Lake Pontchartrain Causeway

The Lake Pontchartrain Causeway is 23.83 miles long, composed of two parallel bridges crossing Lake Pontchartrain from Metairie to Mandeville. It holds the Guinness World Record for longest continuous span over water in the world. The bridges are supported by 9,500 concrete pilings. A bascule bridge spans the navigation channel 8 miles south of the north shore. The idea of a bridge across Lake Pontchartrain dates to the early 19th century and Bernard de Marigny, the founder of Mandeville. He started a ferry service that operated into the mid-1930s. The modern causeway started to take form in 1948 when Ernest M. Loëb Jr. envisioned the project. The Louisiana Legislature created what is now the Causeway Commission. The Louisiana Bridge Company was formed to construct the bridge, and James E. Walters Sr. was appointed to direct the project. The original causeway was a two-lane span, 23.86 miles long. It opened in 1956 at a cost of $46 million. A parallel two-lane span opened on May 10, 1969, at a cost of $30 million. On June 16, 1964, six people died when barges tore a gap in the bridge and a bus plunged into the lake. The opening of the causeway reduced drive time into New Orleans by up to 50 minutes. Prior to the causeway, residents of St. Tammany Parish used either the Maestri Bridge on U.S. Highway 11 or the Rigolets Bridge on US 90, both near Slidell; or on the west side, via US 51 through Manchac. Since its construction, the causeway has operated as a toll bridge. After Hurricane Katrina on August 29, 2005, the structural foundations remained intact. The causeways have never sustained major damage of any sort from hurricanes or other natural occurrences. The causeway reopened to the general public on September 19, 2005. The bridge was designated as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers in 2013.