Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/RingtoetsMacroStabilityInwardsSurfaceLine.cs
===================================================================
diff -u -r64349951de884b464e77654a723f26176c9a202c -ra940166534b3dd6e778de2e7c8e7e5241f3d3381
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/RingtoetsMacroStabilityInwardsSurfaceLine.cs	(.../RingtoetsMacroStabilityInwardsSurfaceLine.cs)	(revision 64349951de884b464e77654a723f26176c9a202c)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/RingtoetsMacroStabilityInwardsSurfaceLine.cs	(.../RingtoetsMacroStabilityInwardsSurfaceLine.cs)	(revision a940166534b3dd6e778de2e7c8e7e5241f3d3381)
@@ -27,6 +27,7 @@
 using Core.Common.Base;
 using Core.Common.Base.Data;
 using Core.Common.Base.Geometry;
+using Ringtoets.Common.Data;
 using Ringtoets.MacroStabilityInwards.Primitives.Exceptions;
 using Ringtoets.MacroStabilityInwards.Primitives.Properties;
 
@@ -35,7 +36,7 @@
     /// <summary>
     /// Definition of a surfaceline for macro stability inwards.
     /// </summary>
-    public class RingtoetsMacroStabilityInwardsSurfaceLine : Observable
+    public class RingtoetsMacroStabilityInwardsSurfaceLine : Observable, IMechanismSurfaceLine
     {
         private const int numberOfDecimalPlaces = 2;
         private Point2D[] localGeometry;