NEW ORLEANS (U.S. Army Corps of Engineers, April 17, 2007) -- Outfall canal pumps are an integral part of the new Hurricane and Storm Damage Reduction System that the U.S. Army Corps of Engineers is building in New Orleans. These temporary pumps are being installed at the 17th Street, Orleans Avenue, and London Avenue outfall canals.
The pumps are called "temporary" because they are part of the temporary outfall canal closure structures that were installed immediately after Hurricane Katrina as an interim storm surge protection measure. Permanent pumps and closure structures are being designed and built, and are scheduled to be operational for the 2012 hurricane season.
The temporary pumps have one important mission. When the gated structures that are designed to prevent high levels of Lake Pontchartrain storm surge from entering the outfall canals are closed during a storm, the pumps will be activated to transport water from the outfall canals, around the gated structures, and into the lake.
The three outfall canals are critically important to New Orleans' ability to reduce potential risk to its citizens from rainfall inundation during major storm. Permanent pumping stations are used to pump accumulating rainfall from low areas into the outfall canals, where it then flows into Lake Pontchartrain. If the recently installed gated structures are closed, that water cannot flow by gravity into the lake as designed, and must be pumped by the temporary pumps to prevent water levels from rising too high within the canals.
The pumps and gates will protect the weakened floodwalls along the outfall canals, and enable inspection of those structures during storm events.
Lately, there has been inaccurate and misleading reporting by local and national media about the history, status, and capabilities of the temporary pumps. In its continuing effort to remain open and transparent, the Corps offers accurate information regarding these vital elements of the Hurricane and Storm Damage Reduction System.
"The first thing the Corps had to do was repair the breaches," said Mr. Brett Herr, Branch Chief for Regional Projects Branch in the Corps' Protection and Restoration Office. "At the same time, we were evaluating the rest of the outfall canal floodwalls to determine what kind of storm surge they could withstand."
There are 13 miles of floodwalls at the three canals.
According to Mr. Herr, the Corps, along with local and state officials, decided that the only feasible solution to restoring hurricane protection for the 2006 hurricane season would be to block the canals with temporary gated structures and pumps.
"It was within (the Corps') emergency authority to repair the damage and restore protection to that area," Mr. Herr explained. Congress provided funding with the 3rd Emergency Supplemental Appropriations Act, and the Corps began the process to design and build the temporary gates and pumps.
In January 2006, the Corps placed an order for 34 60-inch temporary pumps -- 12 for 17th Street Canal, 12 for London Avenue Canal, and 10 for Orleans Avenue Canal. The new pumps began arriving in New Orleans in late spring, before the 2006 hurricane season.
As soon as the pumps arrived, they were immediately installed by construction crews working 24 hours a day, seven days a week. In addition, the contract was modified in early summer to add six more pumps to the 17th Street Canal, bringing the total for all three canals to 40 pumps, with 18 of those for 17th Street.
"We installed the new temporary pumps as fast as we received them," said Mr. Jim St. Germain, a senior project manager in the Hurricane Protection Office. "We had crews working at the outfall canals around the clock; they were even doing some of the work at night, under lights. We were determined to make our pre-hurricane season goal, and we did."
That is not the usual means for manufacturing and installing massive equipment like these pumps. Under normal circumstances, whether for government or private industry, performance tests would be done on the equipment at the factory by the manufacturer before delivery, without observation by the government. Any operational problems would be repaired or adjusted there, and the equipment would be tested and re-tested until it meets performance expectations. When the performance is satisfactory, then the equipment would be installed in its intended location.
That's what happens under normal circumstances.
But following Katrina, the Corps did not have the luxury of working under normal circumstances. To quickly reduce the public risk, Corps personnel were placed at the factory to document manufacturer's tests, resulting in a series of reports regarding the pumps' capabilities.
"When we installed the new pumps, we knew they weren't operating to full effectiveness," said Col. Jeffrey Bedey, Hurricane Protection Office commander. "We had numerous engineering reports which told us that. But if we had done this in the traditional manner, it would have taken four to five years to get the pumps in place. Instead, we put the pumps in at the sites in a matter of months. To reduce the risk to the community for the next hurricane season, we wanted the pumps on the ground. We decided we would work out the final testing on the pumps in place."
It was reported that the new pumps vibrated when first tested at the outfall canals.
"Some of them did, but we did not see failure when the pumps vibrated," Col. Bedey said. "They would not have operated perfectly, but they would have provided pumping if we had needed it in 2006."
Col. Bedey compared the pump situation to an automobile. "When you know your car engine has a problem, you would prefer to repair it rather than drive it. But if you're in an emergency situation, you'll go ahead and drive it and get where you need to be, and then fix it when you can. That's basically what we did with the pumps."
Today, the pump problems are being solved. The pumps are being shipped weekly, and are being installed and successfully tested at the outfall canals.
"The 11 pumps that were retrofitted with stiffer springs in the hydraulic motors are performing well," said Mr. St. Germain, who directed the current field tests.
"Installation of the new pumps is going smoothly, and all 40 hydraulic pumps will be in place for this year's hurricane season," Col. Bedey said.
The Lake Pontchartrain and Vicinity Hurricane Protection Project has a long and involved history of decision-making and interaction by all levels of government, local sponsors, and the courts from the time it was first authorized in 1965 through today.
This spring, the Corps expects to release the Hurricane Protection Decision Chronology for public comment. An independent team, commissioned by the Corps, is examining all known documentation related to the development of the New Orleans-area hurricane protection system. The chronology will provide a greater understanding about how the system came to be that was in place when Hurricane Katrina made landfall on Aug. 29, 2005.
The chronology complements the work by the Independent Performance Evaluation Task Force (IPET) in the aftermath of Hurricane Katrina. The IPET study is a record of what happened during the storm and why. The chronology documents the record of decisions related to the system, including the outfall canals and the varied proposals over time as to how to best protect the canals.
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