Index: DamEngine/trunk/src/Deltares.DamEngine.Interface.Tests/FillDamFromXmlInputTests.cs
===================================================================
diff -u -r1405 -r1408
--- DamEngine/trunk/src/Deltares.DamEngine.Interface.Tests/FillDamFromXmlInputTests.cs	(.../FillDamFromXmlInputTests.cs)	(revision 1405)
+++ DamEngine/trunk/src/Deltares.DamEngine.Interface.Tests/FillDamFromXmlInputTests.cs	(.../FillDamFromXmlInputTests.cs)	(revision 1408)
@@ -240,6 +240,8 @@
             AddPointToSurfaceLine(surfaceLine, 9.0, 5.0, CharacteristicPointType.DikeTopAtRiver);
             AddPointToSurfaceLine(surfaceLine, 10.0, 5.2, CharacteristicPointType.None);
             AddPointToSurfaceLine(surfaceLine, 13.0, 5.4, CharacteristicPointType.DikeTopAtPolder);
+            AddPointToSurfaceLine(surfaceLine, 13.0, 5.4, CharacteristicPointType.TrafficLoadOutside);
+            AddPointToSurfaceLine(surfaceLine, 14.0, 4.52, CharacteristicPointType.TrafficLoadInside);
             AddPointToSurfaceLine(surfaceLine, 18.0, 1.0, CharacteristicPointType.DikeToeAtPolder);
             AddPointToSurfaceLine(surfaceLine, 24.0, 1.0, CharacteristicPointType.SurfaceLevelInside);
         }
Index: DamEngine/trunk/src/Deltares.DamEngine.Data/Geotechnics/CharacteristicPointSet.cs
===================================================================
diff -u -r877 -r1408
--- DamEngine/trunk/src/Deltares.DamEngine.Data/Geotechnics/CharacteristicPointSet.cs	(.../CharacteristicPointSet.cs)	(revision 877)
+++ DamEngine/trunk/src/Deltares.DamEngine.Data/Geotechnics/CharacteristicPointSet.cs	(.../CharacteristicPointSet.cs)	(revision 1408)
@@ -410,8 +410,24 @@
                         }
                     }
                 }
-                PerformListInsertWithEvents(Geometry.Points, item.GeometryPoint, geometryIndex);
-            }
+                // Check if point at same position already exists and set that point to the existing point
+                // Do this to avoid points in Surfaceline.Geometry with the same location
+                bool IsPointExist = false;
+                for (int i = 0; i < Geometry.Points.Count; i++)
+                {
+                    if (Geometry.Points[i].LocationEquals(item.GeometryPoint))
+                    {
+                        item.GeometryPoint = Geometry.Points[i];
+                        IsPointExist = true;
+                        break;
+                    }
+                }
+                if (!IsPointExist)
+                {
+                    // Only add new point if no point on same location was found
+                    PerformListInsertWithEvents(Geometry.Points, item.GeometryPoint, geometryIndex);
+                }
+           }
 
             UpdateCharacteristicPointHeight(item);
             UpdateTypeCache(item);            
Index: DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/SurfaceLine2Tests.cs
===================================================================
diff -u
--- DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/SurfaceLine2Tests.cs	(revision 0)
+++ DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Geotechnics/SurfaceLine2Tests.cs	(revision 1408)
@@ -0,0 +1,63 @@
+// Copyright (C) Stichting Deltares 2018. All rights reserved.
+//
+// This file is part of the Dam Engine.
+//
+// The Dam Engine is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+// All names, logos, and references to "Deltares" are registered trademarks of
+// Stichting Deltares and remain full property of Stichting Deltares at all times.
+// All rights reserved.
+
+using Deltares.DamEngine.Data.Geometry;
+using Deltares.DamEngine.Data.Geotechnics;
+using NUnit.Framework;
+
+namespace Deltares.DamEngine.Data.Tests.Geotechnics
+{
+    [TestFixture]
+    public class SurfaceLine2Tests
+    {
+        [Test]
+        public void TestAddingCharacteristicPointsOnSameLocationDoesNotAddDoublePointsInGeometry()
+        {
+            SurfaceLine2 surfaceLine = new SurfaceLine2();
+            surfaceLine.CharacteristicPoints.Geometry = surfaceLine.Geometry;
+            AddPointToSurfaceLine(surfaceLine, 0.0, 0.0, CharacteristicPointType.SurfaceLevelOutside);
+            AddPointToSurfaceLine(surfaceLine, 2.0, 0.5, CharacteristicPointType.None);
+            AddPointToSurfaceLine(surfaceLine, 4.0, 0.0, CharacteristicPointType.DikeToeAtRiver);
+            AddPointToSurfaceLine(surfaceLine, 9.0, 5.0, CharacteristicPointType.DikeTopAtRiver);
+            AddPointToSurfaceLine(surfaceLine, 10.0, 5.2, CharacteristicPointType.None);
+            AddPointToSurfaceLine(surfaceLine, 13.0, 5.4, CharacteristicPointType.DikeTopAtPolder);
+            AddPointToSurfaceLine(surfaceLine, 13.0, 5.4, CharacteristicPointType.TrafficLoadOutside);
+            AddPointToSurfaceLine(surfaceLine, 14.0, 4.52, CharacteristicPointType.TrafficLoadInside);
+            AddPointToSurfaceLine(surfaceLine, 18.0, 1.0, CharacteristicPointType.DikeToeAtPolder);
+            AddPointToSurfaceLine(surfaceLine, 24.0, 1.0, CharacteristicPointType.SurfaceLevelInside);
+            surfaceLine.Geometry.SyncCalcPoints();
+            Assert.AreEqual(10, surfaceLine.CharacteristicPoints.Count);
+            // Because TrafficLoadOutside and DikeTopAtPolder are on the same location, 1 point less should be in the geometry
+            Assert.AreEqual(9, surfaceLine.Geometry.Points.Count);
+        }
+
+        private void AddPointToSurfaceLine(SurfaceLine2 surfaceLine, double xCoordinate, double zCoordinate, CharacteristicPointType characteristicPointType)
+        {
+            var geometryPoint = new GeometryPoint()
+            {
+                X = xCoordinate,
+                Y = 0.0,
+                Z = zCoordinate,
+            };
+            surfaceLine.AddCharacteristicPoint(geometryPoint, characteristicPointType);
+        }
+    }
+}
Index: DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Deltares.DamEngine.Data.Tests.csproj
===================================================================
diff -u -r877 -r1408
--- DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Deltares.DamEngine.Data.Tests.csproj	(.../Deltares.DamEngine.Data.Tests.csproj)	(revision 877)
+++ DamEngine/trunk/src/Deltares.DamEngine.Data.Tests/Deltares.DamEngine.Data.Tests.csproj	(.../Deltares.DamEngine.Data.Tests.csproj)	(revision 1408)
@@ -47,6 +47,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Geotechnics\SoilProfile1DAquiferLayerCombinerTests.cs" />
+    <Compile Include="Geotechnics\SurfaceLine2Tests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
   </ItemGroup>
   <ItemGroup>