessmentSection.cs)	(revision 02b7a16305179c5d4d67fe9bff0fe8b61db983e6)
@@ -333,8 +333,14 @@
         /// Adds hydraulic boundary location calculations for <paramref name="hydraulicBoundaryLocation"/>.
         /// </summary>
         /// <param name="hydraulicBoundaryLocation">The hydraulic boundary location to add calculations for.</param>
+        /// <exception cref="ArgumentNullException">Thrown when <paramref name="hydraulicBoundaryLocation"/> is <c>null</c>.</exception>
         public void AddHydraulicBoundaryLocationCalculations(HydraulicBoundaryLocation hydraulicBoundaryLocation)
         {
+            if (hydraulicBoundaryLocation == null)
+            {
+                throw new ArgumentNullException(nameof(hydraulicBoundaryLocation));
+            }
+
             designWaterLevelLocationCalculations1.Add(new HydraulicBoundaryLocationCalculation(hydraulicBoundaryLocation));
             designWaterLevelLocationCalculations2.Add(new HydraulicBoundaryLocationCalculation(hydraulicBoundaryLocation));
             designWaterLevelLocationCalculations3.Add(new HydraulicBoundaryLocationCalculation(hydraulicBoundaryLocation));
Index: Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/AssessmentSectionTest.cs
===================================================================
diff -u -re8353b7fea8fa71ebb78993774cf167d4faa8f1d -r02b7a16305179c5d4d67fe9bff0fe8b61db983e6
--- Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/AssessmentSectionTest.cs	(.../AssessmentSectionTest.cs)	(revision e8353b7fea8fa71ebb78993774cf167d4faa8f1d)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/AssessmentSectionTest.cs	(.../AssessmentSectionTest.cs)	(revision 02b7a16305179c5d4d67fe9bff0fe8b61db983e6)
@@ -462,6 +462,20 @@
         }
 
         [Test]
+        public void AddHydraulicBoundaryLocationCalculations_HydraulicBoundaryLocationNull_ThrowsArgumentNullException()
+        {
+            // Setup
+            var assessmentSection = new AssessmentSection(AssessmentSectionComposition.Dike);
+
+            // Call
+            TestDelegate test = () => assessmentSection.AddHydraulicBoundaryLocationCalculations(null);
+
+            // Assert
+            string paramName = Assert.Throws<ArgumentNullException>(test).ParamName;
+            Assert.AreEqual("hydraulicBoundaryLocation", paramName);
+        }
+
+        [Test]
         public void AddHydraulicBoundaryLocationCalculations_HydraulicBoundaryLocation_AddsExpectedCalculations()
         {
             // Setup