The Magdeburg Water Bridge (German: Wasserstraßenkreuz) is a navigable aqueduct in Germany, completed in October 2003. It connects the Elbe-Havel Canal to the Mittellandkanal ("Midland Canal"), crossing over the River Elbe. The canals had previously meet near to Magdeburg but at opposite banks across the River Elbe. It is notable for being the longest navigable aqueduct in the world, with a length of 918 metres.
Canal engineers had first conceived of joining the two waterways as far back as 1919, and by 1938 the Rothensee boat lift and bridge anchors were in place, but construction was postponed during World War II. After the Cold War split Germany, the project was put on hold indefinitely by the East German government.
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 trough structure incorporates 24,000 tonnes of steel and 68,000 cubic meters of concrete.
Until the opening of the water bridge in October 2003, ships moving between the Midland Canal and the Elbe-Havel Canal had to make a 12-kilometre zigzag detour, from the Midland Canal south-east through the Rothensee lock into the Elbe river, downstream north-east on the river, then back up to the Elbe-Havel Canal south-east through Niegripp lock.
A double lock was constructed to descend to the Elbe-Havel Canal and a single Rothensee lock was constructed at the other end of the water bridge to descend to the Elbe and the Magdeburg harbour.
The bridge site is open to visitors and includes a parking lot, bicycle and pedestrian paths and informational signs detailing the history and construction of the bridge. The bridge itself is located outside of Hohenwarthe near the city of Magdeburg and is known locally as the Wasserstrassenkreuz Magdeburg.
