The Lake Pontchartrain Causeway is the longest continuous bridge over water in the world . It stretches for 38 km ( 24 geographical mile ) and is supported by around 9,500 concrete spile .
The southward percentage of the Lake Pontchartrain Causeway , which had two lanes , was first spread out on August 30 , 1956 , while the northbound bridge was completed in 1969 . The nosepiece was designed to link up the urban expanse of New Orleans , Louisiana , with the community of interests on the other side of Lake Pontchartrain .
Despite its tremendous size , construction of the bridgework only took14 calendar month , with assemblage - line and mass - production methods . In fact , this was the first time that such construction method acting were apply to a bridge .
During the forties and 1950s , New Orleans went through a growth jet , but access to the metropolis was stymy by the lake . To reach the city from the north shore required a lengthy , clock time - consuming drive . As such , the Greater New Orleans Expressway Commission was build to build up the Lake Pontchartrain Causeway Bridge .
The bridge was a achiever , benefitingthose who live on either side of the lake . Commute fourth dimension were dramatically dilute , while the bridge deck also offered accession for tourer in New Orleans to inspect restaurant and retail stores on the north shore .
The southbound bridge consists of 2,246 decks ( straddle ) , which are around 8.5 meters ( 28 metrical unit ) across-the-board and 17 meters ( 56 foot ) long , while the northward bride has 1,506 spans , which are typically 8.5 meters ( 28 foot ) wide and 25.6 metre ( 84 human foot ) long . Thespansinclude monolithically - cast ( meaning that all components were cast together at the same fourth dimension ) precast prestressed concrete girders , rail , and deck
The straddle on both the northward and southbound bridge are supported by precast tidy sum bents that average 27.4 meters ( 90 feet ) in length .
While the Lake Pontchartrain Causeway held the Guinness World Record for thelongest bridgeover water in the humankind , its condition was challenge in 2011 with the opening of the Qingdao Jiaozhou Bay Bridge in China . However , controversy over this led to the existence of two categories for bridgework over pee . So now the Lake Pontchartrain Causeway is recognise as the longest “ continuous ” nosepiece over water , while the Jiaozhou Bay Bridge is regarded as the long “ aggregate ” span .
