Nußdorf weir and lock

The Nussdorf weir and lock are works of hydraulic engineering located in the Viennese suburb of Nussdorf at the point where the Donaukanal leaves the Danube. The weir and lock were built following the adoption of a new law in July 1892, which also authorised the construction of the Wiener Stadtbahn and the transformation of the Donaukanal into a winter harbour.

The weir and lock in Nussdorf are commonly confused with one another, although they are actually two separate constructions built to serve the same purpose.

The weir and lock are located behind the Nussdorf station of the Emperor Franz Joseph Railway. Although they are named after a suburb in the 19th district of Vienna, Döbling, they actually fall within the jurisdiction of the 20th district, Brigittenau.

Before the construction of the weir and lock in Nussdorf, the Donaukanal was protected from floating ice and to a large extent also from flooding by the Wilhelm von Engerth’s floating barrier, the Schwimmtor. The Schwimmtor remained in service until World War I and was finally scrapped in 1945.

The weir and lock in Nussdorf and the Kaiserbadwehr (another weir) were the only hydraulic engineering works that were ever realised as part of the plan to create a harbour in the Donaukanal. Two further weir and lock arrangements had been envisaged near the Ostbahnbrücke and directly before the harbour in Freudenau.

The construction of the weir and lock was necessary to protect the new developments on the canal (the metropolitan railway, the tributary canals and later the harbour and ships) from floods and ice, but also to maintain sufficient water in the canal so that ships could pass. Wilhelm von Engerth’s Schwimmtor provided satisfactory protection from floating ice, but it only gave a very limited degree of control over the amount of water in the canal. In particular because of the need to protect the tributary canals built along the Donaukanal, it was essential that the level of water in the canal did not rise by more than 80 centimetres.

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Wikipedia