Index: DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/GeometryHelperTests.cs
===================================================================
diff -u -r4837 -r4866
--- DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/GeometryHelperTests.cs	(.../GeometryHelperTests.cs)	(revision 4837)
+++ DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/GeometryHelperTests.cs	(.../GeometryHelperTests.cs)	(revision 4866)
@@ -43,15 +43,15 @@
         // Then
         Assert.That(soilProfile2D.Geometry.Left, Is.EqualTo(-2).Within(cTolerance));
     }
-    
+
     [Test]
     public void GivenTwoLayerGeometryWhenExtendingRigthThenLeftBoundaryIsChanged()
     {
         // Given
         SoilProfile2D soilProfile2D = FactoryForSoilProfiles.CreateSoilProfile2DWithTwoLayers();
 
         // When
-        GeometryHelper.ExtendGeometryLeft(soilProfile2D.Geometry, 12);
+        GeometryHelper.ExtendGeometryRight(soilProfile2D.Geometry, 12);
 
         // Then
         Assert.That(soilProfile2D.Geometry.Right, Is.EqualTo(12).Within(cTolerance));
Index: DamEngine/trunk/src/Deltares.DamEngine.Data/Geometry/GeometryHelper.cs
===================================================================
diff -u -r4837 -r4866
--- DamEngine/trunk/src/Deltares.DamEngine.Data/Geometry/GeometryHelper.cs	(.../GeometryHelper.cs)	(revision 4837)
+++ DamEngine/trunk/src/Deltares.DamEngine.Data/Geometry/GeometryHelper.cs	(.../GeometryHelper.cs)	(revision 4866)
@@ -64,17 +64,18 @@
         geometry.Rebox();
         geometry.Left = toX;
     }
+
     /// <summary>
     /// Extends the geometry right to the given value of x.
     /// </summary>
     /// <param name="geometry">The geometry to extend</param>
     /// <param name="toX">The x position to move the boundary to.</param>
-    private static void ExtendGeometryRight(GeometryData geometry, double toX)
+    public static void ExtendGeometryRight(GeometryData geometry, double toX)
     {
-        var rightPoints = geometry.GetRightPoints().OrderBy(x => x.Z).ToArray();
-        var rightCurves = geometry.GetRightCurves();
+        Point2D[] rightPoints = geometry.GetRightPoints().OrderBy(x => x.Z).ToArray();
+        List<GeometryCurve> rightCurves = geometry.GetRightCurves();
         Point2D prevPoint = null;
-        for (int i = 0; i < rightPoints.Length; i++)
+        for (var i = 0; i < rightPoints.Length; i++)
         {
             var newPoint = new Point2D(toX, rightPoints[i].Z);
             geometry.Points.Add(newPoint);
@@ -85,19 +86,20 @@
                 var newVerticalCurve = new GeometryCurve(newPoint, prevPoint);
                 geometry.Curves.Add(newVerticalCurve);
             }
+
             prevPoint = newPoint;
         }
-        foreach (var geometryCurve in rightCurves)
+
+        foreach (GeometryCurve geometryCurve in rightCurves)
         {
             // check if curve is vertical, only then it is on the "old" boundary and needs to be deleted
             if (Math.Abs(geometryCurve.HeadPoint.X - geometryCurve.EndPoint.X) < GeometryConstants.Accuracy)
             {
                 geometry.DeleteCurve(geometryCurve, false);
             }
         }
+
         geometry.Rebox();
         geometry.Right = toX;
     }
-
-    
 }
\ No newline at end of file
Index: DamEngine/trunk/src/Deltares.DamEngine.Data/Geometry/GeometryData.cs
===================================================================
diff -u -r4837 -r4866
--- DamEngine/trunk/src/Deltares.DamEngine.Data/Geometry/GeometryData.cs	(.../GeometryData.cs)	(revision 4837)
+++ DamEngine/trunk/src/Deltares.DamEngine.Data/Geometry/GeometryData.cs	(.../GeometryData.cs)	(revision 4866)
@@ -695,15 +695,13 @@
         var leftCurves = new List<GeometryCurve>();
         foreach (GeometryCurve geometryCurve in Curves)
         {
-            if (geometryCurve.HeadPoint.X <= Left && geometryCurve.EndPoint.X >= Left)
+            if ((geometryCurve.HeadPoint.X <= Left && geometryCurve.EndPoint.X >= Left) ||
+                (geometryCurve.HeadPoint.X >= Left && geometryCurve.EndPoint.X <= Left))
             {
                 leftCurves.Add(geometryCurve);
             }
-            else if (geometryCurve.HeadPoint.X >= Left && geometryCurve.EndPoint.X <= Left)
-            {
-                leftCurves.Add(geometryCurve);
-            }
         }
+
         return leftCurves;
     }
 
@@ -714,20 +712,18 @@
     public List<GeometryCurve> GetRightCurves()
     {
         var rightCurves = new List<GeometryCurve>();
-        foreach (var curve in Curves)
+        foreach (GeometryCurve curve in Curves)
         {
-            if (curve.HeadPoint.X <= Right && curve.EndPoint.X >= Right)
+            if ((curve.HeadPoint.X <= Right && curve.EndPoint.X >= Right) ||
+                (curve.HeadPoint.X >= Right && curve.EndPoint.X <= Right))
             {
                 rightCurves.Add(curve);
             }
-            else if (curve.HeadPoint.X >= Right && curve.EndPoint.X <= Right)
-            {
-                rightCurves.Add(curve);
-            }
         }
+
         return rightCurves;
     }
-    
+
     /// <summary>
     /// Gets the geometry bounds.
     /// </summary>