Index: Application/Ringtoets/src/Application.Ringtoets.Storage/Create/PersistenceRegistry.cs
===================================================================
diff -u -r0540405a7dbabf85dc02db30c79c3c58b0faeea6 -r2651fdf110e56d0f48e416fcffc1b4922cff00a5
--- Application/Ringtoets/src/Application.Ringtoets.Storage/Create/PersistenceRegistry.cs	(.../PersistenceRegistry.cs)	(revision 0540405a7dbabf85dc02db30c79c3c58b0faeea6)
+++ Application/Ringtoets/src/Application.Ringtoets.Storage/Create/PersistenceRegistry.cs	(.../PersistenceRegistry.cs)	(revision 2651fdf110e56d0f48e416fcffc1b4922cff00a5)
@@ -45,12 +45,13 @@
         private readonly Dictionary<DikeProfileEntity, DikeProfile> dikeProfiles = CreateDictionary<DikeProfileEntity, DikeProfile>();
         private readonly Dictionary<ForeshoreProfileEntity, ForeshoreProfile> foreshoreProfiles = CreateDictionary<ForeshoreProfileEntity, ForeshoreProfile>();
         private readonly Dictionary<GrassCoverErosionInwardsCalculationEntity, GrassCoverErosionInwardsCalculation> grassCoverErosionInwardsCalculations = CreateDictionary<GrassCoverErosionInwardsCalculationEntity, GrassCoverErosionInwardsCalculation>();
-        private readonly Dictionary<HydraulicLocationEntity, HydraulicBoundaryLocation> hydraulicLocations = CreateDictionary<HydraulicLocationEntity, HydraulicBoundaryLocation>();
         private readonly Dictionary<StochasticSoilModelEntity, StochasticSoilModel> stochasticSoilModels = CreateDictionary<StochasticSoilModelEntity, StochasticSoilModel>();
         private readonly Dictionary<StochasticSoilProfileEntity, StochasticSoilProfile> stochasticSoilProfiles = CreateDictionary<StochasticSoilProfileEntity, StochasticSoilProfile>();
         private readonly Dictionary<SoilProfileEntity, PipingSoilProfile> soilProfiles = CreateDictionary<SoilProfileEntity, PipingSoilProfile>();
         private readonly Dictionary<SurfaceLineEntity, RingtoetsPipingSurfaceLine> surfaceLines = CreateDictionary<SurfaceLineEntity, RingtoetsPipingSurfaceLine>();
 
+        private readonly Dictionary<object, HydraulicBoundaryLocation> hydraulicLocations = CreateDictionary<object, HydraulicBoundaryLocation>();
+
         /// <summary>
         /// Registers a create or update operation for <paramref name="model"/> and the
         /// <paramref name="entity"/> that was constructed with the information.
@@ -137,6 +138,22 @@
         /// Registers a create or update operation for <paramref name="model"/> and the
         /// <paramref name="entity"/> that was constructed with the information.
         /// </summary>
+        /// <param name="entity">The <see cref="GrassCoverErosionOutwardsHydraulicLocationEntity"/> to be registered.</param>
+        /// <param name="model">The <see cref="HydraulicBoundaryLocation"/> to be registered.</param>
+        /// <exception cref="ArgumentNullException">Thrown when either:
+        /// <list type="bullet">
+        /// <item><paramref name="entity"/> is <c>null</c></item>
+        /// <item><paramref name="model"/> is <c>null</c></item>
+        /// </list></exception>
+        internal void Register(GrassCoverErosionOutwardsHydraulicLocationEntity entity, HydraulicBoundaryLocation model)
+        {
+            Register(hydraulicLocations, entity, model);
+        }
+
+        /// <summary>
+        /// Registers a create or update operation for <paramref name="model"/> and the
+        /// <paramref name="entity"/> that was constructed with the information.
+        /// </summary>
         /// <param name="entity">The <see cref="StochasticSoilModelEntity"/> to be registered.</param>
         /// <param name="model">The <see cref="StochasticSoilModel"/> to be registered.</param>
         /// <exception cref="ArgumentNullException">Thrown when either:
@@ -385,11 +402,11 @@
         /// has been registered for <paramref name="model"/>.</exception>
         /// <remarks>Use <see cref="Contains(HydraulicBoundaryLocation)"/> to find out
         /// whether a create/update operation has been registered for <paramref name="model"/>.</remarks>
-        internal HydraulicLocationEntity Get(HydraulicBoundaryLocation model)
+        internal T Get<T>(HydraulicBoundaryLocation model) where T : class
         {
-            return Get(hydraulicLocations, model);
+            return Get(hydraulicLocations, model) as T;
         }
-
+        
         /// <summary>
         /// Obtains the <see cref="FailureMechanismSection"/> which was registered for the
         /// given <paramref name="model"/>.