diff --git a/src/elrail.cpp b/src/elrail.cpp
--- a/src/elrail.cpp
+++ b/src/elrail.cpp
@@ -401,7 +401,7 @@ static void DrawCatenaryRailway(const Ti
 
 		if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile)) {
 			Track bridgetrack = GetBridgeAxis(ti->tile) == AXIS_X ? TRACK_X : TRACK_Y;
-			uint height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));
+			int height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));
 
 			if ((height <= GetTileMaxZ(ti->tile) + 1) &&
 					(i == PCPpositions[bridgetrack][0] || i == PCPpositions[bridgetrack][1])) {
@@ -438,7 +438,7 @@ static void DrawCatenaryRailway(const Ti
 
 	/* Don't draw a wire under a low bridge */
 	if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile) && !IsTransparencySet(TO_CATENARY)) {
-		uint height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));
+		int height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));
 
 		if (height <= GetTileMaxZ(ti->tile) + 1) return;
 	}