--- a/pkg/imports/gm.go	Fri Jan 11 12:01:26 2019 +0100
+++ b/pkg/imports/gm.go	Fri Jan 11 12:10:23 2019 +0100
@@ -58,6 +58,7 @@
   language_code,
   country_code,
   date_issue,
+  reference_code,
   water_level,
   predicted,
   is_waterlevel,
@@ -78,7 +79,8 @@
   $14,
   $15,
   $16,
-  $17
+  $17,
+  $18
 )
 RETURNING id`
 )
@@ -262,6 +264,13 @@
 				feedback.Warn("Invalid ISRS code %v", err)
 				continue
 			}
+			var referenceCode string
+			if wrm.Reference_code == nil {
+				feedback.Info("'Reference_code' not specified. Assuming 'ZPG'")
+				referenceCode = "ZPG"
+			} else {
+				referenceCode = *wrm.Reference_code
+			}
 			for _, measure := range wrm.Measure {
 				var unit string
 				if measure.Unit == nil {
@@ -287,6 +296,7 @@
 					msg.Identification.Language_code,
 					msg.Identification.Country_code,
 					msg.Identification.Date_issue,
+					referenceCode,
 					convert(measure.Value),
 					measure.Predicted,
 					isWaterlevel,