The Magdeburg Water Bridge (German: Kanalbrücke Magdeburg) is a navigable aqueduct in Germany, opened in October 2003 and part of the Magdeburg crossing of waterways. It connects the Elbe-Havel Canal to the Mittellandkanal, crossing over the Elbe River. It is notable for being the longest navigable aqueduct in the world, with a total length of 918 metres.
The Elbe–Havel Canal and Mittelland Canal canals had previously met near Magdeburg but on opposite sides of the Elbe, which was at a significantly lower elevation than the two canals. Ships moving between the two had to make a 12-kilometre detour, descending from the Mittelland Canal through the Rothensee boat lift into the Elbe, then sailing downstream on the river, before ascending to the Elbe-Havel Canal through Niegripp lock. Low water levels in the Elbe often prevented fully laden canal barges from making this crossing, requiring time-consuming off-loading of cargo.
The reunification of Germany and establishment of major water transport routes made the Water Bridge a priority again. Work started in 1997, with construction taking six years and costing € 500 million. The water bridge now connects Berlin’s inland harbour network with the ports along the Rhine river. The aqueduct's tough structure incorporates 24,000 tonnes of steel and 68,000 cubic meters of concrete.
In addition to the bridge, a double lock was constructed to allow vessels to descend from the level of the bridge and Mittelland Canal to that of the Elbe-Havel Canal.