Two locks at the beginning and end of the Alsterfleet regulate the water level of the Alster and allow boat traffic between the Alster and the Elbe: The Rathausschleuse under the Schleusenbrücke (between Rathausmarkt and Poststraße) and the Schaartorschleuse under the Schaartorbrücke. It is part of the dyke defense line and was created to protect the city of Hamburg after the storm surge in 1962. In order to be able to drain the Alster even at the Elbe flood, three pumps were installed here that can pump up to 130,000 cubic meters of water per hour from the Alster into the Elbe.
During the day, only a small amount of water is drained from the Alster in order not to jeopardize shipping. Therefore, the level of the Alster is regulated mainly at night and then decreases on average by about 10 cm. Because the water in the Alsterfleet regularly reaches high flow velocities at night, fish, shells and small organisms can not stay here. In 2014, a fish ladder was set up at the Rathausschleuse to raise fish from the Elbe to the Alster. A second fish ladder was built at the mill lock between the tidal dependency Nikolaifleet and the Mönkedammfleet, which is connected to the Alsterfleet.
July 19, 2017
The city hall lock and Schaartor lock in the mouth area of the Alster to the Elbe serve in addition to the regulation of the water levels of the shipping connection for Alster ships, barges and pleasure boats between the Elbe and the Outer Alster.The Alster locks are essential components of the worthwhile, Hamburg and its environment distinguishing river and lake landscape from the Alster and the lakes Outer Alster and Binnenalster.wikiwand.com/de/Alsterschleusen
November 5, 2019
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