Aug. 29, 2010, marked the five-year anniversary of Hurricane Katrina’s landfall at Buras, La., in Plaquemines Parish, more than an hour south of New Orleans. The storm, which was moving with Category 5 strength less than 12 hours prior to landfall, generated a 28-foot storm surge and 55-foot waves, and the damage it wrought was unprecedented – what the Federal Emergency Management Agency (FEMA) called the costliest natural disaster ever to occur in the United States. More than 1,500 people lost their lives during the storm and subsequent floods, and $90 billion worth of property was lost or damaged. The surge and waves all but destroyed the region’s hurricane and storm protective structures, causing 50 major levee breaches; damaging 34 of 71 pumping stations; and compromising 169 of 350 miles of levees. Also contributing to the flooding was the storm’s heavy rains: 14 inches in 24 hours. In its wake, Katrina left about 80 percent of New Orleans under water – in many areas, more than 15 feet.
The federal government’s response to Katrina was carried out in two distinct phases, and the U.S. Corps of Engineers (USACE) played an integral role in both: First, to help the area recover from the damage, USACE established recovery offices in Mississippi and Louisiana to handle all emergency response missions requested by FEMA. It removed more than 200 billion gallons of water – approximately 11 percent of the volume of neighboring Lake Pontchartrain – from New Orleans in 53 days.
USACE also established Task Force Guardian immediately after Hurricane Katrina hit, with the mission of repairing and restoring New Orleans-area Hurricane and Storm Damage Risk Reduction System (HSDRRS) to pre-Katrina conditions – a task accomplished by the beginning of the 2006 hurricane season.
The Inner Harbor Navigation Canal Surge Barrier floodwall is the Corps’ largest-ever design-build project of its kind. At almost 2 miles long, this $1.3 billion project is being called the “Great Wall of Louisiana” and is scheduled to be completed by 2011. Photo courtesy of the U.S. Army Corps of Engineers
Planning a Better System
Of course, even as USACE was laboring to restore the HSDRRS to its pre-Katrina strength, the nation was struggling to come to terms with the fact that this level of protection hadn’t been enough. USACE commissioned an independent team – the Interagency Performance Evaluation Task Force, or IPET, comprising more than 150 international and national experts to analyze how the system performed or failed to perform during both Hurricane Katrina and Hurricane Rita, which struck the region almost one month after Katrina.
After the IPET issued its report, the federal government directed USACE to essentially rebuild the HSDRRS to provide protection from a 100-year flood. USACE responded promptly by forward-deploying a team within its Mississippi Valley Division: Task Force Hope.
The lessons learned from the IPET report, said Task Force Hope’s director, Karen Durham-Aguilera, were stark: “Before Katrina, people in the industry designed for the maximum probable storm – the biggest storm that had ever occurred,” she said. “But Katrina, with the amount of surge it brought in, was really of biblical proportions. Nobody even thought something like that could happen.”
Following on IPET’s findings and recommendations, Task Force Hope designed an HSDRRS that differed from the pre-Katrina system in several significant ways. Most important, the Task Force conducted computer analyses of 152 storms, both historical and potential, and placed them on literally hundreds of trajectories toward the Gulf Coast. The new system, they determined, would prepare for the combined effect of these storms, rather than the characteristics of a single historical precedent.
The new HSDRRS would also differ in its strategy, said Durham-Aguilera. “What was in place in Greater New Orleans with Katrina was called a parallel catchment system – in other words, you had interior floodwalls and you had floodgates. So instead – similar to what is being done in the Netherlands, United Kingdom, Russia, and Italy – we went to a perimeter protection, where you put in surge barriers to block most of the water that could come in from a hurricane. So the primary line of defense now is the perimeter system, with the connecting elements being the interior floodwalls, levees, and floodgates.”
In designing the system, USACE had to keep the unique urban location in mind – the system needed to have enough real estate to operate, and at the same time, keep disruptions to both homes and businesses at a minimum. Simultaneously, the project had to comply with the National Environmental Policy Act, which requires public input on the environmental impacts of the project. “That requirement alone,” said Durham-Aguilera, “has resulted in more than 300 public meetings, and we’re probably well over 500 public interactions by now.”
Five years and seven emergency congressional appropriations later, the new HSDRRS is fully funded at nearly $15 billion – many times greater than USACE’s annual Civil Works construction budget of approximately $2 billion.
“When I think about it,” said Durham-Aguilera, “to be able to get all that done – design criteria, form a cost estimate, persuade the administration and Congress to fund it, manage all the pieces to it, do the environmental process, acquire real estate, get the construction contractors – there’s really just a lot of history being made to get all that done in the space of a few years.”
The HSDRRS Today
By the summer of 2010, amidst a big surge in construction activity, the new system was about 50 percent complete, and the Greater New Orleans area had the strongest HSDRRS in its history. USACE is on track to complete the system – one of the largest engineering projects in U.S. history – by 2011.
The scope of the undertaking is difficult to comprehend, even for those witnessing it firsthand. The amount of “borrow” required to build and improve the system’s levees is about 66 million cubic yards – enough to fill the New Orleans Superdome 15 times. One of the system’s flagship projects, the Inner Harbor Navigation Canal (IHNC) Surge Barrier, at the western edge of Lake Borgne where Katrina’s surge was funneled into New Orleans at the confluence of two waterways, is the largest of its kind in the world, and USACE’s largest-ever design-build civil works construction project. When complete, the IHNC Surge Barrier, fitted with three navigation gates, will extend 2 miles across the entrance to the canal and 26 feet above the waterline. At the height of the 2010 hurricane season, 90 percent of the massive barrier wall – easily visible in satellite images – will be in place.
In August 2009, USACE began work on another flagship project, the Gulf Intracoastal Waterway West Closure Complex, a surge barrier that will reduce flood risks for west-bank portions of Jefferson, Orleans, and Plaquemines parishes by protecting 25 miles of levees, floodwalls, and pumping stations. South of the intersection of the Harvey and Algiers canals, the project will include one of the largest pumping stations in the world, capable of moving nearly 20,000 cubic feet per second when the structure is closed during storm events.
Construction on the St. Bernard Parish floodwall, Bayou Bienvenue to Bayou Dupre, Sept. 14, 2010. This floodwall will reduce risk from storm surges generated in the Mississippi River Gulf Outlet, Lake Borgne, and the Gulf of Mexico. Photo courtesy of the U.S. Army Corps of Engineers
The system’s interior floodwalls, Durham-Aguilera said, are massive in and of themselves, some as tall as 30 feet. The urban setting of the system has presented a challenge for engineers, in that it requires rolling floodgates and ramps at more than 250 vehicle-entry points – one of the most visible where the Lake Pontchartrain Causeway enters downtown New Orleans. “The bridge abutments, the floodwall, and the ramp itself will become part of the flood-protection structure,” said Durham-Aguilera. “We will have to raise the ramp where you enter the causeway to be able to accommodate that and get that floodwall under the bridge at the height we need.”
USACE is working closely with the community to keep disruptions to a minimum as the HSDRRS is built, working with the Louisiana Department of Transportation and Development to schedule road closures that will be the easiest for locals to accommodate. “We also have a 1-800 line where people, if they see something going on with construction that is really disruptive, whether it’s dust or whatever it is, they can call in,” Durham-Aguilera said. “We have people taking those calls and then seeing what we need to make things better.” But USACE’s commitment to local communities, many of which are still suffering economically, goes beyond that. Of the $9 billion in contracts awarded so far for the project, about 70 percent has been awarded to Louisiana firms and about $2.2 billion has gone directly to small businesses.
Even within the self-imposed constraints placed on its contracting, Durham-Aguilera said, Task Force Hope has been able to leverage savings and efficiencies that have paid dividends to taxpayers. “Last year, around February, we met with the steel mill industry and found out that we could take advantage of a lull in steel prices,” said Durham-Aguilera. “We could take advantage of a low price, as well as speed up the delivery, because then you wouldn’t have construction contractors trying to compete with each other to order, in this case, steel sheet piles. So we actually went out and bought steel sheet piles in bulk, set up a staging yard, set up an automated inventory system – we’ve even got businesses asking to borrow the technology. We saved about $50 million on the first contract alone. It worked so well that we went out and did another one. I think most people don’t believe a government agency can do things like that. I’m pretty amazed that we continue to look for creative ways to speed up construction, ways that are not the norm for a government public works agency.”
The Way Ahead
Despite the amazing pace of progress made on the system’s construction in the past year, Durham-Aguilera said there is still much to be done. “We’re almost finished with the real estate piece,” she said. “That’s been a huge effort, to apply the real estate easements and rights of entries that we need, but we still have just a few places left. Then the rest of it is just continuing to manage the program to the scheduled milestones, within the funding levels.”
Ultimately, the New Orleans HSDRRS will be a component of a larger effort to protect the entire Louisiana Coast. In the spring of 2010, USACE submitted a final report of its own analysis of what could be done to protect the region – the Louisiana Coastal Protection and Restoration study – to Congress and Louisiana officials. USACE also is on schedule to complete six Louisiana coastal area ecosystem restoration feasibility studies by the end of the 2010 calendar year.
Meanwhile, said Durham-Aguilera, Task Force Hope and its partners continue to make history in New Orleans. “This area is better protected than at any time in history,” she said. “It’s resulted in over 4,000 direct jobs – and then there are also all the indirect jobs, such as the guys who drive trucks to deliver fuel and stop in the nearby restaurants to eat. I could go on and on about how much this has meant to the economy of the area, as well as the risk reduction. We’re five years in, and we’re not going to back off until we’re done.”
This article first appeared in U.S. Army Corps of Engineers: Building Strong®, 2010-2011 Edition.