diff --git a/src/object_cmd.cpp b/src/object_cmd.cpp
index 0e500ebf97..13cf402738 100644
--- a/src/object_cmd.cpp
+++ b/src/object_cmd.cpp
@@ -33,6 +33,7 @@
 #include "newgrf_debug.h"
 #include "vehicle_func.h"
 #include "station_func.h"
+#include "pathfinder/water_regions.h"
 
 #include "table/strings.h"
 #include "table/object_land.h"
@@ -169,6 +170,7 @@ void BuildObject(ObjectType type, TileIndex tile, CompanyID owner, Town *town, u
 
 	for (TileIndex t : ta) {
 		if (IsWaterTile(t)) ClearNeighbourNonFloodingStates(t);
+		if (HasTileWaterGround(t)) InvalidateWaterRegion(t);
 		WaterClass wc = (IsWaterTile(t) ? GetWaterClass(t) : WATER_CLASS_INVALID);
 		/* Update company infrastructure counts for objects build on canals owned by nobody. */
 		if (wc == WATER_CLASS_CANAL && owner != OWNER_NONE && (IsTileOwner(t, OWNER_NONE) || IsTileOwner(t, OWNER_WATER))) {
diff --git a/src/rail_cmd.cpp b/src/rail_cmd.cpp
index de124719b3..6d9725a827 100644
--- a/src/rail_cmd.cpp
+++ b/src/rail_cmd.cpp
@@ -40,6 +40,7 @@
 #include "news_func.h"
 #include "scope.h"
 #include "newgrf_newsignals.h"
+#include "pathfinder/water_regions.h"
 
 #include "table/strings.h"
 #include "table/railtypes.h"
@@ -3133,6 +3134,7 @@ static CommandCost ClearTile_Track(TileIndex tile, DoCommandFlag flags)
 					bool remove = IsDockingTile(tile);
 					DoClearSquare(tile);
 					if (remove) RemoveDockingTile(tile);
+					InvalidateWaterRegion(tile);
 				}
 				cost.AddCost(_price[PR_CLEAR_WATER]);
 			}