Modern day Vedaranyam has five fresh water channels from river Cauvery draining into the swamp. The total area of the swamp is about , with width in the northwestern part and width in the western side. The Kodikarai wildlife reserve is located in the extreme eastern portion of the swamp. The northern tip of the swamp obtains continuous source of fresh, saline or brackish water during the south west monsoon and dries up during the summer season. The swamp is used for salt extraction and other marine based industries. The swamps are filled by two periodical high tides that occur during the full moon days of May and June. The swamp along with the sanctuary is the important wintering and staging area for waders and water birds.