Index: Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/HeightStructuresPlugin.cs
===================================================================
diff -u -r35c2e5f60d72d56ae51a816c1cb50396f76357a4 -rbc752890b4f52991a673a59c089db400be0e6fc3
--- Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/HeightStructuresPlugin.cs	(.../HeightStructuresPlugin.cs)	(revision 35c2e5f60d72d56ae51a816c1cb50396f76357a4)
+++ Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/HeightStructuresPlugin.cs	(.../HeightStructuresPlugin.cs)	(revision bc752890b4f52991a673a59c089db400be0e6fc3)
@@ -59,6 +59,7 @@
 using Ringtoets.HeightStructures.IO;
 using Ringtoets.HeightStructures.IO.Configurations;
 using Ringtoets.HeightStructures.Plugin.FileImporters;
+using Ringtoets.HeightStructures.Plugin.Properties;
 using Ringtoets.HeightStructures.Service;
 using RingtoetsCommonFormsResources = Ringtoets.Common.Forms.Properties.Resources;
 using RingtoetsCommonDataResources = Ringtoets.Common.Data.Properties.Resources;
@@ -102,7 +103,8 @@
                 IsEnabled = IsHeightStructuresImporterEnabled,
                 FileFilterGenerator = HeightStructureFileFilter(),
                 CreateFileImporter = (context, filePath) => CreateHeightStructuresImporter(
-                    context, filePath, new ImportMessageProvider(), new HeightStructureReplaceDataStrategy(context.FailureMechanism))
+                    context, filePath, new ImportMessageProvider(), new HeightStructureReplaceDataStrategy(context.FailureMechanism)),
+                VerifyUpdates = context => VerifyHeightStructuresShouldUpdate(context, Resources.HeightStructuresPlugin_VerifyHeightStructuresShouldUpdate_When_importing_Calculation_with_Structure_data_output_will_be_cleared_confirm)
             };
 
             yield return RingtoetsImportInfoFactory.CreateCalculationConfigurationImportInfo<HeightStructuresCalculationGroupContext>(
@@ -126,7 +128,8 @@
                 FileFilterGenerator = HeightStructureFileFilter(),
                 CreateFileImporter = (context, filePath) => CreateHeightStructuresImporter(
                     context, filePath, new UpdateMessageProvider(), new HeightStructureUpdateDataStrategy(context.FailureMechanism)),
-                CurrentPath = context => context.WrappedData.SourcePath
+                CurrentPath = context => context.WrappedData.SourcePath,
+                VerifyUpdates = context => VerifyHeightStructuresShouldUpdate(context, Resources.HeightStructuresPlugin_VerifyHeightStructuresShouldUpdate_When_updating_Calculation_with_Structure_data_output_will_be_cleared_confirm)
             };
         }
 
@@ -886,6 +889,15 @@
                                            RingtoetsCommonIOResources.Shape_file_filter_Description);
         }
 
+        private bool VerifyHeightStructuresShouldUpdate(HeightStructuresContext context, string query)
+        {
+            var changeHandler = new FailureMechanismCalculationChangeHandler(context.FailureMechanism,
+                                                                             query,
+                                                                             new DialogBasedInquiryHelper(Gui.MainWindow));
+
+            return !changeHandler.RequireConfirmation() || changeHandler.InquireConfirmation();
+        }
+
         #endregion
 
         #endregion
Fisheye: Tag 183d1e7ed095ea4e8024068bc4ddfcf3ac6997d3 refers to a dead (removed) revision in file `Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/Properties/Resources.Designer.cs'.
Fisheye: No comparison available.  Pass `N' to diff?
Fisheye: Tag 183d1e7ed095ea4e8024068bc4ddfcf3ac6997d3 refers to a dead (removed) revision in file `Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/Properties/Resources.resx'.
Fisheye: No comparison available.  Pass `N' to diff?
Index: Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/Ringtoets.HeightStructures.Plugin.csproj
===================================================================
diff -u -ra8e42210f83110977d18ff743cc7b5808d2f884b -rbc752890b4f52991a673a59c089db400be0e6fc3
--- Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/Ringtoets.HeightStructures.Plugin.csproj	(.../Ringtoets.HeightStructures.Plugin.csproj)	(revision a8e42210f83110977d18ff743cc7b5808d2f884b)
+++ Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/Ringtoets.HeightStructures.Plugin.csproj	(.../Ringtoets.HeightStructures.Plugin.csproj)	(revision bc752890b4f52991a673a59c089db400be0e6fc3)
@@ -45,6 +45,11 @@
     <Compile Include="FileImporters\HeightStructureUpdateDataStrategy.cs" />
     <Compile Include="HeightStructuresPlugin.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="Properties\Resources.Designer.cs">
+      <AutoGen>True</AutoGen>
+      <DesignTime>True</DesignTime>
+      <DependentUpon>Resources.resx</DependentUpon>
+    </Compile>
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\..\..\Core\Common\src\Core.Common.Base\Core.Common.Base.csproj">
@@ -133,6 +138,12 @@
       <Link>Copying.licenseheader</Link>
     </None>
   </ItemGroup>
+  <ItemGroup>
+    <EmbeddedResource Include="Properties\Resources.resx">
+      <Generator>ResXFileCodeGenerator</Generator>
+      <LastGenOutput>Resources.Designer.cs</LastGenOutput>
+    </EmbeddedResource>
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
Index: Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/FileImporters/HeightStructureUpdateDataStrategyTest.cs
===================================================================
diff -u -rb96176ebd8a361085b738455d0882b2ab8e26ac3 -rbc752890b4f52991a673a59c089db400be0e6fc3
--- Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/FileImporters/HeightStructureUpdateDataStrategyTest.cs	(.../HeightStructureUpdateDataStrategyTest.cs)	(revision b96176ebd8a361085b738455d0882b2ab8e26ac3)
+++ Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/FileImporters/HeightStructureUpdateDataStrategyTest.cs	(.../HeightStructureUpdateDataStrategyTest.cs)	(revision bc752890b4f52991a673a59c089db400be0e6fc3)
@@ -442,7 +442,7 @@
 
             HeightStructure readAffectedStructure = new TestHeightStructure(affectedId, "New name");
             HeightStructure readUnaffectedStructure = new TestHeightStructure(unaffectedId, unaffectedStructureName);
-            
+
             // Call
             IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(targetDataCollection,
                                                                                                  new[]
@@ -460,7 +460,7 @@
             HeightStructure inputParametersUnaffectedStructure = unaffectedCalculation.InputParameters.Structure;
             Assert.AreSame(unaffectedStructure, inputParametersUnaffectedStructure);
             AssertHeightStructures(readUnaffectedStructure, inputParametersUnaffectedStructure);
-            
+
             CollectionAssert.AreEquivalent(new IObservable[]
             {
                 affectedCalculation,
@@ -470,6 +470,58 @@
         }
 
         [Test]
+        public void UpdateStructuresWithImportedData_CalculationWithSameReference_OnlyReturnsDistinctCalculation()
+        {
+            // Setup
+            const string affectedId = "affectedId";
+            var affectedStructure = new TestHeightStructure(affectedId, "Old name");
+            var affectedCalculation = new TestHeightStructuresCalculation
+            {
+                InputParameters =
+                {
+                    Structure = affectedStructure
+                },
+                Output = new TestStructuresOutput()
+            };
+
+            var failureMechanism = new HeightStructuresFailureMechanism
+            {
+                CalculationsGroup =
+                {
+                    Children =
+                    {
+                        affectedCalculation,
+                        affectedCalculation
+                    }
+                }
+            };
+
+            StructureCollection<HeightStructure> structures = failureMechanism.HeightStructures;
+            structures.AddRange(new[]
+            {
+                affectedStructure
+            }, sourceFilePath);
+
+            var structureToUpdateFrom = new TestHeightStructure(affectedId, "New name");
+
+            var strategy = new HeightStructureUpdateDataStrategy(failureMechanism);
+
+            // Call
+            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(structures,
+                                                                                                 new[]
+                                                                                                 {
+                                                                                                     structureToUpdateFrom
+                                                                                                 }, sourceFilePath);
+            // Assert
+            CollectionAssert.AreEquivalent(new IObservable[]
+            {
+                structures,
+                affectedCalculation,
+                affectedCalculation.InputParameters
+            }, affectedObjects);
+        }
+
+        [Test]
         public void UpdateStructuresWithImportedData_SectionResultWithStructureImportedStructureWithSameId_UpdatesCalculation()
         {
             // Setup
Index: Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/ImportInfos/HeightStructuresContextImportInfoTest.cs
===================================================================
diff -u -r20e9bfea15dfe132ee137283a9f24bc4c413ce4a -rbc752890b4f52991a673a59c089db400be0e6fc3
--- Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/ImportInfos/HeightStructuresContextImportInfoTest.cs	(.../HeightStructuresContextImportInfoTest.cs)	(revision 20e9bfea15dfe132ee137283a9f24bc4c413ce4a)
+++ Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/ImportInfos/HeightStructuresContextImportInfoTest.cs	(.../HeightStructuresContextImportInfoTest.cs)	(revision bc752890b4f52991a673a59c089db400be0e6fc3)
@@ -19,15 +19,22 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
 using System.Drawing;
 using System.Linq;
 using Core.Common.Base.IO;
+using Core.Common.Gui;
+using Core.Common.Gui.Forms.MainWindow;
 using Core.Common.Gui.Plugin;
 using Core.Common.TestUtil;
 using Core.Common.Utils;
+using NUnit.Extensions.Forms;
 using NUnit.Framework;
 using Rhino.Mocks;
+using Ringtoets.Common.Data;
 using Ringtoets.Common.Data.AssessmentSection;
+using Ringtoets.Common.Data.Structures;
+using Ringtoets.Common.Data.TestUtil;
 using Ringtoets.HeightStructures.Data;
 using Ringtoets.HeightStructures.Forms.PresentationObjects;
 using Ringtoets.HeightStructures.IO;
@@ -36,7 +43,7 @@
 namespace Ringtoets.HeightStructures.Plugin.Test.ImportInfos
 {
     [TestFixture]
-    public class HeightStructuresContextImportInfoTest
+    public class HeightStructuresContextImportInfoTest : NUnitFormTest
     {
         [Test]
         public void CreateFileImporter_Always_ReturnFileImporter()
@@ -183,6 +190,94 @@
             mocks.VerifyAll();
         }
 
+        [Test]
+        public void VerifyUpdates_CalculationWithoutOutputs_ReturnsTrue()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSection = mocks.Stub<IAssessmentSection>();
+            var mainWindow = mocks.Stub<IMainWindow>();
+            var gui = mocks.Stub<IGui>();
+            gui.Stub(g => g.MainWindow).Return(mainWindow);
+            mocks.ReplayAll();
+
+            using (var plugin = new HeightStructuresPlugin())
+            {
+                plugin.Gui = gui;
+
+                var failureMechanism = new HeightStructuresFailureMechanism();
+                failureMechanism.CalculationsGroup.Children.Add(new StructuresCalculation<HeightStructuresInput>());
+
+                var structures = new StructureCollection<HeightStructure>();
+                var context = new HeightStructuresContext(structures, failureMechanism, assessmentSection);
+
+                ImportInfo importInfo = GetImportInfo(plugin);
+
+                // Call
+                bool updatesVerified = importInfo.VerifyUpdates(context);
+
+                // Assert
+                Assert.IsTrue(updatesVerified);
+                mocks.VerifyAll();
+            }
+        }
+
+        [Test]
+        [TestCase(true)]
+        [TestCase(false)]
+        public void VerifyUpdates_CalculationWithOutputs_AlwaysReturnsExpectedInquiryMessage(bool isActionConfirmed)
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSection = mocks.Stub<IAssessmentSection>();
+            var mainWindow = mocks.Stub<IMainWindow>();
+            var gui = mocks.Stub<IGui>();
+            gui.Stub(g => g.MainWindow).Return(mainWindow);
+            mocks.ReplayAll();
+
+            using (var plugin = new HeightStructuresPlugin())
+            {
+                plugin.Gui = gui;
+
+                var failureMechanism = new HeightStructuresFailureMechanism();
+                failureMechanism.CalculationsGroup.Children.Add(new StructuresCalculation<HeightStructuresInput>
+                {
+                    Output = new TestStructuresOutput()
+                });
+
+                var structures = new StructureCollection<HeightStructure>();
+                var context = new HeightStructuresContext(structures, failureMechanism, assessmentSection);
+
+                ImportInfo importInfo = GetImportInfo(plugin);
+
+                string textBoxMessage = null;
+                DialogBoxHandler = (name, wnd) =>
+                {
+                    var helper = new MessageBoxTester(wnd);
+                    textBoxMessage = helper.Text;
+
+                    if (isActionConfirmed)
+                    {
+                        helper.ClickOk();
+                    }
+                    else
+                    {
+                        helper.ClickCancel();
+                    }
+                };
+
+                // Call
+                bool updatesVerified = importInfo.VerifyUpdates(context);
+
+                // Assert
+                string expectedInquiryMessage = "Als u kunstwerken importeert, dan worden alle rekenresultaten van dit toetsspoor verwijderd." +
+                                                $"{Environment.NewLine}{Environment.NewLine}Weet u zeker dat u wilt doorgaan?";
+                Assert.AreEqual(expectedInquiryMessage, textBoxMessage);
+                Assert.AreEqual(isActionConfirmed, updatesVerified);
+                mocks.VerifyAll();
+            }
+        }
+
         private static ImportInfo GetImportInfo(HeightStructuresPlugin plugin)
         {
             return plugin.GetImportInfos().First(ii => ii.DataType == typeof(HeightStructuresContext));
Index: Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/UpdateInfos/HeightStructuresContextUpdateInfoTest.cs
===================================================================
diff -u -r8e74b5d6680386fce48486c8253b62331f7d7055 -rbc752890b4f52991a673a59c089db400be0e6fc3
--- Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/UpdateInfos/HeightStructuresContextUpdateInfoTest.cs	(.../HeightStructuresContextUpdateInfoTest.cs)	(revision 8e74b5d6680386fce48486c8253b62331f7d7055)
+++ Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/UpdateInfos/HeightStructuresContextUpdateInfoTest.cs	(.../HeightStructuresContextUpdateInfoTest.cs)	(revision bc752890b4f52991a673a59c089db400be0e6fc3)
@@ -19,15 +19,21 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
 using System.Drawing;
 using System.Linq;
 using Core.Common.Base.IO;
+using Core.Common.Gui;
+using Core.Common.Gui.Forms.MainWindow;
 using Core.Common.Gui.Plugin;
 using Core.Common.TestUtil;
+using NUnit.Extensions.Forms;
 using NUnit.Framework;
 using Rhino.Mocks;
 using Ringtoets.Common.Data;
 using Ringtoets.Common.Data.AssessmentSection;
+using Ringtoets.Common.Data.Structures;
+using Ringtoets.Common.Data.TestUtil;
 using Ringtoets.HeightStructures.Data;
 using Ringtoets.HeightStructures.Forms.PresentationObjects;
 using Ringtoets.HeightStructures.IO;
@@ -36,7 +42,7 @@
 namespace Ringtoets.HeightStructures.Plugin.Test.UpdateInfos
 {
     [TestFixture]
-    public class HeightStructuresContextUpdateInfoTest
+    public class HeightStructuresContextUpdateInfoTest : NUnitFormTest
     {
         private UpdateInfo updateInfo;
         private HeightStructuresPlugin plugin;
@@ -49,7 +55,7 @@
         }
 
         [TearDown]
-        public void TearDown()
+        public override void TearDown()
         {
             plugin.Dispose();
         }
@@ -162,6 +168,85 @@
         }
 
         [Test]
+        public void VerifyUpdates_CalculationWithoutOutputs_ReturnsTrue()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSection = mocks.Stub<IAssessmentSection>();
+            var mainWindow = mocks.Stub<IMainWindow>();
+            var gui = mocks.Stub<IGui>();
+            gui.Stub(g => g.MainWindow).Return(mainWindow);
+            mocks.ReplayAll();
+
+            plugin.Gui = gui;
+
+            var failureMechanism = new HeightStructuresFailureMechanism();
+            failureMechanism.CalculationsGroup.Children.Add(new StructuresCalculation<HeightStructuresInput>());
+
+            var structures = new StructureCollection<HeightStructure>();
+            var context = new HeightStructuresContext(structures, failureMechanism, assessmentSection);
+
+            // Call
+            bool updatesVerified = updateInfo.VerifyUpdates(context);
+
+            // Assert
+            Assert.IsTrue(updatesVerified);
+            mocks.VerifyAll();
+        }
+
+        [Test]
+        [TestCase(true)]
+        [TestCase(false)]
+        public void VerifyUpdates_CalculationWithOutputs_AlwaysReturnsExpectedInquiryMessage(bool isActionConfirmed)
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSection = mocks.Stub<IAssessmentSection>();
+            var mainWindow = mocks.Stub<IMainWindow>();
+            var gui = mocks.Stub<IGui>();
+            gui.Stub(g => g.MainWindow).Return(mainWindow);
+            mocks.ReplayAll();
+
+            plugin.Gui = gui;
+
+            var failureMechanism = new HeightStructuresFailureMechanism();
+            failureMechanism.CalculationsGroup.Children.Add(new StructuresCalculation<HeightStructuresInput>
+            {
+                Output = new TestStructuresOutput()
+            });
+
+            var structures = new StructureCollection<HeightStructure>();
+            var context = new HeightStructuresContext(structures, failureMechanism, assessmentSection);
+
+            string textBoxMessage = null;
+            DialogBoxHandler = (name, wnd) =>
+            {
+                var helper = new MessageBoxTester(wnd);
+                textBoxMessage = helper.Text;
+
+                if (isActionConfirmed)
+                {
+                    helper.ClickOk();
+                }
+                else
+                {
+                    helper.ClickCancel();
+                }
+            };
+
+            // Call
+            bool updatesVerified = updateInfo.VerifyUpdates(context);
+
+            // Assert
+            string expectedInquiryMessage = "Wanneer de kunstwerken wijzigen als gevolg van het bijwerken " +
+                                            "zullen de resultaten van berekeningen die deze kunstwerken gebruiken worden verwijderd." +
+                                            $"{Environment.NewLine}{Environment.NewLine}Weet u zeker dat u wilt doorgaan?";
+            Assert.AreEqual(expectedInquiryMessage, textBoxMessage);
+            Assert.AreEqual(isActionConfirmed, updatesVerified);
+            mocks.VerifyAll();
+        }
+
+        [Test]
         public void CreateFileImporter_ValidInput_ReturnFileImporter()
         {
             // Setup