Develops Modular Building Units for Flood Protection and Much More
As Hurricane Katrina approached New Orleans in August 2005, local officials needed something besides sand bags to fill existing gaps in their levee system. They placed HESCO Concertainer© units atop a roadway along the 17th Street Canal. The wall survived Katrina’s winds and surge while an adjacent concrete wall failed.
Then as Katrina passed New Orleans, the U.S. Army Corps of Engineers (USACE) had to make quick decisions on how to secure numerous breached levees. With Hurricane Rita entering the Gulf of Mexico just days after Katrina’s landfall, USACE deployed Concertainer units in major levees as an emergency flood control measure.
Just what are these Concertainer units? “It’s a very simple product,” says Dennis Barkmeyer, a project consultant for HESCO Bastion USA in Hammond, Louisiana. Bastion is a European term for fortification, and a Concertainer unit is a square steel-mesh cage-like container filled with earthen material. Stacked in modular fashion, it sees use all over the world in a host of civil and military applications. Government and private customers include municipalities, levee districts, city governments, emergency managers, beach projects, and private highrise condominiums suffering beach erosion.
The Concertainer was invented 15 years ago in England by Jimmy Hesselden to protect U.K. shorelines against erosion and for flood protection. A former coal miner, he did this as a backyard project, and it eventually led to the formation of HESCO Bastion Limited based in Leeds. It didn’t take long for the British military to see the potential for the product in force protection. They started using it in Bosnia during the first Persian Gulf War, placing it around the perimeters of camps and bases to protect aircraft and other machinery as well as personnel.
Then about four years ago, seeing the problems of flooding and erosion in the United States, the company decided to open HESCO Bastion USA. USACE began investigating their product for flood protection, and the East Jefferson Levee District in Jefferson Parish, Louisiana used a couple miles of it on top of an existing earthen structure. During Katrina, “The water actually came up to a foot and a half against three-foot units in some areas. And it held back the storm surge. So that was kind of the real life test, proving that it could withstand storm surges,” Barkmeyer recalls. “At the same time, we were doing a lot of coastal stabilization projects, some up in Alaska, and some sand dune reconstruction in the Florida panhandle.”
In this country, sandbags have long been the product of choice for temporary flood barriers, as they are readily available and familiar to most people. But they are labor-intensive and time-consuming to implement, and USACE has long sought to develop a better solution. They have tested the Concertainer along with sand bags in a controlled laboratory setting under conditions that simulate real-world flood fighting.
HESCO Concertainer units consist of a steel mesh framework lined with non-woven geotextile material and filled with locally available material such as rocks, rubble, sand, gravel, or soil. Each set of Concertainer units comes with joining pins for connecting individual units. When filled, the cellular structure results in a sturdy wall. The standard unit size is three feet square and comes in a set of five to create a wall 15 feet long, and in turn, these can be linked to create a wall of unlimited length.
The wires comprising the panels are welded together at an outside plant. Panels are hinged together with a helical coil system. The geotextile is a heavy-duty non-woven polypropylene material or a PVC-coated welded mesh. HESCO’s England and Louisiana facilities both assemble the units.
The units fold flat when empty, so that several fit on a standard pallet or skid. On site, Concertainer units can be quickly installed, since they are fully assembled during manufacturing and use standard backhoe loaders or similar equipment for filling.
With a construction management background, Barkmeyer oversees installations of the Concertainer units. “I meet with contractors, engineers, and users to help give product support and technical data. I’ve visited most of the major projects in the U.S. during construction.”
Coming from St. Bernard, a town south of New Orleans, Barkmeyer understands and appreciates the concept first hand. “My home had over 15 feet of water from Katrina, so to go back and do the rebuilding of the levees and have the product go into my hometown community levees is rewarding. It’s great to see the product helping slow or stop natural disasters.”
While HESCO doesn’t do the actual design of projects that use Concertainers, “We have typical drawings we provide in our brochure. We have pictures of past projects,” Barkmeyer explains. They often advise on how high the cells can be stacked. They can also supply engineering test data gathered by third parties such as USACE or engineering firms. Contractors that install their product typically have engineers on staff or hire an engineering firm. “There’s a lot of opportunity out there for engineering firms.”
Besides flood protection and military protection, many other uses have evolved for the HESCO Concertainer. They can shore up sea-ravaged coastal shorelines, stabilize embankments, and serve as mass gravity retaining walls. For fuel spill containment, the standard geotextile fabric is replaced with a fabric that contains polymers to solidify hydrocarbon on contact. They provide protection from blasts, small arms fire, and fast-moving vehicles, improving the security of major facilities such as oil refineries, power plants, or ports. Because Concertainers are conducive to earth retention and permit the growth of natural vegetation, they work well for garden landscaping. With the correct fill, they can be used to create architectural features.
In addition, Concertainer units provide wetland protection against everyday wave fetch and erosion. By serving as a natural sediment barrier, the units allow wetlands and marshlands that have been lost over the years to revitalize. They can also be planted with aquatic vegetation to help capture passing sediment.
It doesn’t stop there. In consultation with non-government organizations and aid agencies, HESCO Bastion has developed R-House, a semi-permanent building based on the Concertainer unit. R-House shelters provide protection and living space for up to eight people against the after-effects of a disaster. Using salvaged debris, they can also serve as essential buildings such as medical centers, command centers, food stores, community centers, and schools.
Adding to the list, Barkmeyer comments, “We’re starting to see a lot of residential work — homeowners that want to stabilize an embankment they may have. It’s a quick and easy way to build a retaining wall.”
Reflecting on this, Barkmeyer adds, “We’ve seen extreme growth and demand for the product since introducing it to the U.S. It’s becoming more and more popular the last couple years.”
But he realizes that flood protection comprises the core Concertainer application. “As hurricane season approaches once again, we have the Corps looking to elevate low points and armor existing flood control structures in their system.” USACE has continued to test the Concertainer units and recently decided to develop a strategic plan for stockpiling units across the United States. This new program will offer rapid flood protection to residents in a state of emergency. The future looks bright for HESCO, as they may have found a better sand bag.
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