Water bridges are bridge-like structures that carry navigable waterway canals over other rivers, valleys, railways or roads. Small ships and boats ply on these waterways. The most popular water bridge is the Magdeburg Water Bridge in Germany, the longest and the most impressive in the world. Although aqueducts has been used for supplying cities with water since centuries, they were not generally used for traffic until the 17th century when modern canal systems started to appear. The 662-metre long aqueduct carrying the Canal latéral à la Loire over the River Loire was built in 1896, and remained the longest navigable aqueduct in the world until the 21st century, when the Magdeburg Water Bridge in Germany took the title.
Here are three of the most unusual and magnificent water bridges around the world.
Magdeburg Water Bridge
The Magdeburg Water Bridge in Germany deserve special mention. 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. At 918 meters, it’s the longest navigable aqueduct in the world.
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.
Pontcysyllte Aqueduct
The Pontcysyllte Aqueduct, in Wrexham County Borough in Britain, was built between 1795 and 1805 to carry the Ellesmere Canal over the valley of the River Dee to link the coal mines of Denbighshire to the national canal system during the Industrial Revolution. It was one of the world's greatest engineering achievements of the time. For more than 200 years, it is the longest and highest aqueduct in Britain, and currently a World Heritage Site.
The aqueduct is 307 meter long, 3.4 meter wide and 1.60 meter deep, and forms a part of an 18 km long aqueduct system. It consists of a cast iron trough supported 38 meter above the river on iron arched ribs carried on nineteen hollow masonry piers. The use of both cast and wrought iron in the aqueduct enabled the construction of arches that were light and strong, producing an overall effect that is both monumental and elegant.
The economic influence of the canal for the region was considerable during the first half of the 19th century, enabling the rapid development of coal extraction, metal working, limestone quarries, and the production of lime. The slate quarries of the Welsh mountains and agriculture also benefited from the canal. Today, the canal no longer moves coal and limestone cargoes, but is a popular spot for tourists. Since 1954 the canal has been managed and maintained in a navigable condition by British Waterways.
Barton Swing Aqueduct
The Barton Swing Aqueduct is a moveable water bridge in Barton upon Irwell in Greater Manchester, England, that carries the Bridgewater Canal across the Manchester Ship Canal. The swinging action allows large vessels using the Manchester Ship Canal to pass underneath and smaller narrow boats to cross over the top. When large vessels need to pass along the Ship Canal, the 1,450-tonne and 100 meter long iron trough is rotated 90 degrees. A gate at each end of the trough retains around 800 tonnes of water; further gates on each bank retain water in their adjacent stretches of canal. A similar swing bridge, but for road traffic, lies adjacent to, and upstream of, the Barton Swing Aqueduct.
The aqueduct, which is the first and only swing aqueduct in the world is considered a major feat of Victorian civil engineering. Designed by Sir Edward Leader Williams and built by Andrew Handyside of Derby, the swing bridge opened in 1894 and remains in regular use.
Previously, the aqueduct crossing over River Irwell was a rigid stone structure that prevented new ships of larger dimension to pass underneath the bridge. A swinging bridge became a necessity.
The swing aqueduct (left) in the closed position, showing the Bridgewater canal crossing over the Ship Canal; the Barton Road Swing Bridge is on the right. Photo credit
Other notable water bridges, not included in this Top3 list are the Avon Aqueduct - the longest and tallest canal aqueduct in Scotland and the second-longest in the United Kingdom, after the Pontcysyllte Aqueduct, and the Briare Aqueduct – which was the longest navigable aqueduct in the World until the opening of the Magdeburg Water Bridge. If you are interested, look them up on Google. If you are visiting the United Kingdom, spare a day to visit these remarkable achievements in civil engineering.
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