Preparing For The Worst
New Orleans sewage treatment plant addresses emergency preparedness
In 2005, Hurricane Katrina left the East Bank Sewage Treatment plant in New Orleans, La., completely submerged for weeks. Officials know there might be “another big one” someday and they must be well equipped. WWD Assistant Editor Kristin Muckerheide recently spoke with Sewerage & Water Board General Superintendent Joseph C. Becker, P.E., to discuss how the plant prepares for the worst.
Kristin Muckerheide: What is the East Bank Sewage Treatment Plant’s history?
Joe Becker: The plant was brought online in 1980 and has the capacity to provide primary and secondary treatment for 122 million gal a day in dry weather. The plant consists of bar screens, grit removal, pure oxygen activated sludge, final clarification, disinfection and incineration.
The sewer system consists of 1,150 miles of gravity-fed pipe on the east bank. With only 66 sewage pumping stations, the East Bank sewage system relies a great deal on gravity to flow toward the treatment facility.
Muckerheide: What population size does it serve?
Becker: The East Bank Sewage Treatment plant serves a population of 325,000 residents. This is about 100,000 fewer residents than we had in 2005 before Hurricane Katrina. While this population reduction has decreased the flow to the plant, it has also dramatically [affected] revenue. The Sewerage & Water Board is completely dependent upon money generated from the monthly usage bills for water and sewer operations and capital improvements. This reduction in income has resulted in significant funding reductions for activities at the East Bank Plant.
Muckerheide: How does the plant handle specific treatment challenges?
Becker: The Sewerage & Water Board and Veolia Water, its plant operator, have adapted to overcome significant obstacles in recent years. Despite these challenges, the plant has maintained an excellent service record over the last 20 years. One of the most obvious challenges faced by the East Bank Plant were damages sustained as a result of Hurricane Katrina. In addition to damages sustained from high winds associated with tornadoes and hurricanes, Hurricane Katrina pushed a wall of water in front of it that submerged everything in its path. The plant is protected with a 14 ft berm around the facility but was hit with an 18-ft wave on the morning of Aug. 29, 2005. That wave completely inundated the plant and left it submerged for weeks. Staff in the facility was rescued by helicopter several days later.
Despite more than $70 million in sustained damages to the plant and despite being submerged for weeks, primary clarification was restored within six weeks of Katrina and secondary treatment was restored four weeks later.
Muckerheide: What new technologies are being considered for the future?
Becker: The Sewerage & Water Board is completing the design for a sludge dryer to replace our multi-hearth incinerator, which has been broken since Katrina. This project will reduce fuel oil expenses, produce a Class A biosolid, reduce carbon dioxide emissions and increase our solids-processing capacity. This project also has the ability to earn renewable energy credits.
Muckerheide: What can visitors expect when they tour this plant during WEFTEC.12?
Becker: Visitors to the plant are going to see a lot of construction in a very tight area. While the sludge dryer project will begin in early 2013, we have four construction projects that are active at the plant. After [restoring] plant operations since Katrina, we now are spending another $60 million in construction projects that will provide further restoration and enhancements. FEMA [Federal Emergency Management Agency] has committed over $100 million for the projects that have been completed or currently are in construction or design.