diff --git a/backend/routers/water.py b/backend/routers/water.py
index 120a0fb..5085b5f 100644
--- a/backend/routers/water.py
+++ b/backend/routers/water.py
@@ -175,7 +175,7 @@ def _water_geoms(elements: list[dict]) -> list[dict]:
             if not polygons:
                 continue
             if len(polygons) == 1:
-                geom = polygons[0]  # {'type': 'Polygon', 'coordinates': [ring]}
+                geom = {'type': 'Polygon', 'coordinates': polygons[0]}
             else:
                 # GeoJSON MultiPolygon: coordinates = список polygon.coordinates.
                 geom = {