Index: DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/SoilProfile2DSurfaceLineHelperTests.cs
===================================================================
diff -u -r6404 -r7040
--- DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/SoilProfile2DSurfaceLineHelperTests.cs	(.../SoilProfile2DSurfaceLineHelperTests.cs)	(revision 6404)
+++ DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/SoilProfile2DSurfaceLineHelperTests.cs	(.../SoilProfile2DSurfaceLineHelperTests.cs)	(revision 7040)
@@ -129,19 +129,7 @@
                     ExpectedSurfaceCount = 9,
                     // 3 extra surfaces created: 1 below the "zigzag" surface line + 2 on the left side (between Z=60 and 70)
                     ExpectedFilling1 = FactoryForSoilProfiles.CreatePolygoneSoilLayer2D([
-                        ..new[]
-                        {
-                            new Point2D(-50, 13),
-                            new Point2D(-30, 15),
-                            new Point2D(10, 11),
-                            new Point2D(50, 15),
-                            new Point2D(70, 13),
-                            new Point2D(70, 10),
-                            new Point2D(60, 10),
-                            new Point2D(0, 10),
-                            new Point2D(-20, 10),
-                            new Point2D(-50, 10)
-                        }
+                        new Point2D(-50, 13), new Point2D(-30, 15), new Point2D(10, 11), new Point2D(50, 15), new Point2D(70, 13), new Point2D(70, 10), new Point2D(60, 10), new Point2D(0, 10), new Point2D(-20, 10), new Point2D(-50, 10)
                     ], soilFilling, newSoilProfile2D),
                     ExpectedFilling2 = null,
                     ExpectedExtendedSurface1 = null,
@@ -469,6 +457,44 @@
         }
     }
 
+    [Test]
+    public void GivenSoilProfile2DWithASurfacePointCoincidingWithEndPointOfSurfaceLine_WhenCombiningWithSurfaceLine_ThenCorrectNewSoilProfile2DIsCreated()
+    {
+        // Given
+        SoilProfile2D soilProfile2D = FactoryForSoilProfiles.CreateSoilProfile2DWithSixSurfacesFormingTwoLayers();
+        var defaultSoil = new Soil
+        {
+            Name = "Filling material"
+        };
+        SurfaceLine2 surfaceLine = FactoryForSurfaceLines.CreateHorizontalSurfaceLine(11, -50, 35);
+        // When
+        SoilProfile2D newSoilProfile2D = SoilProfile2DSurfaceLineHelper.CombineSurfaceLineWithSoilProfile2D(
+            surfaceLine.Geometry, soilProfile2D, defaultSoil);
+
+        // Then
+        Assert.That(newSoilProfile2D, Is.Not.Null);
+        Assert.That(newSoilProfile2D.Surfaces, Has.Count.EqualTo(6));
+        var soil1 = new Soil("Soil1");
+        var soil2 = new Soil("Soil2");
+        var soil3 = new Soil("Soil3");
+        var soil4 = new Soil("Soil4");
+        var soil5 = new Soil("Soil5");
+        SoilLayer2D expectedSurface1 = FactoryForSoilProfiles.CreateRectangularSoilLayer2D(10, 0, -50, -20, newSoilProfile2D, soil1);
+        SoilLayer2D expectedSurface2 = FactoryForSoilProfiles.CreatePentagonSoilLayer2D(new Point2D(-20, 10), new Point2D(0, 10), new Point2D(0, 0), new Point2D(-10, 0), new Point2D(-20, 0), newSoilProfile2D, soil2);
+        SoilLayer2D expectedSurface3 = FactoryForSoilProfiles.CreateRectangularSoilLayer2D(10, 0, 0, 35, newSoilProfile2D, soil3);
+        SoilLayer2D expectedSurface4 = FactoryForSoilProfiles.CreatePentagonSoilLayer2D(new Point2D(-50, 0), new Point2D(-20, 0), new Point2D(-10, 0), new Point2D(-10, -15), new Point2D(-50, -15), newSoilProfile2D, soil4);
+        SoilLayer2D expectedSurface5 = FactoryForSoilProfiles.CreatePentagonSoilLayer2D(new Point2D(-10, 0), new Point2D(0, 0), new Point2D(35, 0), new Point2D(35, -15), new Point2D(-10, -15), newSoilProfile2D, soil5);
+        SoilLayer2D expectedSurfaceFilling = FactoryForSoilProfiles.CreatePolygoneSoilLayer2D([
+            new Point2D(-50, 11), new Point2D(-28.75, 11), new Point2D(-7.5, 11), new Point2D(13.75, 11), new Point2D(35, 11), new Point2D(35, 10), new Point2D(0, 10), new Point2D(-20, 10), new Point2D(-50, 10)
+        ], defaultSoil, newSoilProfile2D);
+        CheckSoilProfileContainsSoilLayer(newSoilProfile2D, expectedSurface1);
+        CheckSoilProfileContainsSoilLayer(newSoilProfile2D, expectedSurface2);
+        CheckSoilProfileContainsSoilLayer(newSoilProfile2D, expectedSurface3);
+        CheckSoilProfileContainsSoilLayer(newSoilProfile2D, expectedSurface4);
+        CheckSoilProfileContainsSoilLayer(newSoilProfile2D, expectedSurface5);
+        CheckSoilProfileContainsSoilLayer(newSoilProfile2D, expectedSurfaceFilling);
+    }
+
     /// <summary>
     /// Test case class for GivenSoilProfile2DWhenCombiningWithSurfaceLineThenCorrectNewSoilProfile2DIsCreated()
     /// </summary>