Index: src/water_cmd.cpp
===================================================================
--- src/water_cmd.cpp	(revision 8496)
+++ src/water_cmd.cpp	(working copy)
@@ -40,6 +40,7 @@
 };
 
 
+static Vehicle *FindFloodableVehicleOnTile(TileIndex tile);
 static void FloodVehicle(Vehicle *v);
 
 /** Build a ship depot.
@@ -565,7 +566,7 @@
 	} else {
 		_current_player = OWNER_WATER;
 		{
-			Vehicle *v = FindVehicleOnTileZ(target, 0);
+			Vehicle *v = FindFloodableVehicleOnTile(target);
 			if (v != NULL) FloodVehicle(v);
 		}
 
@@ -576,6 +577,25 @@
 	}
 }
 
+static Vehicle *FindFloodableVehicleOnTile(TileIndex tile) {
+	if (IsBridgeTile(tile)) {
+		TileIndex end = GetOtherBridgeEnd(tile);
+		byte z = GetBridgeHeight(tile);
+		Vehicle *v;
+
+		//check the start tile first since as this is closest to the water
+		v = FindVehicleOnTileZ(tile, z);
+		if (v != NULL) return v;
+		
+		v = FindVehicleBetween(tile, end, z);
+		if (v != NULL) return v;
+
+		//check the end tile last to give fleeing vehicles a chance to escape
+		return FindVehicleOnTileZ(end, z);
+	}
+	return FindVehicleOnTileZ(tile, 0);
+}
+
 static void FloodVehicle(Vehicle *v)
 {
 	if (!(v->vehstatus & VS_CRASHED)) {