Germany - Pretzien Weir

The Pretzien Weir, a sluice gate weir completed in 1875, is located at the banks of the river Elbe in the vicinity of the city of Magdeburg. The Elbe river is one of the major streams of Central Europe. Periodic floods in this largely unregulated river frequently alter the water level at Magdeburg from 0,5 meters in times of draught to 7,5 meters in times of high flooding, an enormous challenge for cities an settlements nearby. The weir is the central part of a spacious flood bypass system for the region. In the case of flooding the weir is opened, allowing a relief of up to 1.200 cubic meters per second of the river waters into a diversion canal, which equals about 1/4 of the water volume of the Elbe in times of flood. Through this canal the water bypasses the nearby cities of Magdeburg and Schönebeck and the rural areas nearby. Around 400.000 people rely on the protection of the Pretzien Weir today.