Lake Pontchartrain is a brackish estuary located in southeastern Louisiana in the United States. It covers an area of 630 square miles (1,600 km2) with an average depth of 12 to 14 feet. Some shipping channels are kept deeper through dredging. It is roughly oval in shape, about 40 miles (64 km) from west to east and 24 miles (39 km) from south to north.
The Mississippi River–Gulf Outlet Canal is a 76 mi (122 km) channel constructed by the United States Army Corps of Engineers at the direction of Congress in the mid-20th century that provided a shorter route between the Gulf of Mexico and New Orleans' inner harbor Industrial Canal via the Intracoastal Waterway. In 2005, the MRGO channeled Hurricane Katrina's storm surge into the heart of Greater New Orleans, contributing significantly to the subsequent multiple engineering failures experienced by the region's hurricane protection network. In the aftermath the channel was closed. A permanent storm surge barrier was constructed in the MRGO in 2009, and the channel has been closed to maritime shipping.
The Ninth Ward or 9th Ward is a distinctive region of New Orleans, Louisiana, which is located in the easternmost downriver portion of the city. It is geographically the largest of the 17 Wards of New Orleans. On the south, the Ninth Ward is bounded by the Mississippi River. On the western or "upriver" side, the Ninth Ward is bounded by Franklin Avenue, then Almonaster Avenue, then People's Avenue. From the north end of People's Avenue the boundary continues on a straight line north to Lake Pontchartrain; this line is the boundary between the Ninth and the city's Eighth Ward. The Lake forms the north and northeastern end of the ward. St. Bernard Parish is the boundary to the southeast, Lake Borgne farther southeast and east, and the end of Orleans Parish to the east at the Rigolets.
Hurricane preparedness in New Orleans has been an issue since the city's early settlement because of its location.
From 1890 through 2006, the Orleans Levee Board was the body of commissioners that oversaw the Orleans Levee District (OLD) which supervised the levee and floodwall system in Orleans Parish, Louisiana. The role of the OLB has changed over time. Prior to Hurricane Betsy in 1965, the OLB developed land and sold it to raise money to build and improve levees. After 1965, Congress directed the Army Corps of Engineers to be responsible for design and construction of the hurricane flood protection system enveloping New Orleans.
The Southeast Louisiana Urban Flood Control Project is a flood control project by the US Army Corps of Engineers to protect the New Orleans district from flooding due to potential storms, hurricanes, or water surges. It was established in 1996.
The 17th Street Canal is the largest and most important drainage canal in the city of New Orleans. Operating with Pump Station 6, it moves water into Lake Pontchartrain. The canal, along with the Orleans Canal and the London Avenue Canal, form the New Orleans Outfall Canals. The 17th Street Canal forms a significant portion of the boundary between the city of New Orleans and Metairie, Louisiana. The canal has also been known as the Metairie Outlet Canal and the Upperline Canal.
The London Avenue Canal is a drainage canal in New Orleans, Louisiana, used for pumping rain water into Lake Pontchartrain. The canal runs through the 7th Ward of New Orleans from the Gentilly area to the Lakefront. It is one of the three main drainage canals responsible for draining rainwater from the main basin of New Orleans. The London Avenue Canal's flood walls built atop earthen levees breached on both sides during Hurricane Katrina in 2005.
Though Hurricane Katrina did not deal the city of New Orleans a direct hit on August 29, 2005, the associated storm surge precipitated catastrophic failures of the levees and flood walls. The Mississippi River Gulf Outlet ("MR-GO") breached its levees in approximately 15 places. The major levee breaches in the city include the 17th Street Canal levee, the London Avenue Canal, and the wide, navigable Industrial Canal, which left approximately 80% of the city flooded.
On Monday, August 29, 2005, there were over 50 failures of the levees and flood walls protecting New Orleans, Louisiana, and its suburbs following passage of Hurricane Katrina. The failures caused flooding in 80% of New Orleans and all of St. Bernard Parish. In New Orleans alone, 134,000 housing units — 70% of all occupied units — suffered damage from Hurricane Katrina and the subsequent flooding.
A flood barrier, surge barrier or storm surge barrier is a specific type of floodgate, designed to prevent a storm surge or spring tide from flooding the protected area behind the barrier. A surge barrier is almost always part of a larger flood protection system consisting of floodwalls, levees, and other constructions and natural geographical features.
Drainage in New Orleans, Louisiana, has been a major concern since the founding of the city in the early 18th century, remaining an important factor in the history of New Orleans today. The central portion of metropolitan New Orleans is fairly unusual in that it is almost completely surrounded by water: Lake Pontchartrain to the north, Lake Borgne to the east, wetlands to the east and west, and the Mississippi River to the south. Half of the land area between these bodies of water is at or below sea level, and no longer has a natural outlet for flowing surface water. As such, virtually all rainfall occurring within this area must be removed through either evapotranspiration or pumping. Thus, flood threats to metropolitan New Orleans include the Mississippi River, Lake Pontchartrain, canals throughout the city, and natural rainfall. Artificial levees have been built to keep out rising river and lake waters but have had the negative effect of keeping rainfall in, and have failed on numerous occasions.
Pontchartrain Park is a historically registered neighborhood of the city of New Orleans. A subdistrict of the Gentilly District Area, its boundaries as defined by the City Planning Commission are: Leon C. Simon Drive to the north, the Industrial Canal to the east, Dreux Avenue to the south and Peoples Avenue to the west.
The I-10 Twin Span Bridge, a nearly 5.5-mile (8.9 km) causeway officially known as the Frank Davis "Naturally N'Awlins" Memorial Bridge, consists of two parallel trestle bridges. These parallel bridges cross the eastern end of Lake Pontchartrain in southern Louisiana from New Orleans to Slidell. The current bridge spans were constructed in the second half of the 2000s after the original bridges were extensively damaged by Hurricane Katrina on August 29, 2005. The first span opened to eastbound traffic on July 9, 2009. On April 7, 2010, the second span was opened to traffic and the old twin spans were permanently closed to traffic.
The Flood Control Act of 1965, Title II of Pub.L. 89–298, was enacted on October 27, 1965, by the 89th Congress and authorized the United States Army Corps of Engineers to design and construct numerous flood control projects including the Lake Pontchartrain and Vicinity, Louisiana Hurricane Protection Project in the New Orleans region of south Louisiana.
The Inner Harbor Navigation Canal Lake Borgne Surge Barrier is a storm surge barrier constructed near the confluence of and across the Gulf Intracoastal Waterway (GIWW) and the Mississippi River Gulf Outlet (MRGO) near New Orleans. The barrier runs generally north-south from a point just east of Michoud Canal on the north bank of the GIWW and just south of the existing Bayou Bienvenue flood control structure.
The Gulf Intracoastal Waterway West Closure Complex is a part of the New Orleans Drainage System; it consists of a navigable floodgate, a pumping station, flood walls, sluice gates, foreshore protection, and an earthen levee. The complex was designed to reduce risk for residences and businesses in the project area from a storm surge associated with a tropical event, with an intensity that has a one percent chance of occurring in any given year. This project was operated for the first time on August 29, 2012, in response to Hurricane Isaac.
The Inner Harbor Navigation Canal (IHNC) Seabrook Floodgate Structure is a flood barrier in the Industrial Canal in New Orleans, Louisiana. The floodgate is designed to protect the Industrial Canal and the surrounding areas from a storm surge from Lake Pontchartrain. It consists of two 50-foot (15 m) wide vertical lift gates and a 95-foot (29 m) wide sector gate.
There are three outfall canals in New Orleans, Louisiana – the 17th Street, Orleans Avenue and London Avenue canals. These canals are a critical element of New Orleans’ flood control system, serving as drainage conduits for much of the city. There are 13 miles (21 km) of levees and floodwalls that line the sides of the canals. The 17th Street Canal is the largest and most important drainage canal and is capable of conveying more water than the Orleans Avenue and London Avenue Canals combined.
The greater New Orleans Hurricane & Storm Damage Risk Reduction System (HSDRRS) is an infrastructure systems in southern Louisiana which seeks to provide the greater New Orleans area a 100-year level of risk reduction, meaning reduced risk from a storm surge that has a 1% chance of occurring or being exceeded in any given year. In 2019, the Army Corps of Engineers announced that due to increased rate of sea level rise and continued sinking of soil the levee system would no longer offer original planned levels of protection as early as the year 2023.