Oder Lagoon
Szczecin Lagoon, Stettin Lagoon, Bay of Szczecin, or Stettin Bay (Polish: Zalew Szczeciński, German: Stettiner Haff), also Oder lagoon (German: Oderhaff), 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 (German: Großes Haff, "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 Oder river and smaller rivers like Ziese, Peene, Zarow, Uecker, and Ina. In the North, the lagoon is connected to the Baltic Sea's Bay of Pomerania with the three straits Peenestrom, Świna and Dziwna, which divide the mainland and the islands of Usedom and Wolin .
The lagoon covers an area of 687 km², its natural depth is an average 3.8 metres, and 8.5 metres at maximum. The depth of shipping channels however can exceed 10.5 metres. Thus, the lagoon holds about 2.58 km3 of water. The annual average water temperature is 11 °C.
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