Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Factories/MacroStabilityInwardsChartDataFactory.cs
===================================================================
diff -u -ra371ae048cf582e8a9cad8436a21c2b9b18dc793 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Factories/MacroStabilityInwardsChartDataFactory.cs	(.../MacroStabilityInwardsChartDataFactory.cs)	(revision a371ae048cf582e8a9cad8436a21c2b9b18dc793)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Factories/MacroStabilityInwardsChartDataFactory.cs	(.../MacroStabilityInwardsChartDataFactory.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -102,7 +102,8 @@
             {
                 Color = Color.Blue,
                 DashStyle = ChartLineDashStyle.Solid,
-                Width = 2
+                Width = 2,
+                IsEditable = true
             })
             {
                 IsVisible = isVisible
@@ -284,6 +285,22 @@
         }
 
         /// <summary>
+        /// Creates <see cref="ChartMultipleLineData"/> with default styling for the tangent lines.
+        /// </summary>
+        /// <returns>The created <see cref="ChartMultipleLineData"/>.</returns>
+        public static ChartMultipleLineData CreateTangentLinesChartData()
+        {
+            return new ChartMultipleLineData(Resources.TangentLines_DisplayName,
+                                             new ChartLineStyle
+                                             {
+                                                 Color = Color.Green,
+                                                 DashStyle = ChartLineDashStyle.Dash,
+                                                 IsEditable = true,
+                                                 Width = 1
+                                             });
+        }
+
+        /// <summary>
         /// Updates the name of <paramref name="chartData"/> based on <paramref name="surfaceLine"/>.
         /// </summary>
         /// <param name="chartData">The <see cref="ChartLineData"/> to update the name for.</param>
Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Factories/MacroStabilityInwardsChartDataPointsFactory.cs
===================================================================
diff -u -rcac3045aae8af73cbc3602a1c38b071385aa3581 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Factories/MacroStabilityInwardsChartDataPointsFactory.cs	(.../MacroStabilityInwardsChartDataPointsFactory.cs)	(revision cac3045aae8af73cbc3602a1c38b071385aa3581)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Factories/MacroStabilityInwardsChartDataPointsFactory.cs	(.../MacroStabilityInwardsChartDataPointsFactory.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -399,8 +399,31 @@
         }
 
         /// <summary>
-        /// Create areas of the slices based on the provided <paramref name="slices"/>.
+        /// Create the tangent lines based on the provided <paramref name="tangentLines"/>
+        /// and <paramref name="surfaceLine"/>.
         /// </summary>
+        /// <param name="tangentLines">The tangent line Y-coordinates.</param>
+        /// <param name="surfaceLine">The surface line that determines the boundaries of the tangent line.</param>
+        /// <returns>A collection of arrays of points in 2D space or an empty collection when <paramref name="surfaceLine"/>
+        /// or <paramref name="tangentLines"/> is <c>null</c>.</returns>
+        public static IEnumerable<Point2D[]> CreateTangentLines(IEnumerable<double> tangentLines,
+                                                                MacroStabilityInwardsSurfaceLine surfaceLine)
+        {
+            if (surfaceLine == null || tangentLines == null)
+            {
+                return Enumerable.Empty<Point2D[]>();
+            }
+
+            return tangentLines.Select(tangentLine => new[]
+            {
+                new Point2D(surfaceLine.LocalGeometry.First().X, tangentLine),
+                new Point2D(surfaceLine.LocalGeometry.Last().X, tangentLine)
+            }).ToArray();
+        }
+
+        /// <summary>
+        /// Create lines of the slices based on the provided <paramref name="slices"/>.
+        /// </summary>
         /// <param name="slices">The slices to create the areas for.</param>
         /// <returns>A collection of arrays of points in 2D space or an empty collection when <paramref name="slices"/>
         /// is <c>null</c>.</returns>
Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Properties/Resources.Designer.cs
===================================================================
diff -u -r1d682d2d79d3dc08fc5a8c0ebac889d996dfb492 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 1d682d2d79d3dc08fc5a8c0ebac889d996dfb492)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -1581,6 +1581,15 @@
         }
         
         /// <summary>
+        ///   Looks up a localized string similar to Tangentlijnen.
+        /// </summary>
+        public static string TangentLines_DisplayName {
+            get {
+                return ResourceManager.GetString("TangentLines_DisplayName", resourceCulture);
+            }
+        }
+        
+        /// <summary>
         ///   Looks up a localized string similar to Verticale coördinaat van de onderste raaklijn..
         /// </summary>
         public static string TangentLineZBottom_Description {
Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Properties/Resources.resx
===================================================================
diff -u -r1d682d2d79d3dc08fc5a8c0ebac889d996dfb492 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Properties/Resources.resx	(.../Resources.resx)	(revision 1d682d2d79d3dc08fc5a8c0ebac889d996dfb492)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Properties/Resources.resx	(.../Resources.resx)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -469,6 +469,9 @@
   <data name="PassiveCircleRadius_DisplayName" xml:space="preserve">
     <value>Radius passieve cirkel</value>
   </data>
+  <data name="TangentLines_DisplayName" xml:space="preserve">
+    <value>Tangentlijnen</value>
+  </data>
   <data name="TangentLineDeterminationType_Description" xml:space="preserve">
     <value>Bepaling raaklijnen op basis van grondlaagscheidingen of handmatig?</value>
   </data>
Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Views/MacroStabilityInwardsOutputChartControl.cs
===================================================================
diff -u -ra371ae048cf582e8a9cad8436a21c2b9b18dc793 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Views/MacroStabilityInwardsOutputChartControl.cs	(.../MacroStabilityInwardsOutputChartControl.cs)	(revision a371ae048cf582e8a9cad8436a21c2b9b18dc793)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Forms/Views/MacroStabilityInwardsOutputChartControl.cs	(.../MacroStabilityInwardsOutputChartControl.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -63,6 +63,7 @@
         private readonly ChartLineData slipPlaneChartData;
         private readonly ChartLineData leftCircleRadiusChartData;
         private readonly ChartLineData rightCircleRadiusChartData;
+        private readonly ChartMultipleLineData tangentLinesChartData;
 
         private readonly List<ChartMultipleAreaData> soilLayerChartDataLookup;
 
@@ -101,6 +102,7 @@
             surfaceLevelOutsideChartData = MacroStabilityInwardsChartDataFactory.CreateSurfaceLevelOutsideChartData();
             waternetZonesExtremeChartData = MacroStabilityInwardsChartDataFactory.CreateWaternetZonesExtremeChartDataCollection();
             waternetZonesDailyChartData = MacroStabilityInwardsChartDataFactory.CreateWaternetZonesDailyChartDataCollection();
+            tangentLinesChartData = MacroStabilityInwardsChartDataFactory.CreateTangentLinesChartData();
             leftGridChartData = MacroStabilityInwardsChartDataFactory.CreateLeftGridChartData();
             rightGridChartData = MacroStabilityInwardsChartDataFactory.CreateRightGridChartData();
             slipPlaneChartData = MacroStabilityInwardsChartDataFactory.CreateSlipPlaneChartData();
@@ -124,6 +126,7 @@
             chartDataCollection.Add(surfaceLevelOutsideChartData);
             chartDataCollection.Add(waternetZonesExtremeChartData);
             chartDataCollection.Add(waternetZonesDailyChartData);
+            chartDataCollection.Add(tangentLinesChartData);
             chartDataCollection.Add(leftGridChartData);
             chartDataCollection.Add(rightGridChartData);
             chartDataCollection.Add(slicesChartData);
@@ -189,6 +192,8 @@
             leftCircleRadiusChartData.Points = MacroStabilityInwardsChartDataPointsFactory.CreateLeftCircleRadiusPoints(output?.SlidingCurve);
             rightCircleRadiusChartData.Points = MacroStabilityInwardsChartDataPointsFactory.CreateRightCircleRadiusPoints(output?.SlidingCurve);
             slicesChartData.Areas = MacroStabilityInwardsChartDataPointsFactory.CreateSliceAreas(output?.SlidingCurve.Slices);
+            tangentLinesChartData.Lines = MacroStabilityInwardsChartDataPointsFactory.CreateTangentLines(output?.SlipPlane.TangentLines,
+                                                                                                         data.InputParameters.SurfaceLine);
         }
 
         private void UpdateInputChartData()
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.TestUtil.Test/MacroStabilityInwardsOutputTestFactoryTest.cs
===================================================================
diff -u -ra1f0bed43a1bdeeda53ac505a77c065ca6fd7c12 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.TestUtil.Test/MacroStabilityInwardsOutputTestFactoryTest.cs	(.../MacroStabilityInwardsOutputTestFactoryTest.cs)	(revision a1f0bed43a1bdeeda53ac505a77c065ca6fd7c12)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.TestUtil.Test/MacroStabilityInwardsOutputTestFactoryTest.cs	(.../MacroStabilityInwardsOutputTestFactoryTest.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -84,6 +84,12 @@
             Assert.IsNotNull(output.SlidingCurve);
             Assert.AreEqual(3, output.SlidingCurve.Slices.Count());
             Assert.IsNotNull(output.SlipPlane);
+            CollectionAssert.AreEqual(new[]
+            {
+                -3.5,
+                0.0,
+                2.0
+            }, output.SlipPlane.TangentLines);
         }
 
         [Test]
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.TestUtil/MacroStabilityInwardsOutputTestFactory.cs
===================================================================
diff -u -rb513e76d805898795483251f7d070489dfd20b9b -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.TestUtil/MacroStabilityInwardsOutputTestFactory.cs	(.../MacroStabilityInwardsOutputTestFactory.cs)	(revision b513e76d805898795483251f7d070489dfd20b9b)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.TestUtil/MacroStabilityInwardsOutputTestFactory.cs	(.../MacroStabilityInwardsOutputTestFactory.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -74,7 +74,12 @@
                                                                                          }, 0, 0),
                                                    new MacroStabilityInwardsSlipPlaneUpliftVan(MacroStabilityInwardsGridTestFactory.Create(),
                                                                                                MacroStabilityInwardsGridTestFactory.Create(),
-                                                                                               new double[0]),
+                                                                                               new[]
+                                                                                               {
+                                                                                                   -3.5,
+                                                                                                   0.0,
+                                                                                                   2.0
+                                                                                               }),
                                                    properties);
         }
 
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/Factories/MacroStabilityInwardsChartDataFactoryTest.cs
===================================================================
diff -u -ra371ae048cf582e8a9cad8436a21c2b9b18dc793 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/Factories/MacroStabilityInwardsChartDataFactoryTest.cs	(.../MacroStabilityInwardsChartDataFactoryTest.cs)	(revision a371ae048cf582e8a9cad8436a21c2b9b18dc793)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/Factories/MacroStabilityInwardsChartDataFactoryTest.cs	(.../MacroStabilityInwardsChartDataFactoryTest.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -308,6 +308,18 @@
         }
 
         [Test]
+        public void CreateTangentLinesChartData_ReturnsChartMultipleLineData()
+        {
+            // Call
+            ChartMultipleLineData data = MacroStabilityInwardsChartDataFactory.CreateTangentLinesChartData();
+
+            // Assert
+            CollectionAssert.IsEmpty(data.Lines);
+            Assert.AreEqual("Tangentlijnen", data.Name);
+            AssertEqualStyle(data.Style, Color.Green, 1, ChartLineDashStyle.Dash);
+        }
+
+        [Test]
         public void UpdateSurfaceLineChartDataName_SurfaceLineNull_NameSetToDefaultSurfaceLineName()
         {
             // Setup
@@ -388,6 +400,7 @@
             Assert.AreEqual(color, lineStyle.Color);
             Assert.AreEqual(width, lineStyle.Width);
             Assert.AreEqual(dashStyle, lineStyle.DashStyle);
+            Assert.IsTrue(lineStyle.IsEditable);
         }
     }
 }
\ No newline at end of file
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/Factories/MacroStabilityInwardsChartDataPointsFactoryTest.cs
===================================================================
diff -u -r7946e60ec6d419d8b4a7cfbf61e93f2738139843 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/Factories/MacroStabilityInwardsChartDataPointsFactoryTest.cs	(.../MacroStabilityInwardsChartDataPointsFactoryTest.cs)	(revision 7946e60ec6d419d8b4a7cfbf61e93f2738139843)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/Factories/MacroStabilityInwardsChartDataPointsFactoryTest.cs	(.../MacroStabilityInwardsChartDataPointsFactoryTest.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -1452,6 +1452,60 @@
             }, areas);
         }
 
+        [Test]
+        public void CreateTangentLines_TangentLinesNull_ReturnsEmptyCollection()
+        {
+            // Call
+            IEnumerable<Point2D[]> areas = MacroStabilityInwardsChartDataPointsFactory.CreateTangentLines(null, new MacroStabilityInwardsSurfaceLine("line"));
+
+            // Assert
+            CollectionAssert.IsEmpty(areas);
+        }
+
+        [Test]
+        public void CreateTangentLines_SurfaceLineNull_ReturnsEmptyCollection()
+        {
+            // Call
+            IEnumerable<Point2D[]> areas = MacroStabilityInwardsChartDataPointsFactory.CreateTangentLines(Enumerable.Empty<double>(), null);
+
+            // Assert
+            CollectionAssert.IsEmpty(areas);
+        }
+
+        [Test]
+        public void CreateTangentLines_WithSlices_ReturnsLines()
+        {
+            // Setup
+            var surfaceLine = new MacroStabilityInwardsSurfaceLine("line");
+            surfaceLine.SetGeometry(new[]
+            {
+                new Point3D(-5, 2, 2),
+                new Point3D(10, 2, 2)
+            });
+
+            // Call
+            IEnumerable<Point2D[]> lines = MacroStabilityInwardsChartDataPointsFactory.CreateTangentLines(new[]
+            {
+                2.5,
+                5.8
+            }, surfaceLine);
+
+            // Assert
+            CollectionAssert.AreEqual(new[]
+            {
+                new[]
+                {
+                    new Point2D(0.0, 2.5),
+                    new Point2D(15.0, 2.5)
+                },
+                new[]
+                {
+                    new Point2D(0, 5.8),
+                    new Point2D(15.0, 5.8)
+                }
+            }, lines);
+        }
+
         private static MacroStabilityInwardsWaternetLine CreateWaternetLine(IEnumerable<Point2D> waternetLineGeometry,
                                                                             IEnumerable<Point2D> phreaticLineGeometry)
         {
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.TestUtil/MacroStabilityInwardsOutputViewChartDataAssert.cs
===================================================================
diff -u -ra371ae048cf582e8a9cad8436a21c2b9b18dc793 -r2351e33d2db5e822abd37b63a88930d9239528b7
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.TestUtil/MacroStabilityInwardsOutputViewChartDataAssert.cs	(.../MacroStabilityInwardsOutputViewChartDataAssert.cs)	(revision a371ae048cf582e8a9cad8436a21c2b9b18dc793)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.TestUtil/MacroStabilityInwardsOutputViewChartDataAssert.cs	(.../MacroStabilityInwardsOutputViewChartDataAssert.cs)	(revision 2351e33d2db5e822abd37b63a88930d9239528b7)
@@ -51,13 +51,14 @@
         private const int surfaceLevelOutsideIndex = 13;
         private const int waternetZonesExtremeIndex = 14;
         private const int waternetZonesDailyIndex = 15;
-        private const int leftGridIndex = 16;
-        private const int rightGridIndex = 17;
-        private const int slicesIndex = 18;
-        private const int slipPlaneIndex = 19;
-        private const int activeCircleRadiusIndex = 20;
-        private const int passiveCircleRadiusIndex = 21;
-        private const int nrOfChartData = 22;
+        private const int tangentLinesIndex = 16;
+        private const int leftGridIndex = 17;
+        private const int rightGridIndex = 18;
+        private const int slicesIndex = 19;
+        private const int slipPlaneIndex = 20;
+        private const int activeCircleRadiusIndex = 21;
+        private const int passiveCircleRadiusIndex = 22;
+        private const int nrOfChartData = 23;
 
         /// <summary>
         /// Asserts whether <paramref name="actual"/> corresponds to the input of <paramref name="calculationScenario"/>.
@@ -97,6 +98,9 @@
             MacroStabilityInwardsViewChartDataAssert.AssertGridChartData(calculationScenario.Output.SlipPlane.RightGrid,
                                                                          (ChartPointData) actual.Collection.ElementAt(rightGridIndex));
 
+            AssertTangentLinesChartData(calculationScenario.Output.SlipPlane.TangentLines, calculationScenario.InputParameters.SurfaceLine,
+                                        (ChartMultipleLineData) actual.Collection.ElementAt(tangentLinesIndex));
+
             AssertSlicesChartData(calculationScenario.Output.SlidingCurve.Slices,
                                   (ChartMultipleAreaData) actual.Collection.ElementAt(slicesIndex));
 
@@ -135,20 +139,23 @@
             ChartData[] chartDataArray = chartDataCollection.Collection.ToArray();
 
             Assert.AreEqual(nrOfChartData, chartDataArray.Length);
+            var tangentLinesData = (ChartMultipleLineData) chartDataArray[tangentLinesIndex];
             var leftGridData = (ChartPointData) chartDataArray[leftGridIndex];
             var rightGridData = (ChartPointData) chartDataArray[rightGridIndex];
             var slicesData = (ChartMultipleAreaData) chartDataArray[slicesIndex];
             var slipPlaneData = (ChartLineData) chartDataArray[slipPlaneIndex];
             var activeCircleRadiusData = (ChartLineData) chartDataArray[activeCircleRadiusIndex];
             var passiveCircleRadiusData = (ChartLineData) chartDataArray[passiveCircleRadiusIndex];
 
+            CollectionAssert.IsEmpty(tangentLinesData.Lines);
             CollectionAssert.IsEmpty(leftGridData.Points);
             CollectionAssert.IsEmpty(rightGridData.Points);
             CollectionAssert.IsEmpty(slicesData.Areas);
             CollectionAssert.IsEmpty(slipPlaneData.Points);
             CollectionAssert.IsEmpty(activeCircleRadiusData.Points);
             CollectionAssert.IsEmpty(passiveCircleRadiusData.Points);
 
+            Assert.AreEqual("Tangentlijnen", tangentLinesData.Name);
             Assert.AreEqual("Linker grid", leftGridData.Name);
             Assert.AreEqual("Rechter grid", rightGridData.Name);
             Assert.AreEqual("Lamellen", slicesData.Name);
@@ -214,6 +221,33 @@
         }
 
         /// <summary>
+        /// Asserts whether <paramref name="actual"/> corresponds to <paramref name="tangentLines"/>
+        /// and <paramref name="surfaceLine"/>.
+        /// </summary>
+        /// <param name="tangentLines">The original tangent line Y-coordinates.</param>
+        /// <param name="surfaceLine">The original surface line.</param>
+        /// <param name="actual">The actual <see cref="ChartMultipleLineData"/>.</param>
+        /// <exception cref="AssertionException">Thrown when <paramref name="actual"/>
+        /// does not correspond to <paramref name="tangentLines"/> and <paramref name="surfaceLine"/>.
+        /// </exception>
+        private static void AssertTangentLinesChartData(IEnumerable<double> tangentLines,
+                                                        MacroStabilityInwardsSurfaceLine surfaceLine,
+                                                        ChartMultipleLineData actual)
+        {
+            CollectionAssert.IsNotEmpty(actual.Lines);
+            double[] tangentLinesArray = tangentLines.ToArray();
+            for (var i = 0; i < tangentLinesArray.Length; i++)
+            {
+                var expectedPoints = new[]
+                {
+                    new Point2D(surfaceLine.LocalGeometry.First().X, tangentLinesArray[i]),
+                    new Point2D(surfaceLine.LocalGeometry.Last().X, tangentLinesArray[i])
+                };
+                CollectionAssert.AreEqual(expectedPoints, actual.Lines.ElementAt(i));
+            }
+        }
+
+        /// <summary>
         /// Asserts whether <paramref name="actual"/> corresponds to <paramref name="slices"/>.
         /// </summary>
         /// <param name="slices">The original slices.</param>