Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators.Tests/KernelWrappers/MacroStabilityCommon/PlLinesToWaternetConverterTests.cs
===================================================================
diff -u -r5941 -r5994
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators.Tests/KernelWrappers/MacroStabilityCommon/PlLinesToWaternetConverterTests.cs	(.../PlLinesToWaternetConverterTests.cs)	(revision 5941)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators.Tests/KernelWrappers/MacroStabilityCommon/PlLinesToWaternetConverterTests.cs	(.../PlLinesToWaternetConverterTests.cs)	(revision 5994)
@@ -120,33 +120,12 @@
     }
 
     [Test]
-    [TestCase(0)]
-    [TestCase(0.01)]
-    [TestCase(10)]
-    public void GivenPlLinesFullyDefinedAtOrBelowBottomSoil1DProfile_WhenCreatingWaternetBasedOnPlLinesAnd1DSoilProfile_ThenReturnsEmptyWaternet(double offsetFromBottomOfProfile)
+    public void GivenPlLinesWithoutPoints_WhenCreatingWaternetBasedOnPlLinesAnd1DSoilProfile_ThenReturnsEmptyWaternet()
     {
         // Setup
         SoilProfile1D soilProfile = FactoryForSoilProfiles.CreateSoilProfile1DWithTwoClustersOfInBetweenAquifers(out SurfaceLine2 surfaceLine);
-        double bottomLevel = soilProfile.BottomLevel;
-        double plLineZCoordinate = bottomLevel - offsetFromBottomOfProfile;
-
         var plLines = new PlLines();
-        PlLine plLine = plLines.Lines[PlLineType.Pl1];
-        plLine.Points.Add(new PlLinePoint(leftCoordinate, plLineZCoordinate));
-        plLine.Points.Add(new PlLinePoint(rightCoordinate, plLineZCoordinate));
 
-        plLine = plLines.Lines[PlLineType.Pl2];
-        plLine.Points.Add(new PlLinePoint(leftCoordinate, plLineZCoordinate));
-        plLine.Points.Add(new PlLinePoint(rightCoordinate, plLineZCoordinate));
-
-        plLine = plLines.Lines[PlLineType.Pl3];
-        plLine.Points.Add(new PlLinePoint(leftCoordinate, plLineZCoordinate));
-        plLine.Points.Add(new PlLinePoint(rightCoordinate, plLineZCoordinate));
-
-        plLine = plLines.Lines[PlLineType.Pl4];
-        plLine.Points.Add(new PlLinePoint(leftCoordinate, plLineZCoordinate));
-        plLine.Points.Add(new PlLinePoint(rightCoordinate, plLineZCoordinate));
-
         // Call
         Waternet waternet = PlLinesToWaternetConverter.CreateWaternetBasedOnPlLines(plLines, soilProfile, surfaceLine, penetrationLength, IntrusionVerticalWaterPressureType.Standard);
 
Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/PlLinesToWaternetConverter.cs
===================================================================
diff -u -r5941 -r5994
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/PlLinesToWaternetConverter.cs	(.../PlLinesToWaternetConverter.cs)	(revision 5941)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/PlLinesToWaternetConverter.cs	(.../PlLinesToWaternetConverter.cs)	(revision 5994)
@@ -74,7 +74,7 @@
 
         PlLine plLine = plLines.Lines[PlLineType.Pl1];
         var headLine = CreateLine<HeadLine>(plLine, headLine1Name);
-        if (plLine != null && !IsBelowSoilProfile(soilProfile1D, plLine))
+        if (plLine != null && plLine.Points.Count != 0)
         {
             waternet.PhreaticLine = CreateLine<PhreaticLine>(plLine, headLine1Name);
             WaternetLine waternetLine = CreateWaternetLineForPhreaticLine(soilProfile1D, surfaceLine, plLine, xLeft, xRight, pressureType);
@@ -90,7 +90,7 @@
         
         plLine = plLines.Lines[PlLineType.Pl2];
         headLine = CreateLine<HeadLine>(plLine, headLine2Name);
-        if (headLine != null && !IsBelowSoilProfile(soilProfile1DDikeToeAtPolder, plLine) &&
+        if (headLine != null && plLine.Points.Count != 0 &&
             pressureType == IntrusionVerticalWaterPressureType.SemiTimeDependent && penetrationLength > 0)
         {
             waternet.HeadLineList.Add(headLine);
@@ -103,7 +103,7 @@
 
         plLine = plLines.Lines[PlLineType.Pl3];
         headLine = CreateLine<HeadLine>(plLine, headLine3Name);
-        if (headLine != null && !IsBelowSoilProfile(soilProfile1DDikeToeAtPolder, plLine) &&
+        if (headLine != null && plLine.Points.Count != 0 &&
             pressureType != IntrusionVerticalWaterPressureType.FullHydroStatic)
         {
             waternet.HeadLineList.Add(headLine);
@@ -142,7 +142,7 @@
         
         var waternet = new Waternet();
         PlLine plLine = plLines.Lines[PlLineType.Pl1];
-        if (plLine != null)
+        if (plLine != null && plLine.Points.Count != 0)
         {
             var headLine = CreateLine<HeadLine>(plLine, headLine1Name);
             waternet.PhreaticLine = CreateLine<PhreaticLine>(plLine, headLine1Name);
@@ -153,7 +153,7 @@
         }
 
         plLine = plLines.Lines[PlLineType.Pl2];
-        if (plLine != null && pressureType == IntrusionVerticalWaterPressureType.SemiTimeDependent && penetrationLength > 0)
+        if (plLine != null && plLine.Points.Count != 0 && pressureType == IntrusionVerticalWaterPressureType.SemiTimeDependent && penetrationLength > 0)
         {
             var headLine = CreateLine<HeadLine>(plLine, headLine2Name);
             waternet.HeadLineList.Add(headLine);
@@ -164,7 +164,7 @@
         }
 
         plLine = plLines.Lines[PlLineType.Pl3];
-        if (plLine != null && pressureType != IntrusionVerticalWaterPressureType.FullHydroStatic)
+        if (plLine != null && plLine.Points.Count != 0 && pressureType != IntrusionVerticalWaterPressureType.FullHydroStatic)
         {
             var headLine = CreateLine<HeadLine>(plLine, headLine3Name);
             waternet.HeadLineList.Add(headLine);
@@ -193,17 +193,13 @@
     
     private static void CreateWaternetLinesForInBetweenAquifers(Waternet waternet, SoilProfile1D soilProfile1D, double xLeft, double xRight, PlLine plLine4, IntrusionVerticalWaterPressureType? pressureType)
     {
-        var headLine = CreateLine<HeadLine>(plLine4, headLine4Name);
-        if (headLine == null || IsBelowSoilProfile(soilProfile1D, plLine4))
+        if (plLine4 == null || plLine4.Points.Count == 0 || soilProfile1D.GetInBetweenAquiferClusters == null
+            || pressureType == IntrusionVerticalWaterPressureType.FullHydroStatic)
         {
             return;
         }
-
-        if (soilProfile1D.GetInBetweenAquiferClusters == null || pressureType == IntrusionVerticalWaterPressureType.FullHydroStatic)
-        {
-            return;
-        }
-
+        
+        var headLine = CreateLine<HeadLine>(plLine4, headLine4Name);
         waternet.HeadLineList.Add(headLine);
         var number = 0;
         foreach ((SoilLayer1D, SoilLayer1D) inBetweenAquiferCluster in soilProfile1D.GetInBetweenAquiferClusters.Where(layer => layer is { Item1: not null, Item2: not null }))
@@ -226,16 +222,11 @@
     private static void CreateWaternetLinesForInBetweenAquifers(Waternet waternet, SoilProfile2D soilProfile, SurfaceLine2 surfaceLine, PlLine plLine4,
                                                                 IntrusionVerticalWaterPressureType? pressureType)
     {
-        if (plLine4 == null)
+        if (plLine4 == null || plLine4.Points.Count == 0 || pressureType == IntrusionVerticalWaterPressureType.FullHydroStatic)
         {
             return;
         }
 
-        if (pressureType == IntrusionVerticalWaterPressureType.FullHydroStatic)
-        {
-            return;
-        }
-
         SoilProfile2DHelper.DetermineInBetweenAquifersLayerBoundaryPoints(soilProfile, out List<GeometryPointString> inBetweenAquiferUpperCoordinates, 
                                                                           out List<GeometryPointString> inBetweenAquiferLowerCoordinates);
 
@@ -480,12 +471,6 @@
 
         return waternetLine;
     }
-    
-    private static bool IsBelowSoilProfile(SoilProfile1D soilProfile, PlLine line)
-    {
-        double bottomSoilProfileLevel = soilProfile.BottomLevel;
-        return line.Points.Any(point => point.Z <= bottomSoilProfileLevel);
-    }
 
     /// <summary>
     /// Throws when the pl lines object is not assigned.