Index: Ringtoets/Piping/src/Ringtoets.Piping.Data/DerivedPipingInput.cs
===================================================================
diff -u -r420c266df87245b9471d3794ef5043ee89cb482a -r16b01f208966fa77f73b7977db23da94786f08d1
--- Ringtoets/Piping/src/Ringtoets.Piping.Data/DerivedPipingInput.cs	(.../DerivedPipingInput.cs)	(revision 420c266df87245b9471d3794ef5043ee89cb482a)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Data/DerivedPipingInput.cs	(.../DerivedPipingInput.cs)	(revision 16b01f208966fa77f73b7977db23da94786f08d1)
@@ -21,10 +21,8 @@
 
 using System;
 using Core.Common.Base.Data;
-using log4net;
 using Ringtoets.HydraRing.Data;
 using Ringtoets.Piping.Data.Probabilistics;
-using Ringtoets.Piping.Data.Properties;
 using Ringtoets.Piping.InputParameterCalculation;
 using Ringtoets.Piping.Primitives;
 
@@ -36,7 +34,6 @@
     public class DerivedPipingInput
     {
         private const double seepageLengthStandardDeviationFraction = 0.1;
-        private static readonly ILog log = LogManager.GetLogger(typeof(DerivedPipingInput));
 
         private readonly PipingInput input;
 
Index: Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingInput.cs
===================================================================
diff -u -r420c266df87245b9471d3794ef5043ee89cb482a -r16b01f208966fa77f73b7977db23da94786f08d1
--- Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingInput.cs	(.../PipingInput.cs)	(revision 420c266df87245b9471d3794ef5043ee89cb482a)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingInput.cs	(.../PipingInput.cs)	(revision 16b01f208966fa77f73b7977db23da94786f08d1)
@@ -40,16 +40,11 @@
         private readonly GeneralPipingInput generalInputParameters;
         private readonly NormalDistribution phreaticLevelExit;
         private readonly LognormalDistribution dampingFactorExit;
-        private readonly LognormalDistribution thicknessCoverageLayer;
         private readonly ShiftedLognormalDistribution saturatedVolumicWeightOfCoverageLayer;
-        private readonly LognormalDistribution thicknessAquiferLayer;
         private readonly LognormalDistribution darcyPermeability;
         private readonly LognormalDistribution diameter70;
-        private readonly LognormalDistribution seepageLength;
-        private RoundedDouble assessmentLevel;
         private RoundedDouble exitPointL;
         private RoundedDouble entryPointL;
-        private RoundedDouble piezometricHeadExit;
         private RingtoetsPipingSurfaceLine surfaceLine;
 
         private PipingSoilProfile soilProfile;
@@ -73,38 +68,21 @@
 
             exitPointL = new RoundedDouble(2, double.NaN);
             entryPointL = new RoundedDouble(2, double.NaN);
-            assessmentLevel = new RoundedDouble(2, double.NaN);
-            piezometricHeadExit = new RoundedDouble(2, double.NaN);
 
             phreaticLevelExit = new NormalDistribution(3);
             dampingFactorExit = new LognormalDistribution(3)
             {
                 Mean = (RoundedDouble) 0.7,
                 StandardDeviation = (RoundedDouble) 0.0
             };
-            thicknessCoverageLayer = new LognormalDistribution(2)
-            {
-                Mean = (RoundedDouble) double.NaN,
-                StandardDeviation = (RoundedDouble) 0.5
-            };
             saturatedVolumicWeightOfCoverageLayer = new ShiftedLognormalDistribution(2)
             {
                 Shift = (RoundedDouble) 10,
                 Mean = (RoundedDouble) 17.5,
                 StandardDeviation = (RoundedDouble) 0
             };
-            seepageLength = new LognormalDistribution(2)
-            {
-                Mean = (RoundedDouble) double.NaN,
-                StandardDeviation = (RoundedDouble) double.NaN
-            };
             diameter70 = new LognormalDistribution(2);
             darcyPermeability = new LognormalDistribution(3);
-            thicknessAquiferLayer = new LognormalDistribution(2)
-            {
-                Mean = (RoundedDouble) double.NaN,
-                StandardDeviation = (RoundedDouble) 0.5
-            };
         }
 
         /// <summary>
Index: Ringtoets/Piping/src/Ringtoets.Piping.Forms/PropertyClasses/PipingInputContextProperties.cs
===================================================================
diff -u -r43fb77c51a8d1c0af128a2da0c3d51bbea6e25bb -r16b01f208966fa77f73b7977db23da94786f08d1
--- Ringtoets/Piping/src/Ringtoets.Piping.Forms/PropertyClasses/PipingInputContextProperties.cs	(.../PipingInputContextProperties.cs)	(revision 43fb77c51a8d1c0af128a2da0c3d51bbea6e25bb)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Forms/PropertyClasses/PipingInputContextProperties.cs	(.../PipingInputContextProperties.cs)	(revision 16b01f208966fa77f73b7977db23da94786f08d1)
@@ -160,8 +160,12 @@
             }
             set
             {
-                data.WrappedData.SurfaceLine = value;
-                data.WrappedData.NotifyObservers();
+                if (!ReferenceEquals(value, data.WrappedData.SurfaceLine))
+                {
+                    data.WrappedData.SurfaceLine = value;
+                    data.WrappedData.SoilProfile = null;
+                    data.WrappedData.NotifyObservers();
+                }
             }
         }
 
Index: Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PresentationObjects/PipingInputContextTest.cs
===================================================================
diff -u -r43fb77c51a8d1c0af128a2da0c3d51bbea6e25bb -r16b01f208966fa77f73b7977db23da94786f08d1
--- Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PresentationObjects/PipingInputContextTest.cs	(.../PipingInputContextTest.cs)	(revision 43fb77c51a8d1c0af128a2da0c3d51bbea6e25bb)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PresentationObjects/PipingInputContextTest.cs	(.../PipingInputContextTest.cs)	(revision 16b01f208966fa77f73b7977db23da94786f08d1)
@@ -10,7 +10,6 @@
 using Ringtoets.Piping.Data;
 using Ringtoets.Piping.Data.TestUtil;
 using Ringtoets.Piping.Forms.PresentationObjects;
-using Ringtoets.Piping.KernelWrapper.TestUtil;
 using Ringtoets.Piping.Primitives;
 
 namespace Ringtoets.Piping.Forms.Test.PresentationObjects
Index: Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PropertyClasses/PipingInputContextPropertiesTest.cs
===================================================================
diff -u -r43fb77c51a8d1c0af128a2da0c3d51bbea6e25bb -r16b01f208966fa77f73b7977db23da94786f08d1
--- Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PropertyClasses/PipingInputContextPropertiesTest.cs	(.../PipingInputContextPropertiesTest.cs)	(revision 43fb77c51a8d1c0af128a2da0c3d51bbea6e25bb)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PropertyClasses/PipingInputContextPropertiesTest.cs	(.../PipingInputContextPropertiesTest.cs)	(revision 16b01f208966fa77f73b7977db23da94786f08d1)
@@ -435,6 +435,92 @@
         }
 
         [Test]
+        public void SurfaceLine_NewSurfaceLine_SoilProfileSetToNull()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSectionMock = mocks.StrictMock<AssessmentSectionBase>();
+            mocks.ReplayAll();
+
+            var inputParameters = new PipingInput(new GeneralPipingInput());
+            var properties = new PipingInputContextProperties
+            {
+                Data = new PipingInputContext(inputParameters,
+                                              Enumerable.Empty<RingtoetsPipingSurfaceLine>(),
+                                              Enumerable.Empty<StochasticSoilModel>(),
+                                              assessmentSectionMock)
+            };
+            inputParameters.SoilProfile = new TestPipingSoilProfile();
+
+            // Call
+            properties.SurfaceLine = ValidSurfaceLine(0, 2);
+
+            // Assert
+            Assert.IsNull(inputParameters.SoilProfile);
+        }
+
+        [Test]
+        public void SurfaceLine_SameSurfaceLine_SoilProfileUnchanged()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSectionMock = mocks.StrictMock<AssessmentSectionBase>();
+            mocks.ReplayAll();
+
+            var testSurfaceLine = ValidSurfaceLine(0, 2);
+            var testPipingSoilProfile = new TestPipingSoilProfile();
+
+            var inputParameters = new PipingInput(new GeneralPipingInput())
+            {
+                SurfaceLine = testSurfaceLine,
+                SoilProfile = testPipingSoilProfile
+            };
+            var properties = new PipingInputContextProperties
+            {
+                Data = new PipingInputContext(inputParameters,
+                                              Enumerable.Empty<RingtoetsPipingSurfaceLine>(),
+                                              Enumerable.Empty<StochasticSoilModel>(),
+                                              assessmentSectionMock)
+            };
+
+            // Call
+            properties.SurfaceLine = testSurfaceLine;
+
+            // Assert
+            Assert.AreSame(testPipingSoilProfile, inputParameters.SoilProfile);
+        }
+
+        [Test]
+        public void SurfaceLine_DifferentSurfaceLine_SoilProfileSetToNull()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSectionMock = mocks.StrictMock<AssessmentSectionBase>();
+            mocks.ReplayAll();
+
+            var testPipingSoilProfile = new TestPipingSoilProfile();
+
+            var inputParameters = new PipingInput(new GeneralPipingInput())
+            {
+                SurfaceLine = ValidSurfaceLine(0, 2),
+                SoilProfile = testPipingSoilProfile
+            };
+            var properties = new PipingInputContextProperties
+            {
+                Data = new PipingInputContext(inputParameters,
+                                              Enumerable.Empty<RingtoetsPipingSurfaceLine>(),
+                                              Enumerable.Empty<StochasticSoilModel>(),
+                                              assessmentSectionMock)
+            };
+
+            // Call
+            properties.SurfaceLine = ValidSurfaceLine(0, 2);
+
+            // Assert
+            Assert.IsNull(inputParameters.SoilProfile);
+        }
+
+        [Test]
         [TestCase(1)]
         [TestCase(2)]
         public void GivenCompletePipingInputContextProperties_WhenPhreaticLevelExitPropertiesSetThroughProperties_ThenPiezometricHeadExitUpdated(int propertyIndexToChange)