--- a/src/newgrf_canal.h	Wed Jul 30 17:41:02 2008 +0000
+++ b/src/newgrf_canal.h	Wed Jul 30 18:23:12 2008 +0000
@@ -21,6 +21,7 @@
 
 struct WaterFeature {
 	const SpriteGroup *group;
+	const GRFFile *grffile;   ///< newgrf where 'group' belongs to
 	uint8 callbackmask;
 	uint8 flags;
 };