Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators/DikesDesign/DesignCalculatorCombinedSlopeAndShoulderAdaption.cs
===================================================================
diff -u -r4540 -r5471
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators/DikesDesign/DesignCalculatorCombinedSlopeAndShoulderAdaption.cs	(.../DesignCalculatorCombinedSlopeAndShoulderAdaption.cs)	(revision 4540)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators/DikesDesign/DesignCalculatorCombinedSlopeAndShoulderAdaption.cs	(.../DesignCalculatorCombinedSlopeAndShoulderAdaption.cs)	(revision 5471)
@@ -24,6 +24,7 @@
 using System.Linq;
 using Deltares.DamEngine.Calculators.KernelWrappers.Common;
 using Deltares.DamEngine.Calculators.KernelWrappers.Interfaces;
+using Deltares.DamEngine.Calculators.KernelWrappers.MacroStabilityCommon;
 using Deltares.DamEngine.Calculators.Properties;
 using Deltares.DamEngine.Data.Design;
 using Deltares.DamEngine.Data.General;
@@ -90,7 +91,7 @@
             location.AlignBoundaryPointsOfPl1LineWithAdaptedSurfaceLine(surfaceLine);
             List<LogMessage> locationCalculationMessages;
             DesignCalculatorUtils.KernelCalculate(out kernelDataInput, kernelWrapper, out kernelDataOutput, damKernelInput,
-                                                  iterationIndex, out locationCalculationMessages);
+                                                                                                   iterationIndex, out locationCalculationMessages);
             calculationMessages.AddRange(locationCalculationMessages);
             DesignAdvise designAdvise;
             string evaluationMessage;
@@ -107,8 +108,12 @@
                 double maxFractionOfDikeHeightForShoulderHeight = location.UseNewMaxHeightShoulderAsFraction ? location.NewMaxHeightShoulderAsFraction : defaultMaxFractionOfDikeHeightForShoulderHeight;
                 double maxShoulderLevel = DesignCalculatorUtils.CalculateMaximumShoulderLevel(surfaceLine,
                                                                                               maxFractionOfDikeHeightForShoulderHeight);
+                var orgSoilProfile2D = damKernelInput.SubSoilScenario.SoilProfile2D.Clone();
+                damKernelInput.CurrentEmbankmentSoil = location.GetDikeEmbankmentSoil();
                 while (isRedesignRequired && surfaceLine != null)
                 {
+                    // Always start with the original soil profile
+                    damKernelInput.SubSoilScenario.SoilProfile2D = orgSoilProfile2D;
                     iterationIndex++;
                     DesignCalculatorUtils.ThrowWhenMaxIterationsExceeded(iterationIndex, maxRedesignIterations);
 
@@ -169,7 +174,7 @@
                         Soil embankmentSoil =
                             location.SoilList.GetSoilByName(embankmentDesignParameters.EmbankmentMaterialname);
                         subSoilScenario.SoilProfile2D =
-                            AdaptProfile2DToNewSurfaceLine(subSoilScenario.SoilProfile2D, surfaceLine, embankmentSoil);
+                            MacroStabilityCommonHelper.CombineSoilProfileWithSurfaceLine(subSoilScenario, surfaceLine, embankmentSoil);
                     }
 
                     DesignCalculatorUtils.KernelCalculate(out kernelDataInput, kernelWrapper, out kernelDataOutput, damKernelInput,
@@ -205,32 +210,4 @@
             throw new DesignCalculatorException(Resources.DesignUnsuccessful + " " + errorMessage);
         }
     }
-
-    private static SoilProfile2D AdaptProfile2DToNewSurfaceLine(SoilProfile2D soilProfile2D, SurfaceLine2 surfaceLine, Soil dikeEmbankmentSoil)
-    {
-        double topX = surfaceLine.CharacteristicPoints.GetGeometryPoint(CharacteristicPointType.DikeTopAtPolder).X;
-        SoilProfile1D soilProfile1D = soilProfile2D.GetSoilProfile1D(topX);
-        var soilSurfaceProfile = new SoilSurfaceProfile
-        {
-            SoilProfile = soilProfile1D,
-            SurfaceLine2 = surfaceLine,
-            Name = soilProfile2D.Name,
-            DikeEmbankmentMaterial = dikeEmbankmentSoil
-        };
-        // Convert the soilSurfaceProfile to a SoilProfile2D to be able to edit it properly.
-        SoilProfile2D soilProfile2DNew = soilSurfaceProfile.ConvertToSoilProfile2D();
-        int numberOfCommonSurface = Math.Min(soilProfile2DNew.Surfaces.Count, soilProfile2D.Surfaces.Count);
-        for (var i = 0; i < numberOfCommonSurface; i++)
-        {
-            soilProfile2DNew.Surfaces[i].WaterpressureInterpolationModel =
-                soilProfile2D.Surfaces[i].WaterpressureInterpolationModel;
-        }
-
-        for (int i = numberOfCommonSurface; i < soilProfile2DNew.Surfaces.Count; i++)
-        {
-            soilProfile2DNew.Surfaces[i].WaterpressureInterpolationModel = WaterpressureInterpolationModel.Automatic;
-        }
-
-        return soilProfile2DNew;
-    }
 }
\ No newline at end of file
Index: DamEngine/trunk/src/Deltares.DamEngine.IntegrationTests/IntegrationTests/MacroStabilityInwardsTests.cs
===================================================================
diff -u -r5466 -r5471
--- DamEngine/trunk/src/Deltares.DamEngine.IntegrationTests/IntegrationTests/MacroStabilityInwardsTests.cs	(.../MacroStabilityInwardsTests.cs)	(revision 5466)
+++ DamEngine/trunk/src/Deltares.DamEngine.IntegrationTests/IntegrationTests/MacroStabilityInwardsTests.cs	(.../MacroStabilityInwardsTests.cs)	(revision 5471)
@@ -487,7 +487,7 @@
     }
 
     [TestCase("SlopeAdaptionBeforeShoulderAdaption", 1.4, 1.515, 5)]
-    [TestCase("OptimizedSlopeAndShoulderAdaption", 1.4, 1.426, 3)]
+    [TestCase("OptimizedSlopeAndShoulderAdaption", 1.4, 1.581, 4)]
     public void GivenTutorialDesignDwp1_WhenRunWithGeometryAdaption_ThenGivesExpectedResults(string designMethod,
         double requiredSafetyFactor, double actualSafetyFactor, int iterationCount)
     {