Index: DamEngine/trunk/src/Deltares.DamEngine.Interface/FillDamFromXmlInput.cs
===================================================================
diff -u -r1648 -r1687
--- DamEngine/trunk/src/Deltares.DamEngine.Interface/FillDamFromXmlInput.cs	(.../FillDamFromXmlInput.cs)	(revision 1648)
+++ DamEngine/trunk/src/Deltares.DamEngine.Interface/FillDamFromXmlInput.cs	(.../FillDamFromXmlInput.cs)	(revision 1687)
@@ -127,7 +127,7 @@
                 sensorGroup.ID = inputSensorGroup.Id;
                 foreach (var sensorId in inputSensorGroup.SensorIds)
                 {
-                    var sensor = sensorData.Sensors.FirstOrDefault(s => s.ID.Equals(sensorId.SensorId));
+                    var sensor = sensorData.Sensors.First(s => s.ID.Equals(sensorId.SensorId));
                     sensorGroup.Add(sensor);
                 }
                 sensorData.SensorGroups.Add(sensorGroup);
@@ -139,7 +139,7 @@
                 var sensorLocation = new Data.General.Sensors.SensorLocation();
                 sensorLocation.Location = locations.First(l => l.Name.Equals(inputSensorLocation.LocationId));
                 sensorLocation.Location.SensorLocation = sensorLocation;
-                sensorLocation.SensorGroup = sensorData.SensorGroups.FirstOrDefault(sg => sg.ID.Equals(inputSensorLocation.GroupId));
+                sensorLocation.SensorGroup = sensorData.SensorGroups.First(sg => sg.ID.Equals(inputSensorLocation.GroupId));
                 sensorLocation.SourceTypePl1PlLineOffsetBelowDikeTopAtPolder = ConversionHelper.ConvertToDataSourceTypeSensors(inputSensorLocation.SourceTypePl1PlLineOffsetBelowDikeTopAtPolder);
                 sensorLocation.SourceTypePl1PlLineOffsetBelowDikeToeAtPolder = ConversionHelper.ConvertToDataSourceTypeSensors(inputSensorLocation.SourceTypePl1PlLineOffsetBelowDikeToeAtPolder);
                 sensorLocation.SourceTypePl1PlLineOffsetBelowDikeTopAtRiver = ConversionHelper.ConvertToDataSourceTypeSensors(inputSensorLocation.SourceTypePl1PlLineOffsetBelowDikeTopAtRiver);
@@ -148,7 +148,6 @@
                 sensorLocation.SourceTypePl1WaterLevelAtRiver = ConversionHelper.ConvertToDataSourceTypeSensors(inputSensorLocation.SourceTypePl1WaterLevelAtRiver);
                 sensorLocation.SourceTypePl3 = ConversionHelper.ConvertToDataSourceTypeSensors(inputSensorLocation.SourceTypePl3);
                 sensorLocation.SourceTypePl4 = ConversionHelper.ConvertToDataSourceTypeSensors(inputSensorLocation.SourceTypePl4);
-                sensorLocation.SensorGroup = sensorData.SensorGroups.FirstOrDefault(sg => sg.ID.Equals(inputSensorLocation.GroupId));
                 sensorData.SensorLocations.Add(sensorLocation);
             }
         }
@@ -576,12 +575,12 @@
                     location.StabilityDesignMethod = ConversionHelper.ConvertToDamStabilityDesignMethod(designOptions.StabilityDesignMethod);
                 }
 
-                SurfaceLine2 surfaceLine = dikeSurfaceLines.FirstOrDefault(n => n.Name.Equals(inputLocation.SurfaceLineName));
+                SurfaceLine2 surfaceLine = dikeSurfaceLines.First(n => n.Name.Equals(inputLocation.SurfaceLineName));
                 location.SurfaceLine = surfaceLine;
                 Segment segment = null;
                 if (segments.Count > 0)
                 {
-                    segment = segments.FirstOrDefault(s => s.Name.Equals(inputLocation.SegmentName));
+                    segment = segments.First(s => s.Name.Equals(inputLocation.SegmentName));
                 }
                 location.Segment = segment;