Palk Bay and Vidattaitivu Lagoon

Palk Bay is a semi-enclosed shallow water body that separates Sri Lanka from India and opens on the eastern side into the Bay of Bengal and the western side into the Gulf of Mannar. It is characterised by a number of coastal wetland habitats such as inter-tidal mudflats, sand banks and mangroves along its shores, extending into the shallow brackish water habitat of Vidattaitivu Lagoon

Parakrama Samudraya

Parakrama Samudraya is an ancient, large, shallow, man-made impoundment created for irrigation purposes by King Parakrama Bahu the Great (1153 –1186 AD) by damming the Amban Ganga. The present reservoir is a result of the three original reservoirs being connected. The reservoir is divided into three basins by chains of islands and even at high water levels these three basins maintain a distinct limnological identity. It has an extensive littoral fringe and large areas that are less than 1m in depth, which therefore provide important habitat for freshwater fishes.

Passikudah-Kalkudah Reef

Passikudah Bay contains a shallow fringing coral reef towards the outer bay with scattered coral communities within the bay, and is connected to similar reef systems further south towards Kalkudah. It is one of the best-known reef systems in the east and has been proposed as a Marine Sanctuary by NARA. Passikudah is very popular among visitors due to the calm clear waters which are ideal for swimming but is currently only rarely visited due to the volatile security situation in the area. Coral mining is a major threat to the reef and has degraded large areas of reef around Kalkudah.