diff --git a/src/ship_cmd.cpp b/src/ship_cmd.cpp
--- a/src/ship_cmd.cpp
+++ b/src/ship_cmd.cpp
@@ -624,7 +624,7 @@ bool IsShipDestinationTile(TileIndex til
 	for (DiagDirection d = DIAGDIR_BEGIN; d != DIAGDIR_END; d++) {
 		TileIndex t = tile + TileOffsByDiagDir(d);
 		if (!IsValidTile(t)) continue;
-		if (IsDockTile(t) && GetStationIndex(t) == station && IsValidDockingDirectionForDock(t, d)) return true;
+		if (IsDockTile(t) && GetStationIndex(t) == station && IsDockWaterPart(t)) return true;
 		if (IsTileType(t, MP_INDUSTRY)) {
 			const Industry *i = Industry::GetByTile(t);
 			if (i->neutral_station != nullptr && i->neutral_station->index == station) return true;
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -2741,20 +2741,6 @@ void ClearDockingTilesCheckingNeighbours
 }
 
 /**
- * Check if a dock tile can be docked from the given direction.
- * @param t Tile index of dock.
- * @param d DiagDirection adjacent to dock being tested. (unused)
- * @return True iff the dock can be docked from the given direction.
- */
-bool IsValidDockingDirectionForDock(TileIndex t, DiagDirection d)
-{
-	assert(IsDockTile(t));
-
-	StationGfx gfx = GetStationGfx(t);
-	return gfx >= GFX_DOCK_BASE_WATER_PART;
-}
-
-/**
  * Find the part of a dock that is land-based
  * @param t Dock tile to find land part of
  * @return tile of land part of dock
diff --git a/src/station_func.h b/src/station_func.h
--- a/src/station_func.h
+++ b/src/station_func.h
@@ -40,7 +40,6 @@ void DeleteOilRig(TileIndex t);
 void UpdateStationDockingTiles(Station *st);
 void RemoveDockingTile(TileIndex t);
 void ClearDockingTilesCheckingNeighbours(TileIndex tile);
-bool IsValidDockingDirectionForDock(TileIndex t, DiagDirection d);
 
 /* Check if a rail station tile is traversable. */
 bool IsStationTileBlocked(TileIndex tile);
diff --git a/src/station_map.h b/src/station_map.h
--- a/src/station_map.h
+++ b/src/station_map.h
@@ -435,30 +435,13 @@ static inline DiagDirection GetDockDirec
 }
 
 /**
- * Get the tileoffset from this tile a ship should target to get to this dock.
- * @param t Tile to query
- * @pre IsTileType(t, MP_STATION)
- * @pre IsBuoy(t) || IsOilRig(t) || IsDock(t)
- * @return The offset from this tile that should be used as destination for ships.
+ * Check whether a dock tile is the tile on water.
  */
-static inline TileIndexDiffC GetDockOffset(Tile t)
+static inline bool IsDockWaterPart(Tile t)
 {
-	static const TileIndexDiffC buoy_offset = {0, 0};
-	static const TileIndexDiffC oilrig_offset = {2, 0};
-	static const TileIndexDiffC dock_offset[DIAGDIR_END] = {
-		{-2,  0},
-		{ 0,  2},
-		{ 2,  0},
-		{ 0, -2},
-	};
-	assert(IsTileType(t, MP_STATION));
-
-	if (IsBuoy(t)) return buoy_offset;
-	if (IsOilRig(t)) return oilrig_offset;
-
-	assert(IsDock(t));
-
-	return dock_offset[GetDockDirection(t)];
+	assert(IsDockTile(t));
+	StationGfx gfx = GetStationGfx(t);
+	return gfx >= GFX_DOCK_BASE_WATER_PART;
 }
 
 /**
diff --git a/src/water_cmd.cpp b/src/water_cmd.cpp
--- a/src/water_cmd.cpp
+++ b/src/water_cmd.cpp
@@ -186,7 +186,7 @@ void CheckForDockingTile(TileIndex t)
 		TileIndex tile = t + TileOffsByDiagDir(d);
 		if (!IsValidTile(tile)) continue;
 
-		if (IsDockTile(tile) && IsValidDockingDirectionForDock(tile, d)) {
+		if (IsDockTile(tile) && IsDockWaterPart(tile)) {
 			Station::GetByTile(tile)->docking_station.Add(t);
 			SetDockingTile(t, true);
 		}