IHNC Lake Borgne Surge Barrier
Encyclopedia
The Inner Harbor Navigation Canal Lake Borgne Surge Barrier is a storm surge barrier under construction 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. Navigation gates will be constructed where the barrier crosses the GIWW and Bayou Bienvenue to reduce the risk of storm surge
coming from Lake Borgne
and/or the Gulf of Mexico
. Another navigation gate (Seabrook Floodgate) is planned for the Seabrook vicinity where the IHNC meets Lake Pontchartrain
to block a storm surge from entering the IHNC from the lake.
in 2006. The barrier is designed to reduce the risk of storm damage to some of the region's most vulnerable areas - New Orleans East, metro New Orleans
, the 9th Ward
, and St. Bernard Parish
. This project aims to protect these areas from storm surge coming from the Gulf of Mexico
and Lake Borgne
.
contract to Shaw Environmental & Infrastructure for the Lake Borgne Surge Barrier, making this project the largest design-build
civil works project in Corps history. It is highly unusual for a civil works project to be designed and constructed simultaneously. The expedited process is necessary, however, given the compressed timeframe to achieve 100-year level of risk reduction
in 2011.
In October 2008, the New Orleans District Commander signed the Tier 2 portion of the Individual Environmental Report (IER), which investigated alternative alignments and designs within the location range identified by Tier 1 and explained the impacts of these alignments and footprints, construction materials and methods, and other design details. After the completion of the IER, a Notice to Proceed was issued to Shaw.
In December 2008 the Corps held a groundbreaking
ceremony to mark the start of test pile driving. Construction of the barrier floodwall began on May 9, 2009. On 21 October 2009 the last of the 1,271 main piles was driven.
In the Gulf Intracoastal Waterway navigation channel two gates are constructed. One gate is closed with two sector gates, the other gate can be closed with a swing barge gate, comparable to a caisson
. In the Bayou Bienvenue navigation channel a vertical lift gate is constructed for recreational crafts and shrimpers.
Gulf Intracoastal Waterway
The Gulf Intracoastal Waterway is the portion of the Intracoastal Waterway located along the Gulf Coast of the United States. It is a navigable inland waterway running approximately 1700 kilometers from Carrabelle, Florida, to Brownsville, Texas.The waterway provides a channel with a controlling...
(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
Bayou Bienvenue
Bayou Bienvenue is a bayou in southeastern Louisiana. It runs along the political border between Orleans Parish and St. Bernard Parish to the east of New Orleans....
flood control
Flood control
In communications, flood control is a feature of many communication protocols designed to prevent overwhelming of a destination receiver. Such controls can be implemented either in software or in hardware, and will often request that the message be resent after the receiver has finished...
structure. Navigation gates will be constructed where the barrier crosses the GIWW and Bayou Bienvenue to reduce the risk of storm surge
Storm surge
A storm surge is an offshore rise of water associated with a low pressure weather system, typically tropical cyclones and strong extratropical cyclones. Storm surges are caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up higher than the ordinary sea...
coming from Lake Borgne
Lake Borgne
Lake Borgne is a lagoon in eastern Louisiana of the Gulf of Mexico. Due to coastal erosion, it is no longer actually a lake but rather an arm of the Gulf of Mexico. Its name comes from the French word borgne, which means "one-eyed".-Geography:...
and/or the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
. Another navigation gate (Seabrook Floodgate) is planned for the Seabrook vicinity where the IHNC meets Lake Pontchartrain
Lake Pontchartrain
Lake Pontchartrain is a brackish estuary located in southeastern Louisiana. It is the second-largest inland saltwater body of water in the United States, after the Great Salt Lake in Utah, and the largest lake in Louisiana. As an estuary, Pontchartrain is not a true lake.It covers an area of with...
to block a storm surge from entering the IHNC from the lake.
Purpose
The Inner Harbor Navigation Canal (IHNC) surge barrier was authorized by CongressUnited States Congress
The United States Congress is the bicameral legislature of the federal government of the United States, consisting of the Senate and the House of Representatives. The Congress meets in the United States Capitol in Washington, D.C....
in 2006. The barrier is designed to reduce the risk of storm damage to some of the region's most vulnerable areas - New Orleans East, metro New Orleans
New Orleans metropolitan area
New Orleans–Metairie–Kenner, or the Greater New Orleans Region is a metropolitan area designated by the United States Census encompassing seven parishes in the state of Louisiana, centering on the city of New Orleans...
, the 9th Ward
Ninth Ward of New Orleans
The Ninth Ward or 9th Ward is a distinctive region of New Orleans, Louisiana that is located in the easternmost downriver portion of the city. It is geographically the largest of the 17 Wards of New Orleans....
, and St. Bernard Parish
St. Bernard Parish, Louisiana
St. Bernard Parish is a parish located southeast of New Orleans in the U.S. state of Louisiana. The parish seat is Chalmette, the largest city in the parish. As of 2000, its population was 67,229. It has been ranked the fastest-growing county in the United States from 2007 to 2008 by the U.S....
. This project aims to protect these areas from storm surge coming from the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
and Lake Borgne
Lake Borgne
Lake Borgne is a lagoon in eastern Louisiana of the Gulf of Mexico. Due to coastal erosion, it is no longer actually a lake but rather an arm of the Gulf of Mexico. Its name comes from the French word borgne, which means "one-eyed".-Geography:...
.
Status
In April 2008, the Corps awarded a constructionConstruction
In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of human multitasking...
contract to Shaw Environmental & Infrastructure for the Lake Borgne Surge Barrier, making this project the largest design-build
Design-Build
Design-build is a project delivery system used in the construction industry. It is a method to deliver a project in which the design and construction services are contracted by a single entity known as the design–builder or design–build contractor...
civil works project in Corps history. It is highly unusual for a civil works project to be designed and constructed simultaneously. The expedited process is necessary, however, given the compressed timeframe to achieve 100-year level of risk reduction
Risk reduction
Risk reduction may refer to:* Absolute risk reduction or Relative risk reduction, statistical descriptors of an intervention.* Risk management* Safety Integrity Level* Hedge...
in 2011.
In October 2008, the New Orleans District Commander signed the Tier 2 portion of the Individual Environmental Report (IER), which investigated alternative alignments and designs within the location range identified by Tier 1 and explained the impacts of these alignments and footprints, construction materials and methods, and other design details. After the completion of the IER, a Notice to Proceed was issued to Shaw.
In December 2008 the Corps held a groundbreaking
Groundbreaking
Groundbreaking, also known as cutting, sod-cutting, turning the first sod or a sod-turning ceremony, is a traditional ceremony in many cultures that celebrates the first day of construction for a building or other project. Such ceremonies are often attended by dignitaries such as politicians and...
ceremony to mark the start of test pile driving. Construction of the barrier floodwall began on May 9, 2009. On 21 October 2009 the last of the 1,271 main piles was driven.
Construction
The main barrier consists of 1,271 concrete piles 66 inches (1.7 m) across and 144 feet (43.9 m) long, weighing 96 tonnes each. Behind those piles steel piles are driven under 45 degrees. On top of these pilings prefabricated concrete sections are placed.In the Gulf Intracoastal Waterway navigation channel two gates are constructed. One gate is closed with two sector gates, the other gate can be closed with a swing barge gate, comparable to a caisson
Caisson (engineering)
In geotechnical engineering, a caisson is a retaining, watertight structure used, for example, to work on the foundations of a bridge pier, for the construction of a concrete dam, or for the repair of ships. These are constructed such that the water can be pumped out, keeping the working...
. In the Bayou Bienvenue navigation channel a vertical lift gate is constructed for recreational crafts and shrimpers.
Features
- Concrete floodwall with navigation gates at Bayou Bienvenue and the GIWW
- Navigation gate at Seabrook vicinity
- MarshMarshIn geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
enhancement with dredged organic material - As organic material is dredged from waterways in preparation for new construction, it will be deposited in nearby wetlands habitats to enhance environmental conditions