The idea of a bridge spanning Lake Pontchartrain dates back to the early 19th Century and Bernard de Marigny, the founder of Mandeville. He started a ferry service that continued to operate into the mid 1930s. In the 1920s, a proposal called for the creation of artificial islands that would then be linked by a series of bridges. The financing for this plan would come from selling homesites on the islands. The modern Causeway started to take form in 1948 when Ernest M Loeb Jr envisioned the project. Due to his lobbying and vision the Louisiana Legislature created what is now the Causeway Commission. The Louisiana Bridge Company was formed to construct the bridge, who in turn appointed James E. Walters, Sr to direct the project.
The original Causeway was a two-lane span, measuring 23.86 miles (38.40 km) in length, that opened in 1956 at a cost of $30.7 million. A parallel two-lane span, 1/100th of a mile (15 m) longer than the original, opened on May 10, 1969 at a cost of $26 million. The Causeway has always been a toll bridge. Until 1999, tolls were collected from traffic going in each direction. To alleviate congestion on the south shore, toll collections were eliminated on the northbound span. The standard tolls for cars changed from $1.50 in each direction to a $3.00 toll collected on the North Shore for southbound traffic only.
Google Mapの地図や航空写真で見ると、ポンチャートレイン湖を南北に一本の線が貫く感じでとても美しい。
このようにポンチャートレイン湖コーズウェイは「連続して水上に架かる橋("continuous")」でありそのカテゴリーでは現在でも世界最長なのだが、2011年に竣工された青島膠州湾大橋(Jiaozhou Bay Bridge、42.5km)が「連続しない水上に架かる橋("aggregate")」として上回ることになった。
Jiaozhou Bay Bridge is a roadway bridge in eastern China's Shandong province. It transects Jiaozhou Bay, connecting Huangdao District, the city of Qingdao and Hongdao Island (the bridge is "T" shaped with 3 entry/exit points, see map). Opened on 30 June 2011, it reduces the road distance between Qingdao and Huangdao. The bridge opened at the same time as the nearby Qing-Huang Tunnel, both part of the Jiaozhou Bay Connection Project.
Jiaozhou Bay Bridge is 42.5 kilometres (26.4 mi) long, making it according to Guinness World Records the world's longest bridge over water (aggregate length) as of July 2011. The longest bridge over water "continuous length" is the Lake Pontchartrain Causeway, the difference being the latter runs continuously over water while Jiaozhou Bay Bridge has parts over land. It is estimated Jiaozhou Bay Bridge is over water for 25.5 kilometres (15.8 mi).
The bridge is located between Shanghai and Nanjing in East China’s Jiangsu province. It includes a 9-kilometre long (5.6 mi) section over water that crosses Yangcheng Lake in Suzhou. It was completed in 2010 and opened in 2011. Employing 10,000 people, construction took four years and cost about $8.5 billion. Danyang?Kunshan Grand Bridge currently holds the Guinness World Record for the longest bridge in the world in any category as of June 2011.
