calm blue waters of grevelingenmeer lake with a red buoy rubbing

netherlands bay blue bouy buoy calm coast color concept control daylight entrance equipment europe float isolated lake lifebuoy marine maritime marker metal motion nature nautical navigation nederland object ocean plastic prevention protection river route safe safety sail sea seascape security shipping sign signal surface symbol tranquil transportation warning water waterway wave waters grevelingenmeer red rubbing light waves sunny day zonnemaire zeeland