diff --git a/src/bridge_gui.cpp b/src/bridge_gui.cpp
index d1baacdf0a..b18582e9b6 100644
--- a/src/bridge_gui.cpp
+++ b/src/bridge_gui.cpp
@@ -147,7 +147,7 @@ void ShowBuildBridgeWindow(TileIndex start, TileIndex end, TransportType transpo
 {
 	DeleteWindowById(WC_BUILD_BRIDGE, 0);
 
-	_bridgedata.type = ((transport_type << 7) | bridge_type) << 8; //prepare the parameter for use only once
+	_bridgedata.type = (transport_type << 15) | (bridge_type << 8); //prepare the parameter for use only once
 	_bridgedata.start_tile = start;
 	_bridgedata.end_tile = end;
 
diff --git a/src/gui.h b/src/gui.h
index b361409f3e..ab93aec7a5 100644
--- a/src/gui.h
+++ b/src/gui.h
@@ -106,7 +106,7 @@ void SetFiosType(const byte fiostype);
 extern const TextColour _fios_colors[];
 
 /* bridge_gui.cpp */
-void ShowBuildBridgeWindow(TileIndex start, TileIndex end, TransportType Transport_type, byte type);
+void ShowBuildBridgeWindow(TileIndex start, TileIndex end, TransportType transport_type, byte bridge_type);
 
 void ShowBuildIndustryWindow();
 void ShowMusicWindow();