Szczecin Lagoon Szczecin Lagoon Szczecin Lagoon, Stettin Lagoon, Bay of Szczecin, or Stettin Bay (, ), also Oder lagoon (), is a lagoon in the Oder estuary, shared by Germany and Poland. It is separated from the Pomeranian Bay of the Baltic Sea by the islands of Usedom and Wolin. The lagoon is subdivided into the "Kleines Haff" (, "small lagoon") in the West and the "Wielki Zalew" (, "great lagoon") in the East. An ambiguous historical German name was "Frisches Haff", which later exclusively referred to the Vistula Lagoon. From the South, the lagoon is fed by several arms of the
Indian River Lagoon the west side of the lagoon at about 27°32'N (corresponding to Segment 11 of the model). In 2007, concerns were raised about the future of the lagoon system, especially in the southern half where frequent freshwater discharges seriously threatened water quality, decreasing the salinity needed by many fish species, and have contributed to large algae blooms promoted by water saturated with plant fertilizers. In the mid 1990s, the lagoon has been the subject of research on light penetration for photosynthesis in submerged aquatic vegetation. In 2010, of nitrogen and of phosphorus entered the lagoon. In 2011, a "superbloom" of phytoplankton