A monumental project to protect the Big Easy.
Hurricane Katrina—the sixth strongest recorded Atlantic hurricane and the most costly natural disaster in U.S. history—made its third and final landfall on August 29, 2005 along the Louisiana-Mississippi border. At this time a Category 3 hurricane, Katrina's massive size brought with it record storm surges, which pummeled the coastline and inland areas. As a result, 1,836 people lost their lives and hundreds remain missing.
After levee failures in New Orleans, this surge caused catastrophic flooding within the New Orleans Metropolitan area that lasted for weeks and covered about 80 percent of the city. Once the flood waters receded, the Army Corps of Engineers began the daunting task of restoring the city's levee system.
|Additional pictures available.||Also watch a video describing the project.|
Part of that plan was the Gulf Intracoastal Waterway West Closure Complex, which today includes 11 massive pumps that will drain water from the city at a rate of 150,000 gallons per second and send it to the Gulf of Mexico. With a goal of eight of the 11 pumps operational by June 1, 2011—before the beginning of hurricane season—the complex also includes 32-foot tall, 225-foot wide metal gates that will block the water. These gates will close if a major storm threatens the New Orleans area. The closure complex will serve mainly Orleans and Jefferson Parishes.
The Gulf Intracoastal Waterway
With construction for this waterway completed in 1949, the Gulf Intracoastal Waterway (GIWW) was built to link ports, tributaries, rivers and bayous for more than 1,300 miles—from the Mexican border to Apalachicola, Fla. The section in Louisiana covers more than 300 miles and the dimensions range from 125 to 150 feet wide and 12 feet deep. The GIWW is necessary for navigation through this area but offers a storm surge easy access to the city.
The Harvey and Algiers canals meet at the GIWW. The West Closure Complex gates will prevent the storm surge from entering the Harvey and Algiers canals. However, these canals will still be full of water collected by other pump stations within the city, which is why the pumps at the West Closure Complex will pump water past the gate and into the GIWW.
Fairbanks Morse (Pentair Water) was chosen to design, develop and manage these 11 enormous pumps. It had already worked with the Army Corps of Engineers on the 17th Street pump station, and these pumps are similar to those in the 17th pump station, which move 3,600 cubic feet per second of water. However, the West Closure Complex pumps move an additional 3,850 cubic feet of water. Together, the 11 pumps will move close to 9 million gallons of water per minute.
According to Mike Wiley, GIWW team leader with Pentair - Engineered Flow, the planning for the project began years ago. “The project ran about four years, from spec stage to delivery of the final pump in December.”
These pumps are so large that the building that houses them had to be built around them, and they had to be constructed onsite. They are powered by 5,444 horsepower diesel engines. The impeller of each weighs 85,000 pounds, and the diffusers—which were custom-casted at St. Marys Foundry in St. Marys, Ohio—weigh 60,000 pounds each and are 9 feet tall. (Kincaid) To reach the construction site, each one traveled from Ohio to Milwaukee, Wis., to be machined and painted. Then it traveled from there to Harvey, La., requiring special permits and an escort because of its size for each leg of the journey.
Wiley states that these unique, enormous pieces of equipment have no equal. “All the engineering was from scratch…we had no
$1s or anything.”
One of the most difficult aspects of the project was delivery and construction. A local company, Bollinger Quick Repair was challenged with constructing the pumps once all the components were in Louisiana. “Bollinger Quick Repair, under Fairbanks Morse supervision, assembled the pumps and delivered them to the station site,” Wiley says.
How It Will Work
The pump intakes are 18 feet below water level. The pump discharge is 30 feet above the intakes on the opposite side of the station from the intakes. The gates of the West Closure Complex will close to block the storm surge from entering the Harvey and Algiers Canals and the city of New Orleans. Then the intakes will remove water from the city-side of the station and pump it over the wall into the GIWW. The project is on schedule to have eight of the 11 pumps online and ready by June 1, 2011.
To say that this station is monstrous is an understatement. Wiley has been involved with planning the station since the beginning, and when he saw it and the pumps for the first time, even he was amazed.
This feat of engineering and planning is amazing, and the added dewatering capacity may protect the New Orleans Metropolitan area should the unthinkable happen again.
Kincaid, William, “Foundry takes on huge job,” The Daily Standard, Oct. 1, 2010.
The Power of the Pumps
The specifications for each of the West Closure Complex's 11 pumps is astounding.
• 1,740 cubic feet per second (approximately 800,000 gallons per minute)
• 10-foot propeller diameter (20,000 pounds stainless steel cast)
• 12-foot diffuser diameter, 60,000-pound diffuser
• 140-inch discharge diameter (flowerpot)
• Each bowl assembly is 52 tons
• Each pump assembly is 70 tons
• Powered by 5444-horsepower diesel engine
• The gear is a right angle spiral bevel/helical design
Hurricane Katrina Stats
The sixth strongest Atlantic hurricane in recorded history, Hurricane Katrina packed a punch that impacted Alabama, Florida, Mississippi and Louisiana and caused devastating flooding in the New Orleans Metropolitan Area. Below are some of Katrina's impressive data:
• Made its final landfall on August 29, 2005
• Category 5—at its strongest
• Maximum wind speed—170 miles per hour
• Minimum central pressure—902 mb (historically, the 4th lowest)
• Wind speed at final landfall—125 miles per hour
• Central pressure at landfall—920 mb (historically, the 3rd lowest)
• Storm surge—20 to 30 feet in Mississippi
• Three landfalls—between Hallandale Beach and North Miami Beach, Fla., (category 1); at Grand Isle, La., (catgory 3); and near the Louisiana/Mississippi border (category 3)
• At least 80 percent of New Orleans was flooded on August 31, 2005
• 1.7 million residents lost power in the Gulf states
• Remained a hurricane for 150 miles inland, finally losing hurricane strength near Meridian, Miss.
Pumps & Systems, March 2011