Clearing Out the Water and Waste in the Big Easy

One of the most devastating byproducts of Hurricane Katrina was the flood waters it left in its wake. As Chip Dupuy, project manager for Cajun Constructors, Inc., points out, the flooding in New Orleans was unlike any experienced in other regions.

"The majority of the time, when you see floods in other areas of the country, they dry up on their own as the waters recede or drain off," he notes. "The problem with New Orleans is there's no place for the water to drain off. It's just a big bowl surrounded by levees. So it had to be pumped out."

The process of "unwatering" the city seemed a nearly impossible task. Yet, a handful of contractors, including Cajun Constructors, rose to the challenge. Thanks to their efforts, what was expected to take months took just four weeks to complete.

Tackling the flood

Cajun Constructors is no stranger to dewatering operations. This large public works and industrial contractor, based in Baton Rouge, LA, is frequently involved in infrastructure projects, including water and waste water treatment plant construction.

"In the type of work we do, we're always dealing with ground water that we have to get rid of in excavations; or we have water or sewer waste we have to deal with on a temporary basis when we do renovation or tie-in work in a water or sewer plant," says Dupuy. "So the process of pumping water or sewage is something we knew how to do."

However, when it came to unwatering New Orleans' flooded areas, Cajun Constructors found a situation far beyond any it had previously encountered. "We had to take what we knew from past experience and just escalate it, or kick it up a notch, to a whole new volume of work," says Dupuy.

From various sources, Cajun Constructors rented 125 pumps ranging from 12 to 42 in. Models included 31 Godwin DPC300 Dri-Prime diesel-powered trash pumps with 12-in. openings, as well as 21 Thompson 12-in. centrifugal dry priming pumps, plus one 20-in., two 24-in. and five 18-in. units. Other similar-sized and larger pumps were rented from Service Pump & Compressor (a Hertz Equipment company), Rain for Rent and Andress Walsh.

"The reason we went with several different pump vendors was the immediate need and the volume of water to pump out of New Orleans," Dupuy states. It essentially boiled down to which suppliers could provide the right size pumps the fastest.

Once the necessary equipment was procured, the real challenges began. "There were no facilities there — you had to be self supported," says Dupuy of conditions in the city. "There was no power, running water, housing, hospitals or food easily available for personnel. And then there was the threat of looters and snipers and whatever else. We had to come fully equipped with our own support facilities and security to protect and support the workers for a 24-hour-a-day operation."

Setting up the pumps also proved a logistical nightmare. "When we got there, we placed the pumps wherever there was dry land and as close to the deepest water source we could find," Dupuy explains. "Strategically, we placed them around flood walls and drainage canals where we could find the deepest water source and didn't have too long a discharge to install."

Getting to these dry spots wasn't easy. "Initially, some of the roads were under water and we had to mobilize some of the equipment by water instead of by land," says Dupuy. This meant using marine equipment in place of trucks to transport pumps and construction equipment.

Setup and tear-down of pumps was also a nearly continuous process. Pumps were often set up in the morning, then moved again the same afternoon or the next day.

In addition, the pumps had to be continually fueled and serviced. However, because of the flooding and lack of electricity, local fuel suppliers were out of business. The solution came in the form of a fuel barge, which Cajun used as backup storage. "We kept over 100,000 gal. of fuel in the barge so we could place it into a fuel truck and transport it to fuel pods around where the pumps were located," says Dupuy. "When the fuel barge was low, it went upriver to a facility for refilling."