diff --git a/src/tunnelbridge_cmd.cpp b/src/tunnelbridge_cmd.cpp
index cbbd31d4b7..86e0f25af1 100644
--- a/src/tunnelbridge_cmd.cpp
+++ b/src/tunnelbridge_cmd.cpp
@@ -2244,7 +2244,7 @@ void SubtractRoadTunnelBridgeInfrastructure(TileIndex begin, TileIndex end) {
 }
 
 static void UpdateRailTunnelBridgeInfrastructure(Company *c, TileIndex begin, TileIndex end, bool add) {
-	const uint middle_len = 2 * GetTunnelBridgeLength(begin, end) * TUNNELBRIDGE_TRACKBIT_FACTOR;
+	const uint middle_len = GetTunnelBridgeLength(begin, end) * TUNNELBRIDGE_TRACKBIT_FACTOR;
 
 	if (c != NULL) {
 		uint primary_count = middle_len + GetTunnelBridgeHeadOnlyPrimaryRailInfrastructureCount(begin) + GetTunnelBridgeHeadOnlyPrimaryRailInfrastructureCount(end);
diff --git a/src/tunnelbridge_map.h b/src/tunnelbridge_map.h
index 2159bcc131..7693412428 100644
--- a/src/tunnelbridge_map.h
+++ b/src/tunnelbridge_map.h
@@ -223,6 +223,7 @@ static inline bool HasAcrossTunnelBridgeReservation(TileIndex t)
  */
 static inline uint GetTunnelBridgeHeadOnlyRailInfrastructureCountFromTrackBits(TrackBits bits)
 {
+	if (!bits) return 0;
 	uint pieces = CountBits(bits);
 	if (TracksOverlap(bits)) pieces *= pieces;
 	return (TUNNELBRIDGE_TRACKBIT_FACTOR / 2) * (1 + pieces);