Index: src/Deltares.DSoilModel.Forms.Tests/SosSoilLayer1DControlTests.cs
===================================================================
diff -u -r883 -r956
--- src/Deltares.DSoilModel.Forms.Tests/SosSoilLayer1DControlTests.cs	(.../SosSoilLayer1DControlTests.cs)	(revision 883)
+++ src/Deltares.DSoilModel.Forms.Tests/SosSoilLayer1DControlTests.cs	(.../SosSoilLayer1DControlTests.cs)	(revision 956)
@@ -38,6 +38,7 @@
                 MinimumTopLevel = -1,
                 RemarkTopLevel = "remark testSos1",
                 IsAquifer = true,
+                WaterpressureInterpolationModel = WaterpressureInterpolationModel.Hydrostatic,
                 Soil = soil1
             };
             SoilLayer.DomainProvider = p;
@@ -61,6 +62,8 @@
             TestTextEditVisibleEnabledValue(PropertyControl, "RemarkTopLevelEdit", true, false, layer, l => l.RemarkTopLevel, "Other remark");
 
             TestCheckEditVisibleEnabledValue(PropertyControl, "AquiferCheckEdit", true, true, layer, l => l.IsAquifer, "Is aquifer", false);
+            TestLabelControlVisibleValue(PropertyControl, "InterPolationMethodLabel", true, "Interpolatie waterspanning");
+            TestComboBoxVisibleEnabledValue(PropertyControl, "InterpolationMethodEdit", true, true, layer, l => l.WaterpressureInterpolationModel, WaterpressureInterpolationModel.Hydrostatic);            
         }
 
         [Test]
Index: src/Deltares.DSoilModel.Forms/DSoilModelContext.cs
===================================================================
diff -u -r945 -r956
--- src/Deltares.DSoilModel.Forms/DSoilModelContext.cs	(.../DSoilModelContext.cs)	(revision 945)
+++ src/Deltares.DSoilModel.Forms/DSoilModelContext.cs	(.../DSoilModelContext.cs)	(revision 956)
@@ -201,7 +201,7 @@
                 if (member == layer.GetMemberName(x => x.Name) ||
                     member == layer.GetMemberName(x => x.Description) ||
                     member == layer.GetMemberName(x => x.IsAquifer) ||
-                    member == layer.GetMemberName(x => x.IsAquifer) ||
+                    member == layer.GetMemberName(x => x.WaterpressureInterpolationModel) ||
                     member == layer.GetMemberName(x => x.Height) ||
                     member == layer.GetMemberName(x => x.IsSandMedianUsed) ||
                     member == layer.GetMemberName(x => x.IsGammaSatUsed) ||
Index: src/Deltares.DSoilModel.Forms/SosSoilLayer1DControl.Designer.cs
===================================================================
diff -u -r954 -r956
--- src/Deltares.DSoilModel.Forms/SosSoilLayer1DControl.Designer.cs	(.../SosSoilLayer1DControl.Designer.cs)	(revision 954)
+++ src/Deltares.DSoilModel.Forms/SosSoilLayer1DControl.Designer.cs	(.../SosSoilLayer1DControl.Designer.cs)	(revision 956)
@@ -29,6 +29,8 @@
         private void InitializeComponent()
         {
             this.LayerGroupControl = new DevExpress.XtraEditors.GroupControl();
+            this.InterPolationMethodLabel = new DevExpress.XtraEditors.LabelControl();
+            this.InterpolationMethodEdit = new DevExpress.XtraEditors.ComboBoxEdit();
             this.RemarkTopLevelEdit = new DevExpress.XtraEditors.TextEdit();
             this.RemarkTopLevelLabel = new DevExpress.XtraEditors.LabelControl();
             this.MinDepthTopLevelEdit = new DevExpress.XtraEditors.SpinEdit();
@@ -44,10 +46,9 @@
             this.BottomEdit = new DevExpress.XtraEditors.SpinEdit();
             this.TopEdit = new DevExpress.XtraEditors.SpinEdit();
             this.BottomLabel = new DevExpress.XtraEditors.LabelControl();
-            this.InterPolationMethodLabel = new DevExpress.XtraEditors.LabelControl();
-            this.InterpolationMethodEdit = new DevExpress.XtraEditors.ComboBoxEdit();
             ((System.ComponentModel.ISupportInitialize)(this.LayerGroupControl)).BeginInit();
             this.LayerGroupControl.SuspendLayout();
+            ((System.ComponentModel.ISupportInitialize)(this.InterpolationMethodEdit.Properties)).BeginInit();
             ((System.ComponentModel.ISupportInitialize)(this.RemarkTopLevelEdit.Properties)).BeginInit();
             ((System.ComponentModel.ISupportInitialize)(this.MinDepthTopLevelEdit.Properties)).BeginInit();
             ((System.ComponentModel.ISupportInitialize)(this.MaxDepthTopLevelEdit.Properties)).BeginInit();
@@ -56,7 +57,6 @@
             ((System.ComponentModel.ISupportInitialize)(this.HeightEdit.Properties)).BeginInit();
             ((System.ComponentModel.ISupportInitialize)(this.BottomEdit.Properties)).BeginInit();
             ((System.ComponentModel.ISupportInitialize)(this.TopEdit.Properties)).BeginInit();
-            ((System.ComponentModel.ISupportInitialize)(this.InterpolationMethodEdit.Properties)).BeginInit();
             this.SuspendLayout();
             // 
             // LayerGroupControl
@@ -87,6 +87,27 @@
             this.LayerGroupControl.TabIndex = 10;
             this.LayerGroupControl.Text = "Layer";
             // 
+            // InterPolationMethodLabel
+            // 
+            this.InterPolationMethodLabel.Location = new System.Drawing.Point(20, 263);
+            this.InterPolationMethodLabel.Margin = new System.Windows.Forms.Padding(4);
+            this.InterPolationMethodLabel.Name = "InterPolationMethodLabel";
+            this.InterPolationMethodLabel.Size = new System.Drawing.Size(111, 16);
+            this.InterPolationMethodLabel.TabIndex = 71;
+            this.InterPolationMethodLabel.Text = "Interpolation model";
+            // 
+            // InterpolationMethodEdit
+            // 
+            this.InterpolationMethodEdit.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
+            this.InterpolationMethodEdit.Location = new System.Drawing.Point(180, 259);
+            this.InterpolationMethodEdit.Margin = new System.Windows.Forms.Padding(4);
+            this.InterpolationMethodEdit.Name = "InterpolationMethodEdit";
+            this.InterpolationMethodEdit.Properties.Buttons.AddRange(new DevExpress.XtraEditors.Controls.EditorButton[] {
+            new DevExpress.XtraEditors.Controls.EditorButton(DevExpress.XtraEditors.Controls.ButtonPredefines.Combo)});
+            this.InterpolationMethodEdit.Properties.TextEditStyle = DevExpress.XtraEditors.Controls.TextEditStyles.DisableTextEditor;
+            this.InterpolationMethodEdit.Size = new System.Drawing.Size(100, 22);
+            this.InterpolationMethodEdit.TabIndex = 70;
+            // 
             // RemarkTopLevelEdit
             // 
             this.RemarkTopLevelEdit.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
@@ -277,27 +298,6 @@
             this.BottomLabel.TabIndex = 8;
             this.BottomLabel.Text = "Bottom";
             // 
-            // InterPolationMethodLabel
-            // 
-            this.InterPolationMethodLabel.Location = new System.Drawing.Point(20, 263);
-            this.InterPolationMethodLabel.Margin = new System.Windows.Forms.Padding(4);
-            this.InterPolationMethodLabel.Name = "InterPolationMethodLabel";
-            this.InterPolationMethodLabel.Size = new System.Drawing.Size(21, 16);
-            this.InterPolationMethodLabel.TabIndex = 71;
-            this.InterPolationMethodLabel.Text = "Soil";
-            // 
-            // InterpolationMethodEdit
-            // 
-            this.InterpolationMethodEdit.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
-            this.InterpolationMethodEdit.Location = new System.Drawing.Point(180, 259);
-            this.InterpolationMethodEdit.Margin = new System.Windows.Forms.Padding(4);
-            this.InterpolationMethodEdit.Name = "InterpolationMethodEdit";
-            this.InterpolationMethodEdit.Properties.Buttons.AddRange(new DevExpress.XtraEditors.Controls.EditorButton[] {
-            new DevExpress.XtraEditors.Controls.EditorButton(DevExpress.XtraEditors.Controls.ButtonPredefines.Combo)});
-            this.InterpolationMethodEdit.Properties.TextEditStyle = DevExpress.XtraEditors.Controls.TextEditStyles.DisableTextEditor;
-            this.InterpolationMethodEdit.Size = new System.Drawing.Size(100, 22);
-            this.InterpolationMethodEdit.TabIndex = 70;
-            // 
             // SosSoilLayer1DControl
             // 
             this.AutoScaleDimensions = new System.Drawing.SizeF(8F, 16F);
@@ -308,6 +308,7 @@
             ((System.ComponentModel.ISupportInitialize)(this.LayerGroupControl)).EndInit();
             this.LayerGroupControl.ResumeLayout(false);
             this.LayerGroupControl.PerformLayout();
+            ((System.ComponentModel.ISupportInitialize)(this.InterpolationMethodEdit.Properties)).EndInit();
             ((System.ComponentModel.ISupportInitialize)(this.RemarkTopLevelEdit.Properties)).EndInit();
             ((System.ComponentModel.ISupportInitialize)(this.MinDepthTopLevelEdit.Properties)).EndInit();
             ((System.ComponentModel.ISupportInitialize)(this.MaxDepthTopLevelEdit.Properties)).EndInit();
@@ -316,7 +317,6 @@
             ((System.ComponentModel.ISupportInitialize)(this.HeightEdit.Properties)).EndInit();
             ((System.ComponentModel.ISupportInitialize)(this.BottomEdit.Properties)).EndInit();
             ((System.ComponentModel.ISupportInitialize)(this.TopEdit.Properties)).EndInit();
-            ((System.ComponentModel.ISupportInitialize)(this.InterpolationMethodEdit.Properties)).EndInit();
             this.ResumeLayout(false);
 
         }