The lagoon is fed by a number of small rivers, including Nay Aru (Mullaitivu). It is linked to the sea by a narrow channel to the south that is very often blocked by a sand bar. The lagoon's water is brackish.
S.W. Kotagama, Leonard Pinto and Jayampathi L. Samarakoon. "Sri Lanka"(PDF). Wetlands International. Archived from the original(PDF) on 18 April 2012. Retrieved 23 May 2009.