Index: Ringtoets/Common/src/Ringtoets.Common.Data/AssessmentSection/BackgroundData.cs
===================================================================
diff -u -rd2d96421974b56eb204dd8f756748aa582da0874 -r68e06c08cb60c1c42e5c3b03fd3af070748a6bca
--- Ringtoets/Common/src/Ringtoets.Common.Data/AssessmentSection/BackgroundData.cs	(.../BackgroundData.cs)	(revision d2d96421974b56eb204dd8f756748aa582da0874)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/AssessmentSection/BackgroundData.cs	(.../BackgroundData.cs)	(revision 68e06c08cb60c1c42e5c3b03fd3af070748a6bca)
@@ -20,7 +20,6 @@
 // All rights reserved.
 
 using System;
-using System.Collections.Generic;
 using Core.Common.Base;
 using Core.Common.Base.Data;
 using Ringtoets.Common.Data.Properties;
@@ -46,7 +45,14 @@
         {
             IsVisible = true;
             transparency = new RoundedDouble(transparencyNumberOfDecimals);
-            Parameters = new Dictionary<string, string>();
+            Parameters = new FilteredKeyDictionary<string, string>(
+                new[]
+                {
+                    BackgroundDataIdentifiers.SourceCapabilitiesUrl,
+                    BackgroundDataIdentifiers.SelectedCapabilityIdentifier,
+                    BackgroundDataIdentifiers.PreferredFormat,
+                    BackgroundDataIdentifiers.WellKnownTileSource
+                });
         }
 
         /// <summary>
@@ -97,6 +103,6 @@
         /// <summary>
         /// Gets the parameters that are configured for a background map data.
         /// </summary>
-        public IDictionary<string, string> Parameters { get; }
+        public FilteredKeyDictionary<string, string> Parameters { get; }
     }
 }
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