Index: Ringtoets/Common/src/Ringtoets.Common.IO/Properties/Resources.Designer.cs
===================================================================
diff -u -r56a1b0ad79756583461f17301d0edcd79a1d0de4 -r1ea7670876fef947ed0481b9c19e5b26893352a6
--- Ringtoets/Common/src/Ringtoets.Common.IO/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 56a1b0ad79756583461f17301d0edcd79a1d0de4)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 1ea7670876fef947ed0481b9c19e5b26893352a6)
@@ -1038,6 +1038,16 @@
         }
         
         /// <summary>
+        ///   Looks up a localized string similar to Het importeren van kunstwerken is mislukt: {0}.
+        /// </summary>
+        public static string IStructureUpdateStrategy_UpdateStructuresWithImportedData_Importing_Structures_failed_Reason_0 {
+            get {
+                return ResourceManager.GetString("IStructureUpdateStrategy_UpdateStructuresWithImportedData_Importing_Structures_fa" +
+                        "iled_Reason_0", resourceCulture);
+            }
+        }
+        
+        /// <summary>
         ///   Looks up a localized string similar to Een gemiddelde van &apos;{0}&apos; is ongeldig voor stochast &apos;{1}&apos;..
         /// </summary>
         public static string IVariationCoefficientDistributionExtensions_TrySetMean_Mean_0_is_invalid_for_Stochast_1_ {
Index: Ringtoets/Common/src/Ringtoets.Common.IO/Properties/Resources.resx
===================================================================
diff -u -r56a1b0ad79756583461f17301d0edcd79a1d0de4 -r1ea7670876fef947ed0481b9c19e5b26893352a6
--- Ringtoets/Common/src/Ringtoets.Common.IO/Properties/Resources.resx	(.../Resources.resx)	(revision 56a1b0ad79756583461f17301d0edcd79a1d0de4)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/Properties/Resources.resx	(.../Resources.resx)	(revision 1ea7670876fef947ed0481b9c19e5b26893352a6)
@@ -643,4 +643,7 @@
   <data name="StructuresCalculationStochastAssigner_ValidateNoParametersDefined_No_structure_defined_to_add_Stochast_0" xml:space="preserve">
     <value>Er is geen kunstwerk opgegeven om de stochast '{0}' aan toe te voegen.</value>
   </data>
+  <data name="IStructureUpdateStrategy_UpdateStructuresWithImportedData_Importing_Structures_failed_Reason_0" xml:space="preserve">
+    <value>Het importeren van kunstwerken is mislukt: {0}</value>
+  </data>
 </root>
\ No newline at end of file
Index: Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/FileImporters/HeightStructureReplaceDataStrategy.cs
===================================================================
diff -u -r8b389428ece343431969fce2e902a7b241f2b372 -r1ea7670876fef947ed0481b9c19e5b26893352a6
--- Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/FileImporters/HeightStructureReplaceDataStrategy.cs	(.../HeightStructureReplaceDataStrategy.cs)	(revision 8b389428ece343431969fce2e902a7b241f2b372)
+++ Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Plugin/FileImporters/HeightStructureReplaceDataStrategy.cs	(.../HeightStructureReplaceDataStrategy.cs)	(revision 1ea7670876fef947ed0481b9c19e5b26893352a6)
@@ -26,6 +26,7 @@
 using Ringtoets.Common.Data.Exceptions;
 using Ringtoets.Common.Data.UpdateDataStrategies;
 using Ringtoets.Common.IO.Exceptions;
+using Ringtoets.Common.IO.Properties;
 using Ringtoets.Common.IO.Structures;
 using Ringtoets.HeightStructures.Data;
 using Ringtoets.HeightStructures.Service;
@@ -48,15 +49,17 @@
             : base(failureMechanism) {}
 
         public IEnumerable<IObservable> UpdateStructuresWithImportedData(StructureCollection<HeightStructure> targetDataCollection,
-                                                                         IEnumerable<HeightStructure> readStructures, string sourceFilePath)
+                                                                         IEnumerable<HeightStructure> readStructures,
+                                                                         string sourceFilePath)
         {
             try
             {
                 return ReplaceTargetCollectionWithImportedData(targetDataCollection, readStructures, sourceFilePath);
             }
             catch (UpdateDataException e)
             {
-                string message = string.Format("Het importeren van kunstwerken is mislukt: {0}", e.Message);
+                string message = string.Format(Resources.IStructureUpdateStrategy_UpdateStructuresWithImportedData_Importing_Structures_failed_Reason_0,
+                                               e.Message);
                 throw new StructureUpdateException(message, e);
             }
         }
Index: Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/FileImporters/HeightStructureReplaceDataStrategyTest.cs
===================================================================
diff -u -r8b389428ece343431969fce2e902a7b241f2b372 -r1ea7670876fef947ed0481b9c19e5b26893352a6
--- Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/FileImporters/HeightStructureReplaceDataStrategyTest.cs	(.../HeightStructureReplaceDataStrategyTest.cs)	(revision 8b389428ece343431969fce2e902a7b241f2b372)
+++ Ringtoets/HeightStructures/test/Ringtoets.HeightStructures.Plugin.Test/FileImporters/HeightStructureReplaceDataStrategyTest.cs	(.../HeightStructureReplaceDataStrategyTest.cs)	(revision 1ea7670876fef947ed0481b9c19e5b26893352a6)
@@ -23,9 +23,15 @@
 using System.Collections.Generic;
 using System.Linq;
 using Core.Common.Base;
+using Core.Common.Base.Geometry;
 using NUnit.Framework;
 using Ringtoets.Common.Data;
+using Ringtoets.Common.Data.Exceptions;
+using Ringtoets.Common.Data.FailureMechanism;
+using Ringtoets.Common.Data.Structures;
+using Ringtoets.Common.Data.TestUtil;
 using Ringtoets.Common.Data.UpdateDataStrategies;
+using Ringtoets.Common.IO.Exceptions;
 using Ringtoets.Common.IO.Structures;
 using Ringtoets.HeightStructures.Data;
 using Ringtoets.HeightStructures.Data.TestUtil;
@@ -119,9 +125,10 @@
             const string newSourcePath = "some/other/path";
 
             // Call
-            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(targetCollection,
-                                                                                                 Enumerable.Empty<HeightStructure>(),
-                                                                                                 newSourcePath);
+            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(
+                targetCollection,
+                Enumerable.Empty<HeightStructure>(),
+                newSourcePath);
 
             // Assert
             CollectionAssert.AreEqual(new IObservable[]
@@ -136,7 +143,7 @@
         public void UpdateStructuresWithImportedData_NoCurrentStructuresWithImportedData_AddsNewStructure()
         {
             // Setup
-            var importedHeightStructures = new[]
+            var importedStructures = new[]
             {
                 new TestHeightStructure()
             };
@@ -145,18 +152,188 @@
             var strategy = new HeightStructureReplaceDataStrategy(failureMechanism);
 
             // Call
-            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(failureMechanism.HeightStructures,
-                                                                                                 importedHeightStructures,
-                                                                                                 sourceFilePath);
+            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(
+                failureMechanism.HeightStructures,
+                importedStructures,
+                sourceFilePath);
 
             // Assert
             StructureCollection<HeightStructure> actualCollection = failureMechanism.HeightStructures;
-            CollectionAssert.AreEqual(importedHeightStructures, actualCollection);
+            CollectionAssert.AreEqual(importedStructures, actualCollection);
             CollectionAssert.AreEqual(new[]
             {
                 actualCollection
             }, affectedObjects);
             Assert.AreEqual(sourceFilePath, actualCollection.SourcePath);
         }
+
+        [Test]
+        public void UpdateStructuresWithImportedData_WithCurrentAndImportedDataAreDifferent_ReplacesCurrentWithImportedData()
+        {
+            // Setup
+            var failureMechanism = new HeightStructuresFailureMechanism();
+            failureMechanism.HeightStructures.AddRange(new[]
+            {
+                new TestHeightStructure("Original", "id")
+            }, sourceFilePath);
+
+            var importedStructure = new TestHeightStructure("Imported", "Different id");
+
+            var strategy = new HeightStructureReplaceDataStrategy(failureMechanism);
+
+            // Call
+            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(
+                failureMechanism.HeightStructures,
+                new[]
+                {
+                    importedStructure
+                }, sourceFilePath);
+
+            // Assert
+            CollectionAssert.AreEqual(new[]
+            {
+                failureMechanism.HeightStructures
+            }, affectedObjects);
+
+            var expected = new[]
+            {
+                importedStructure
+            };
+            CollectionAssert.AreEqual(expected, failureMechanism.HeightStructures);
+        }
+
+        [Test]
+        public void UpdateStructuresWithImportedData_CalculationWithOutputAndStructure_CalculationUpdatedAndReturnsAffectedObject()
+        {
+            // Setup
+            var structure = new TestHeightStructure();
+
+            var calculation = new StructuresCalculation<HeightStructuresInput>
+            {
+                InputParameters =
+                {
+                    Structure = structure
+                },
+                Output = new TestStructuresOutput()
+            };
+
+            var failureMechanism = new HeightStructuresFailureMechanism
+            {
+                CalculationsGroup =
+                {
+                    Children =
+                    {
+                        calculation
+                    }
+                }
+            };
+            failureMechanism.HeightStructures.AddRange(new[]
+            {
+                structure
+            }, sourceFilePath);
+
+            var strategy = new HeightStructureReplaceDataStrategy(failureMechanism);
+
+            // Call
+            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(
+                failureMechanism.HeightStructures,
+                Enumerable.Empty<HeightStructure>(),
+                sourceFilePath).ToArray();
+
+            // Assert
+            Assert.IsFalse(calculation.HasOutput);
+            Assert.IsNull(calculation.InputParameters.Structure);
+            CollectionAssert.AreEquivalent(new IObservable[]
+            {
+                calculation,
+                calculation.InputParameters,
+                failureMechanism.HeightStructures
+            }, affectedObjects);
+        }
+
+        [Test]
+        public void UpdateStructuresWithImportedData_CalculationWithSectionResultAndStructure_DataUpdatedAndReturnsAffectedObject()
+        {
+            // Setup
+            var location = new Point2D(1, 1);
+            var structure = new TestHeightStructure(location);
+
+            var calculation = new StructuresCalculation<HeightStructuresInput>
+            {
+                InputParameters =
+                {
+                    Structure = structure
+                }
+            };
+
+            var failureMechanism = new HeightStructuresFailureMechanism
+            {
+                CalculationsGroup =
+                {
+                    Children =
+                    {
+                        calculation
+                    }
+                }
+            };
+
+            failureMechanism.AddSection(new FailureMechanismSection("SectionResult", new[]
+            {
+                location
+            }));
+            HeightStructuresFailureMechanismSectionResult sectionResult = failureMechanism.SectionResults.First();
+            sectionResult.Calculation = calculation;
+
+            failureMechanism.HeightStructures.AddRange(new[]
+            {
+                structure
+            }, sourceFilePath);
+
+            var strategy = new HeightStructureReplaceDataStrategy(failureMechanism);
+
+            // Call
+            IEnumerable<IObservable> affectedObjects = strategy.UpdateStructuresWithImportedData(
+                failureMechanism.HeightStructures,
+                Enumerable.Empty<HeightStructure>(),
+                sourceFilePath).ToArray();
+
+            // Assert
+            Assert.IsNull(sectionResult.Calculation);
+            Assert.IsNull(calculation.InputParameters.Structure);
+            CollectionAssert.AreEquivalent(new IObservable[]
+            {
+                calculation.InputParameters,
+                sectionResult,
+                failureMechanism.HeightStructures
+            }, affectedObjects);
+        }
+
+        [Test]
+        public void UpdateStructuresWithImportedData_ImportedDataContainsDuplicateIds_ThrowsUpdateException()
+        {
+            // Setup
+            const string duplicateId = "I am a duplicate id";
+            HeightStructure[] importedHeightStructures =
+            {
+                new TestHeightStructure("name", duplicateId),
+                new TestHeightStructure("Other name", duplicateId)
+            };
+
+            var targetCollection = new StructureCollection<HeightStructure>();
+            var strategy = new HeightStructureReplaceDataStrategy(new HeightStructuresFailureMechanism());
+
+            // Call
+            TestDelegate call = () => strategy.UpdateStructuresWithImportedData(targetCollection,
+                                                                                importedHeightStructures,
+                                                                                sourceFilePath);
+
+            // Assert
+            var exception = Assert.Throws<StructureUpdateException>(call);
+            string expectedMessage = "Het importeren van kunstwerken is mislukt: " +
+                                     "Kunstwerken moeten een unieke id hebben. " +
+                                     $"Gevonden dubbele elementen: {duplicateId}.";
+            Assert.AreEqual(expectedMessage, exception.Message);
+            Assert.IsInstanceOf<UpdateDataException>(exception.InnerException);
+        }
     }
 }
\ No newline at end of file