The reconstruction of New Orleans refers to the process of rebuilding the city following the failure of levees and floodwalls during Hurricane Katrina on August 29, 2005. The federally built hurricane protection, called the Lake Pontchartrain and Vicinity Hurricane Protection Project failed, resulting in breaches that released tens of billions of gallons of water flooding approximately 80% of the city. The flooding remained in the city for days, in many places for weeks.
Over 204,000 homes were severely damaged or destroyed, and an estimated 200,000 vehicles were totaled. More than 800,000 citizens were displaced—the greatest displacement in the United States since the Dust Bowl of the 1930s.
Residential reconstruction was hindered by bureaucratic problems in the heavily criticized Road Home rebuilding program which was federally funded and state-managed. Critics also said that national politics factored into the program which was based on pre-storm home values, leading to disparities between rich and poor. Faith-based and volunteer agencies provided considerable supplemental relief.
The original flood protection system was redesigned and built at a cost of $14.5 billion and was 100% funded by the Army Corps through post-Katrina emergency appropriations. The new system was renamed the Hurricane & Storm Damage Risk Reduction System (HSDRRS) and is an integrated flood protection system designed to provide the Greater New Orleans area with a 100-year level of risk reduction.
Background
New Orleans geography Flooding due to rain and storms has long been an issue since the New Orleans's early settlement due to the city's location on a delta marsh, 50% of which sits below sea level. The city is surrounded by the Mississippi River to the south, Lake Pontchartrain to the north, and Lake Borgne to the east. Construction of the levees along the River began soon after the city was founded, and more extensive river levees were built as the city grew. The levees were originally designed to prevent damage caused by seasonal flooding. By summer of 2005, the 17th Street Canal and London Avenue Canal are used for drainage, to pump water from the city streets out to Lake Pontchartrain. Floodwalls (called I-walls) embedded in the canals are wide at the top and widened to at the base. The visible portion is a concrete cap on steel sheet pile that anchors to the wall. Sheet piles are interlocked steel columns, in this case at least long, with visible above ground. The wide, navigable Industrial Canal is used for shipping.
Prior to 1965, the local Orleans Levee District (OLD) built and maintained New Orleans' drainage and hurricane protection and shouldered 100% of the cost. But, heavy flooding during Hurricane Betsy brought concerns regarding flooding from hurricanes to the forefront. In the Flood Control Act of 1965, Congress directed the Army Corps have sole authority over the design and construction of the New Orleans area flood protection and the OLD shall maintain projects when completed and pay 30% of the cost. The flood protection project was called the Lake Pontchartrain and Vicinity Hurricane Protection Project. Forty years later when Katrina struck, the flood protection was between 60-90% completed with an estimated completion date of 2015, despite the initial expectation of completion within thirteen years. As of May 2005, work in Orleans Parish was certified as 90% complete, with "some work remaining" along the London Avenue Canals, and 70% complete in Jefferson Parish.
There were many predictions of hurricane risk in New Orleans before Hurricane Katrina in August, 2005. In 2001, the Houston Chronicle published a story which predicted that a severe hurricane striking New Orleans, "would strand 250,000 people or more, and probably kill one of 10 left behind as the city drowned under of water. Thousands of refugees could land in Houston." Many concerns also focused around the fact that the city's levee system was only designed for hurricanes of no greater intensity than category 3.
In addition, the region's natural defenses, the surrounding marshland and the barrier islands, have been dwindling in recent years due to human interference, mainly the energy industry.
Pre-storm preparations
On Saturday, August 27, while Katrina was a Category 3 storm gathering strength in the Gulf of Mexico, the Army Corps of Engineers Mississippi Valley Division was preparing and posturing elements from as far as Hawaii. Anticipating the possibility of a Category 5 storm placing water in New Orleans, preparations began for drainage operations.
On August 29, 2005, as Katrina made its second and third landfalls on the Louisiana-Mississippi coast, Corps District Commander, Col. Richard Wagenaar, and a team worked out of an emergency operations shelter in New Orleans. Other teams waited in the storm's path across the Gulf coast.
The Corps worked with the U.S. Coast Guard, Army National Guard and other state and federal authorities to bring in all assets available to expedite the process. "We're attempting to contract for materials, such as rock, super sand bags, cranes, etc., and also for modes of transportation like barges and helicopters, to close the gap and stop the flow of water from Lake Pontchartrain into the city," said Walter Baumy, Engineering Division chief and project manager for closing the breach.
Hurricane Katrina
Levee failures
There were 28 reported failures in the first 24 hoursStaff Writer. "Timeline: Who Knew When the Levees Broke." National Public Radio. February 10, 2006. and over 50 were reported in the ensuing days. Before dawn on Monday August 29, 2005, waves overtopped and eroded the Mississippi River-Gulf Outlet levees. At about 5:00 am, a 30-foot section of floodwall, called a "monolith," on the east side of the Inner Harbor Navigation Canal (known locally as the Industrial Canal), breached and released flood water into the adjacent Lower Ninth Ward, a dense lower to middle class neighborhood of primarily Black homeowners. By 6:30 a.m. CDT, levees along the Gulf Intracoastal Waterway, lining the south side of New Orleans East, also overtopped and breached.Van HeerdenI. Ll.Kemp G. P. Mashriqui et al. (2006). The Failure of the New Orleans Levee System during Hurricane Katrina. Final Team Louisiana Forensics Report to Louisiana Department of Transportation and Development, December 2006. Baton Rouge, LA, USA. p 71-72 The surge flooded the primarily middle to upper class Black region.
On the west edge of New Orleans, between 6 and 7:00 am, a monolith on the east side of the London Avenue Canal failed and allowed water over 10 feet deep into Fillmore Gardens, a mostly Black middle class neighborhood.Anderson C. Battjes J. Daniel D. Edge B. (2007) The New Orleans Hurricane Protection System: What Went Wrong and Why: A Report by the American Society of Civil Engineers External Review Panel. American Society of Civil Engineers, Reston, Virginia. p 55 At about 6:30 a.m., on the western edge of the city, several monoliths failed on the 17th Street Canal.Anderson C. Battjes J. Daniel D. Edge B. (2007). The New Orleans Hurricane Protection System: What Went Wrong and Why: A Report by the American Society of Civil Engineers External Review Panel. American Society of Civil Engineers, Reston, Virginia. p 47 A torrent of water blasted into Lakeview, a mainly White middle class neighborhood of homeowners.Anderson C. Battjes J. Daniel D. Edge B. (2007). The New Orleans Hurricane Protection System: What Went Wrong and Why: A Report by the American Society of Civil Engineers External Review Panel. American Society of Civil Engineers, Reston, Virginia. p 26 Local fire officials reported the breach. At about 8am, a second breach opened up in the London Avenue Canal, this one on the opposite side allowing water to flood the Lake Vista neighborhood. The Duncan and Bonnabel Pumping Stations were also reported to have suffered roof damage, and were non-functional.
At approximately 7:45 a.m. CDT, a much larger second hole opened up in the Industrial Canal just south of the initial breach. Floodwaters from the two breaches combined to submerge the entire historic Lower Ninth Ward in over 10 feet of water. Between 7 and 8:00 am, the west side of the London Avenue Canal breached, in addition to the east side, and flooded the adjacent mixed-race neighborhood of homeowners.Anderson C. Battjes J. Daniel D. Edge B. (2007). The New Orleans Hurricane Protection System: What Went Wrong and Why: A Report by the American Society of Civil Engineers External Review Panel. American Society of Civil Engineers, Reston, Virginia. p 55
The Orleans Avenue Canal midway between the 17th Street Canal and the London Avenue Canal, engineered to the same standards, and presumably put under similar stress during the hurricane, survived intact due, in part, to the presence of an unintended 100-foot-long ‘spillway,’ a section of legacy wall that was significantly lower than the adjacent floodwalls.Volume 1, USACE Interagency Performance Evaluation Taskforce, 44.
In September 2022, the Associated Press issued a style guide change to Katrina stating that reporters when writing about the storm in New Orleans should note that “…levee failures played a major role in the devastation in New Orleans. In some stories, that can be as simple as including a phrase about Hurricane Katrina’s catastrophic levee failures and flooding….”
Flooding
Army Corps' engineers initially believed that water in the 17th Street Canal overtopped the floodwall, scoured behind the wall, and caused it to collapse. However, three local fire captains confirmed with video footage that the floodwall had failed before water reached the top. The floodwall breached on the lower (New Orleans West End) side inland from the Old Hammond Highway Bridge.
There were three major breaches at the Industrial Canal; one on the upper side near the junction with MR-GO, and two on the lower side along the Lower Ninth Ward, between Florida Avenue and Claiborne Avenue. The London Avenue Canal breached in two places, on the upper side just back from Robert E. Lee Boulevard, and on the lower side a block in from the Mirabeau Avenue Bridge.
By the evening of August 29, 2005, approximately 28 levee failures were reported throughout the city. Approximately 66% to 75% of the city was now under water. The National Weather Service had predicted intense wind damage severity, but these predictions were not realized due to Katrina's path. Nonetheless, many power lines were down and the remains of trees and buildings blocked streets.
As Army Corps workers began working with the Federal Emergency Management Agency (FEMA) begin work on city cleanup and civil engineering tasks, several boats surveyed the flooded areas and blocked waterways around the city. The Army Corps used crane barges to remove barges that had been washed atop bridges and other structures.
Plans were made to begin levee work, including the placement of 3,000 pound sand bags on the 17 Street Canal. Army National Guard helicopters began assisting in this operation August 31. Meanwhile, Lake Pontchartrain started slowly draining and was expected to return to normal levels in about 36 hours.
Bridges, roadways, and railways Approximately 45 bridges were damaged by some aspect of the hurricane. Several major bridges were among the worst damaged, with the I-10 Twin Span Bridge as the most catastrophic failure with over 470 spans separated from their supports and nearly 65 fallen completely into the water. Other vital bridges damaged enough to impede traffic included the Pontchartrain Causeway, St. Louis Bay Bridge, and Biloxi Bay Bridge.