Vistula Lagoon of the Ests". Over three hundred years later, in the first half of the 13th Century, the name of Vistula Lagoon occurs in deeds issued by Teutonic Order in Latin version as Mare Recens (1246 - "mare" - a pool or lake or sea and "recens" - fresh) in contrast to the contemporary name for the Baltic Sea - Mare Salsum (Salty Sea). Then in 1251 we find record about Mare Recens et Neriam (Frisches Haff and Frische Nehrung, now Vistula Spit) and finally in 1288 Recenti Mari Hab (Haff) which as one can see corresponds with later German "Frisches
Koggala Lagoon streams, Mudiyansege-ela stream and Thithagalla-ela stream, is the second largest freshwater inflow. Heen-ela stream contributes a minor to the freshwater inflow In addition to above four streams, Kahanda-ela stream, Gurukanda-ela stream and Thelambu-ela stream are also contributors for freshwater inflows but are presently abandoned with overgrown vegetation. The only outlet of the lagoon is Pol-oya located at the southeast corner; a narrow long canal, which connects the lagoon with the Indian Ocean. The lagoon has a hydro-catchment area of approximately . Various land use practices exist in the catchment, which mainly includes small-scale fishing industry and paddy farming. The Koggala