Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.KernelWrapper/Calculators/UpliftVan/Input/UpliftVanDrainageConstruction.cs
===================================================================
diff -u -r82014e97419537804be86264d0ed501637ccd10f -rf41767008e9489269fcd67a0a60608d8ddb8ac13
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.KernelWrapper/Calculators/UpliftVan/Input/UpliftVanDrainageConstruction.cs	(.../UpliftVanDrainageConstruction.cs)	(revision 82014e97419537804be86264d0ed501637ccd10f)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.KernelWrapper/Calculators/UpliftVan/Input/UpliftVanDrainageConstruction.cs	(.../UpliftVanDrainageConstruction.cs)	(revision f41767008e9489269fcd67a0a60608d8ddb8ac13)
@@ -39,7 +39,7 @@
         }
 
         /// <summary>
-        /// Creates a new instance of <see cref="UpliftVanDrainageConstruction"/>
+        /// Creates a new instance of <see cref="UpliftVanDrainageConstruction"/>.
         /// </summary>
         /// <param name="xCoordinate">The x coordinate of the drainage construction.</param>
         /// <param name="zCoordinate">The z coordinate of the drainage construction.</param>
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.KernelWrapper.Test/Creators/Input/StabilityLocationCreatorTest.cs
===================================================================
diff -u -rc50841e1e3dbc1e2759861f906058645e19b2a01 -rf41767008e9489269fcd67a0a60608d8ddb8ac13
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.KernelWrapper.Test/Creators/Input/StabilityLocationCreatorTest.cs	(.../StabilityLocationCreatorTest.cs)	(revision c50841e1e3dbc1e2759861f906058645e19b2a01)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.KernelWrapper.Test/Creators/Input/StabilityLocationCreatorTest.cs	(.../StabilityLocationCreatorTest.cs)	(revision f41767008e9489269fcd67a0a60608d8ddb8ac13)
@@ -198,7 +198,9 @@
         }
 
         [Test]
-        public void Create_WithInput_ReturnStabilityLocation()
+        [Combinatorial]
+        public void Create_WithInput_ReturnStabilityLocation([Values(true, false)] bool drainageConstructionPresent,
+            [Values(true, false)] bool useDefaultOffsets)
         {
             // Setup
             var random = new Random(21);
@@ -222,8 +224,14 @@
             double piezometricHeadPhreaticLine2Inwards = random.Next();
             double penetrationLength = random.Next();
 
-            var drainageConstruction = new UpliftVanDrainageConstruction(xCoordinateDrainageConstruction, zCoordinateDrainageConstruction);
-            var phreaticLineOffsets = new UpliftVanPhreaticLineOffsets(phreaticLineOffsetBelowDikeTopAtRiver, phreaticLineOffsetBelowDikeTopAtPolder,
+            UpliftVanDrainageConstruction drainageConstruction = drainageConstructionPresent
+                                                                     ? new UpliftVanDrainageConstruction(
+                                                                         xCoordinateDrainageConstruction, zCoordinateDrainageConstruction)
+                                                                     : new UpliftVanDrainageConstruction();
+            UpliftVanPhreaticLineOffsets phreaticLineOffsets = useDefaultOffsets
+                                                                   ? new UpliftVanPhreaticLineOffsets()
+                                                                   : new UpliftVanPhreaticLineOffsets(
+                                                                       phreaticLineOffsetBelowDikeTopAtRiver, phreaticLineOffsetBelowDikeTopAtPolder,
                                                                        phreaticLineOffsetBelowDikeToeAtPolder, phreaticLineOffsetBelowShoulderBaseInside);
 
             var input = new UpliftVanCalculatorInput(
@@ -232,7 +240,7 @@
                     SurfaceLine = new MacroStabilityInwardsSurfaceLine("test"),
                     SoilProfile = new TestUpliftVanSoilProfile(),
                     SlipPlane = new UpliftVanSlipPlane(),
-                    DikeSoilScenario = MacroStabilityInwardsDikeSoilScenario.ClayDikeOnClay,
+                    DikeSoilScenario = MacroStabilityInwardsDikeSoilScenario.SandDikeOnClay,
                     AssessmentLevel = assessmentLevel,
                     WaterLevelRiverAverage = waterLevelRiverAverage,
                     WaterLevelPolder = waterLevelPolder,
@@ -254,23 +262,24 @@
             StabilityLocation location = StabilityLocationCreator.Create(input);
 
             // Assert
-            Assert.AreEqual(DikeSoilScenario.ClayDikeOnClay, location.DikeSoilScenario);
+            Assert.AreEqual(DikeSoilScenario.SandDikeOnClay, location.DikeSoilScenario);
             Assert.AreEqual(WaternetCreationMode.CreateWaternet, location.WaternetCreationMode);
             Assert.AreEqual(PlLineCreationMethod.RingtoetsWti2017, location.PlLineCreationMethod);
             Assert.AreEqual(assessmentLevel, location.WaterLevelRiver);
             Assert.AreEqual(assessmentLevel, location.HeadInPlLine3);
             Assert.AreEqual(assessmentLevel, location.HeadInPlLine4);
             Assert.AreEqual(waterLevelRiverAverage, location.WaterLevelRiverAverage);
             Assert.AreEqual(waterLevelPolder, location.WaterLevelPolder);
-            Assert.AreEqual(xCoordinateDrainageConstruction, location.XCoordMiddleDrainageConstruction);
-            Assert.AreEqual(zCoordinateDrainageConstruction, location.ZCoordMiddleDrainageConstruction);
+            Assert.AreEqual(drainageConstruction.IsPresent, location.DrainageConstructionPresent);
+            Assert.AreEqual(drainageConstruction.XCoordinate, location.XCoordMiddleDrainageConstruction);
+            Assert.AreEqual(drainageConstruction.ZCoordinate, location.ZCoordMiddleDrainageConstruction);
             Assert.AreEqual(minimumLevelPhreaticLineAtDikeTopRiver, location.MinimumLevelPhreaticLineAtDikeTopRiver);
             Assert.AreEqual(minimumLevelPhreaticLineAtDikeTopPolder, location.MinimumLevelPhreaticLineAtDikeTopPolder);
-            Assert.IsFalse(location.UseDefaultOffsets);
-            Assert.AreEqual(phreaticLineOffsetBelowDikeTopAtRiver, location.PlLineOffsetBelowPointBRingtoetsWti2017);
-            Assert.AreEqual(phreaticLineOffsetBelowDikeTopAtPolder, location.PlLineOffsetBelowDikeTopAtPolder);
-            Assert.AreEqual(phreaticLineOffsetBelowShoulderBaseInside, location.PlLineOffsetBelowShoulderBaseInside);
-            Assert.AreEqual(phreaticLineOffsetBelowDikeToeAtPolder, location.PlLineOffsetBelowDikeToeAtPolder);
+            Assert.AreEqual(phreaticLineOffsets.UseDefaults, location.UseDefaultOffsets);
+            Assert.AreEqual(phreaticLineOffsets.BelowDikeTopAtRiver, location.PlLineOffsetBelowPointBRingtoetsWti2017);
+            Assert.AreEqual(phreaticLineOffsets.BelowDikeTopAtPolder, location.PlLineOffsetBelowDikeTopAtPolder);
+            Assert.AreEqual(phreaticLineOffsets.BelowShoulderBaseInside, location.PlLineOffsetBelowShoulderBaseInside);
+            Assert.AreEqual(phreaticLineOffsets.BelowDikeToeAtPolder, location.PlLineOffsetBelowDikeToeAtPolder);
             Assert.AreEqual(adjustPhreaticLine3And4ForUplift, location.AdjustPl3And4ForUplift);
             Assert.AreEqual(leakageLengthOutwardsPhreaticLine3, location.LeakageLengthOutwardsPl3);
             Assert.AreEqual(leakageLengthInwardsPhreaticLine3, location.LeakageLengthInwardsPl3);
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Service.Test/MacroStabilityInwardsCalculationServiceTest.cs
===================================================================
diff -u -r0972b795d89686b6ae07a1b256fc2db51f524c9f -rf41767008e9489269fcd67a0a60608d8ddb8ac13
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Service.Test/MacroStabilityInwardsCalculationServiceTest.cs	(.../MacroStabilityInwardsCalculationServiceTest.cs)	(revision 0972b795d89686b6ae07a1b256fc2db51f524c9f)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Service.Test/MacroStabilityInwardsCalculationServiceTest.cs	(.../MacroStabilityInwardsCalculationServiceTest.cs)	(revision f41767008e9489269fcd67a0a60608d8ddb8ac13)
@@ -477,7 +477,7 @@
                 // Assert
                 UpliftVanCalculatorInput actualInput = ((TestMacroStabilityInwardsCalculatorFactory) MacroStabilityInwardsCalculatorFactory.Instance)
                     .LastCreatedUpliftVanCalculator.Input;
-                Assert.IsFalse(actualInput.DrainageConstruction.IsPresent);
+                Assert.IsTrue(actualInput.PhreaticLineOffsets.UseDefaults);
                 Assert.IsNaN(actualInput.PhreaticLineOffsets.BelowDikeToeAtPolder);
                 Assert.IsNaN(actualInput.PhreaticLineOffsets.BelowDikeTopAtPolder);
                 Assert.IsNaN(actualInput.PhreaticLineOffsets.BelowDikeTopAtRiver);
@@ -486,6 +486,44 @@
         }
 
         [Test]
+        public void Calculate_GridDeterminationTypeAutomatic_SetsInputOnCalculator()
+        {
+            // Setup
+            var random = new Random(11);
+            MacroStabilityInwardsInput inputParameters = testCalculation.InputParameters;
+            inputParameters.GridDeterminationType = MacroStabilityInwardsGridDeterminationType.Automatic;
+            inputParameters.TangentLineZTop = random.NextRoundedDouble();
+            inputParameters.TangentLineZBottom = random.NextRoundedDouble();
+            inputParameters.LeftGrid.XLeft = random.NextRoundedDouble();
+            inputParameters.LeftGrid.XRight = random.NextRoundedDouble();
+            inputParameters.LeftGrid.ZTop = random.NextRoundedDouble();
+            inputParameters.LeftGrid.ZBottom = random.NextRoundedDouble();
+            inputParameters.LeftGrid.NumberOfHorizontalPoints = random.Next();
+            inputParameters.LeftGrid.NumberOfVerticalPoints = random.Next();
+            inputParameters.RightGrid.XLeft = random.NextRoundedDouble();
+            inputParameters.RightGrid.XRight = random.NextRoundedDouble();
+            inputParameters.RightGrid.ZTop = random.NextRoundedDouble();
+            inputParameters.RightGrid.ZBottom = random.NextRoundedDouble();
+            inputParameters.RightGrid.NumberOfHorizontalPoints = random.Next();
+            inputParameters.RightGrid.NumberOfVerticalPoints = random.Next();
+
+            using (new MacroStabilityInwardsCalculatorFactoryConfig())
+            {
+                // Call
+                MacroStabilityInwardsCalculationService.Calculate(testCalculation);
+
+                // Assert
+                UpliftVanCalculatorInput actualInput = ((TestMacroStabilityInwardsCalculatorFactory)MacroStabilityInwardsCalculatorFactory.Instance)
+                    .LastCreatedUpliftVanCalculator.Input;
+                Assert.IsTrue(actualInput.SlipPlane.GridAutomaticDetermined);
+                Assert.IsNaN(actualInput.SlipPlane.TangentZTop);
+                Assert.IsNaN(actualInput.SlipPlane.TangentZBottom);
+                Assert.IsNull(actualInput.SlipPlane.LeftGrid);
+                Assert.IsNull(actualInput.SlipPlane.RightGrid);
+            }
+        }
+
+        [Test]
         public void Calculate_CalculationRan_SetOutput()
         {
             // Setup