Szczecin Lagoon (Polish:Zalew Szczeciński,German:Stettiner Haff), also known asOder Lagoon (German:Oderhaff), andPomeranian Lagoon (German:Pommersches Haff), is alagoon in theOder estuary, shared byGermany andPoland. It is separated from thePomeranian Bay of theBaltic Sea by the islands ofUsedom andWolin. The lagoon is subdivided into theKleines Haff (Polish:Mały Zalew, "small lagoon") in the West and theWielki Zalew (German:Großes Haff, "great lagoon") in the East. An ambiguous historical German name wasFrisches Haff, which later exclusively referred to theVistula Lagoon.[1]
From the South, the lagoon is fed by several arms of theOder river and smaller rivers likeZiese,Peene,Zarow,Uecker, andIna.[2] In the North, the lagoon is connected to theBaltic Sea'sBay of Pomerania with the three straitsPeenestrom,Świna andDziwna, which divide the mainland and the islands ofUsedom andWolin.
The lagoon covers an area of 687 km2, its natural depth is an average 3.8 metres, and 8.5 metres at maximum.[3] The depth of shipping channels however can exceed 10.5 metres.[3] Thus, the lagoon holds about 2.58 km3 of water.[4] The annual average water temperature is 11 °C.[4]
The Oder river and its confluences are responsible for 94% of the water loads discharged into the lagoon, amounting to an average annual 17 km3 or 540 m3 per second.[5] All other confluences contribute a combined annual 1 km3.[5] Since no reliable data for an inflow from theBaltic Sea exist, the combined inflow is an estimated 18 km3 from a catchment area of 129,000 km2, residing in the lagoon for an average 55 days before being discharged into thePomeranian Bay.[4] Thenutrients thereby transported into the lagoon have made ithyper(eu)trophic toeutrophic.[6] The straitsPeenestrom,Świna andDziwna are responsible for 17%, 69%, and 14% of the discharge, respectively.[7]
The averagesalinity is between 0.5 and 2 grams of salt per kilogram of water (approximately equivalent to 0.5 and 2parts per thousand [ppt]). Occasionally northerly winds reverse the direction of the Świna, admitting sea water from the Baltic Sea into the lagoon, raising the local salinity to 6 ppt.[5]
In the 10th century, the emerging Polish state strove for the area, but likely did not succeed with establishing control.[8]Following Poland's fragmentation, it formed part of theDuchy of Pomerania, which became part of theHoly Roman Empire of the German Nation. In the 17th century, it was ruled bySweden, but statyed part of Germany. Later on, it gradually passed to theKingdom of Prussia in the 18th and 19th century, and from 1871 was part of reunifiedGermany. In 1880, theKaiserfahrt ("Emperor's passage") channel on Usedom was opened, a water route with a depth of 10 metres connecting the lagoon with the Baltic Sea by bypassing the eastern part of the Swine, allowing large ships to enter the lagoon and the seaport of Stettin quicker and safer.
The canal, approximately 12 km long and 10 metres deep, was dug by theGerman Empire between 1874 and 1880, during the reign of the firstKaiser Wilhelm (1797–1888) after whom it was named. Also, the work resulted in a new island namedKaseburg (Karsibór) being cut off from Usedom.
After the defeat ofNazi Germany inWorld War II in 1945, the eastern part of the lagoon became part of Poland, while the western part became part ofEast Germany. TheKaiserfahrt was renamedPiast Canal, after the PolishPiast dynasty, which first included the region to Poland in the 10th century.
The German–Polish border also divides theNowe Warpno Lake nearRieth [de],Luckow.
The lagoon has served as an important fishing grounds for centuries, as a major transportation pathway since the 18th century, and as a tourist destination since the 20th century.[3]
Heringsdorf Airport onUsedom island is located on the shores of the lagoon.
The southern shore of the lagoon belongs to theAm Stettiner Haff Nature Park, its northern shore and the island of Usedom to theUsedom Island Nature Park. To the west is theAnklamer Stadtbruch Nature Reserve and, within it, theAnklamer Torfmoor, a protected wetland which is renaturalising after being used forpeat extraction.
53°48′16″N14°08′25″E / 53.80444°N 14.14028°E /53.80444; 14.14028
Tributaries of theOder | ||
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| Main tributaries of the left bank |  | |
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