Lake Pontchartrain Causeway
The southern end of the causeway at Metairie
Carries	4 lanes of Causeway Blvd
Crosses	Lake Pontchartrain
Locale	Metairie, Louisiana and Mandeville, Louisiana
Maintained by	Greater New Orleans Expressway Commission
Design	Low-level trestle with mid-span bascule
AADT	43,000[1]
Opening date	August 30, 1956 (southbound) May 10, 1969 (northbound)
Toll	$3.00 (southbound)
Coordinates	30°11′59″N, 90°07′22″W

The Lake Pontchartrain Causeway, or the Causeway, consists of two parallel bridges that are the longest bridges in the world by total length.^[2] These parallel bridges cross Lake Pontchartrain in southern Louisiana. The longer of the two bridges is 23.87 miles (38.42 km) long. The bridges are supported by over 9,000 concrete pilings. The two bridges feature bascule spans over the navigation channel 8 miles (13 km) south of the north shore. The southern terminus of the Causeway is in Metairie, Louisiana, a suburb of New Orleans. The northern terminus is at Mandeville, Louisiana. Image File history File links Size of this preview: 800 × 534 pixelsFull resolution (1500 × 1001 pixel, file size: 281 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Lake Pontchartrains north shore at Fontainebleau State Park near Mandeville, Louisiana in 2004 Lake Pontchartrain (local English pronunciation ) (French: Lac Pontchartrain, pronounced ) is a brackish lake located in southeastern Louisiana. ... , Metairie (local pronunciations , ) is a suburb of New Orleans. ... Mandeville is a city in St. ... Steel trestle with plate girder spans A trestle is a bridge that consists of a large number of short spans, supported by splayed vertical elements and is usually for railroad use. ... Salmon Bay Bridge, Seattle, USA; a single leaf through truss with an above-deck counterweight A bascule bridge is a drawbridge with a counterweight that continuously balances the span, or leaf, throughout the entire upward swing in providing clearance for boat traffic. ... Annual average daily traffic, abbrevated AADT, is a term used primarily in transportation planning and transportation engineering. ... is the 242nd day of the year (243rd in leap years) in the Gregorian calendar. ... Year 1956 (MCMLVI) was a leap year starting on Sunday (link will display full calendar) of the Gregorian calendar. ... is the 130th day of the year (131st in leap years) in the Gregorian calendar. ... Also: 1969 (Stargate SG-1) episode. ... Map of Earth showing lines of latitude (horizontally) and longitude (vertically), Eckert VI projection; large version (pdf, 1. ... The Pontchartrain Expressway should not be confused with the Lake Pontchartrain Causeway which connects the north and south shores of Lake Pontchartrain. ... Wikimedia Commons has media related to: Interstate 10 Interstate 10 (abbreviated I-10) is the southernmost east-west, coast-to-coast interstate highway in the United States. ... U.S. Highway 90 Business (officially U.S. Highway 90-Z[1]) is a business route of U.S. Highway 90 in and near New Orleans, Louisiana, United States. ... NOLA redirects here. ... The Hindenburgdamm rail causeway across the Wadden Sea to the island of Sylt in Schleswig-Holstein, Germany In modern usage, a causeway is a road or railway elevated by a bank, usually across a broad body of water or wetland. ... volcanic rock. ... Lake Pontchartrains north shore at Fontainebleau State Park near Mandeville, Louisiana in 2004 Lake Pontchartrain (local English pronunciation ) (French: Lac Pontchartrain, pronounced ) is a brackish lake located in southeastern Louisiana. ... Official language(s) de jure: none de facto: English & French Capital Baton Rouge Largest city New Orleans [1] Area  Ranked 31st  - Total 51,885 sq mi (134,382 km²)  - Width 130 miles (210 km)  - Length 379 miles (610 km)  - % water 16  - Latitude 29°N to 33°N  - Longitude 89°W... Salmon Bay Bridge, Seattle, USA; a single leaf through truss with an above-deck counterweight A bascule bridge is a drawbridge with a counterweight that continuously balances the span, or leaf, throughout the entire upward swing in providing clearance for boat traffic. ... , Metairie (local pronunciations , ) is a suburb of New Orleans. ... NOLA redirects here. ... Mandeville is a city in St. ...

History

The idea of a bridge spanning Lake Pontchartrain dates back to the early 19th Century and Bernard de Mandeville, 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 the Louisiana Legislature created what is now the Causeway Commission. Bernard de Mandeville (1670 – 1733), was a philosopher, political economist and satirist. ...

The original Causeway was a two-lane span that opened in 1956 at a cost of $30.7 million. A parallel two-lane span, 1/100th of a mile (20 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. Year 1956 (MCMLVI) was a leap year starting on Sunday (link will display full calendar) of the Gregorian calendar. ... is the 130th day of the year (131st in leap years) in the Gregorian calendar. ... Also: 1969 (Stargate SG-1) episode. ... This article is about the year. ...

The opening of the Causeway boosted the fortunes of small North Shore communities by reducing drive time into New Orleans by up to 50 minutes, bringing the North Shore into the New Orleans metropolitan area. Prior to the Causeway, residents of St. Tammany Parish had to go around the lake, either the east side via the Rigolets Bridge on U.S. Route 90 near Slidell, Louisiana or on the west side via U.S. Route 51 through Manchac, Louisiana. The New Orleans Metropolitan Area, consisting of the Greater New Orleans region and three addtional parishes which share the perimeter of Lake Ponchartrain, is the largest metropolitan area in the U.S. state of Louisiana, centered around the city of New Orleans. ... The Fort Pike Bridge (also known as the Rigolets Bridge) carries U.S. Route 90 across the Rigolets on the eastern side of Lake Pontchartrain between New Orleans and Slidell, Louisiana. ... U.S. Route 90 is an east-west United States highway. ... , Slidell is a city in St. ... U.S. Highway 51 is a north-south United States highway that runs for 1,286 miles (2,070 km) from northern Wisconsin to the western suburbs of New Orleans, Louisiana. ... Manchac is a small town in Tangipahoa Parish, Louisiana. ...

After Hurricane Katrina on August 29th, 2005, videos collected showed damage to the bridge, but the damage was mostly on the unused turnaround on the older southbound span; the structural foundations remained intact. The Causeways have never sustained major damage of any sort due to hurricanes and other natural occurrences, a rarity in the causeway community. The existing fiber optic cable plant was blown out of the tray but remained intact per OTDR analysis. With the I-10 Twin Span Bridge severely damaged, the Causeway was used as a major route for recovery teams staying in highlands to the North to get into New Orleans. The Causeway reopened first to emergency traffic and then to the general public, with tolls suspended, on September 19, 2005. Tolls were reinstated by mid-October. This article is about the Atlantic hurricane of 2005. ... is the 241st day of the year (242nd in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... The I-10 Twin Span Bridge, known locally as the Twin Spans, consists of two parallel trestle bridges. ... is the 262nd day of the year (263rd in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ...

Accidents

The Causeway has been struck by barges on three occasions that have caused structural damage resulting in the collapse of portions of the roadway.^[3]

• January 17, 1960, an empty barge struck the bridge in heavy fog in the morning hours. Two of the Causeway's 52 foot spans collapsed and a third was damaged. There were no fatalities.
• June 16, 1964, a tugboat pushing two barges collides with the bridge in the early morning causing 4 spans to collapse into the lake. A Continental Trailways bus fell into the lake killing 6 people.
• August 1, 1974, several barges collided with the new northbound span collapsing several spans and sending several vehicles into the water, killing 3 people.

is the 17th day of the year in the Gregorian calendar. ... Year 1960 (MCMLX) was a leap year starting on Friday (link will display full calendar) of the Gregorian calendar. ... is the 167th day of the year (168th in leap years) in the Gregorian calendar. ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... is the 213th day of the year (214th in leap years) in the Gregorian calendar. ... Year 1974 (MCMLXXIV) was a common year starting on Tuesday (link will display full calendar) of the 1974 Gregorian calendar. ...

Third span plans

Heading south on the Causeway toward New Orleans

In 2002, the Causeway Commission discussed the construction of a third span, before ultimately deciding to renovate the existing spans as studies showed traffic growth leveling off. The third span was estimated to have cost $400 million, which by 2006 had risen to $800-900 million. In the aftermath of Hurricane Katrina, traffic has grown to 40,000 vehicles per day as the population of Northshore parishes have rapidly increased. A 1992 traffic study predicted the traffic capacity of the current spans would be exceeded in 2007; an estimate that was later revised to an earlier date and rendered useless by Katrina related population shifts. In early March 2006, General Manager Robert Lambert acknowledged that the Commission may revisit the plan for a third span. Lambert cited the increase in traffic and the need for better evacuations routes to the north as the leading reasons for reexamining the need for a new span. The proposed third span would be east of the current northbound span and include two travel lanes and a full right-hand shoulder. The current southbound span would also be fitted with a full shoulder. The current northbound span would then be used as a one lane with full shoulder reversible roadway to correspond with peak travel hours.^[4] Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ...

Trivia

• Both spans have a 65-mph speed limit 24 hours per day. This was increased from 55 mph in 2004 in order to increase safety on the span and reduce travel time by 4 minutes, however the southbound span has night time sight line issues at the span's rises, requiring a speed limit of 55 mph over the humps. The Causeway Commission is studying the expense of lighting the rises on the southbound and possibly the northbound span.^[1][5]

See also

• List of bridges in the United States
• List of bridges by length
• Prestressed concrete

Bridges in the United States is a link page for any notable bridge in the United States of America. ... Donghai Bridge, longest cross-sea bridge This is a list of the worlds bridges longer than 1 km (3281 ft) sorted by their full length above land or water. ... Traditional reinforced concrete is based on the use of steel reinforcement bars, rebar, inside poured concrete. ...

References

The New Orleans Times-Picayune is the major daily newspaper serving New Orleans, Louisiana. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... is the 53rd day of the year in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... is the 53rd day of the year in the Gregorian calendar. ...

External links

• The Causeway website
• Google Maps satellite image