Sixty-three percent of New Orleans water lost to leaks
June 09, 2006
By Michelle Krupa
Near the corner of Frenchmen Street and St. Claude Avenue, a half-mile from the Mississippi River and more than four miles south of Lake Pontchartrain, Gregory App can hear the gushing.
Since at least February, App has been able to lounge in his front room and listen to water flowing beneath the floorboards of his raised 1845 cottage. Peering out the window, he can keep tabs on the growth of a 5-foot-deep cavity that has slowly enveloped his street.
"I literally have a sinkhole in front of my house," said App, a real estate investor who said he has called the New Orleans Sewerage & Water Board four times to request repairs, to no avail. "Finally, I bought a piece of plywood to put down over the 5-foot hole under my brick sidewalk.
"I could take a chlorinated bath underneath that piece of plywood on my sidewalk," he said.
Nine months after Hurricane Katrina, S&WB officials are scrambling to plug an untold number of underground leaks, cracks and gashes, most of which sprung when the epic storm's winds uprooted trees and pried loose the water pipes around them.
Even after the water board plugged a 15 million-gallon-per-day break this week in a main water pipe in Bywater, an estimated 85 million gallons of drinking water still are flowing every day into the easily eroded southeast Louisiana soil.
Local experts say the seepage not only leads to low water pressure but also threatens city streets, sewerage lines and potentially the structural stability of houses.
To try to get a grip on the problem, S&WB officials have hired a contractor to install 400 sensors along 80 miles of water pipes beneath the city. The detectors are designed to sense vibrations and pinpoint leaks hidden beneath the pavement.
But the water board, already facing an apparent backlog of complaints, still will have to make repairs. And because of fiscal constraints, the contract initially will cover only 5 percent of the 1,600 miles of water pipes that snake through subterranean New Orleans.
Meanwhile, officials in Jefferson and St. Tammany parishes say their water systems are back to pre-Katrina status, or that no significant problems persist. Even in St. Bernard, which flooded border-to-border during Katrina, only about 10 percent of drinking water is escaping from the system, compared with at least 63 percent in New Orleans.
The potential problems associated with a leaky water system are many. Foremost is the condition of roadways, which are prone to sink into ground made mushy by seeping water.
"The physical condition of the streets is really destroyed because of the water leak," said Enrique LaMotta, a professor of environmental and civil engineering at the University of New Orleans. "There is really not a good foundation once the soil is washed away by the water."
Leaky water pipes also could lead to a ruined sewer system, LaMotta said, noting that sewer pipes could bend or crack under the weight of wet soil or because of its instability.
"If the sewer system sinks, we could have wastewater leaking out of the sewer pipes," he said.
Denise Reed, a professor of earth and environmental science at UNO, said moistening the city's soil, if done consistently and in moderation, actually may be beneficial during an arid period.
"The reason we have such subsidence is because the soils are dry," she said, adding that exceptionally dry soil could bring about pipe fissures. "If the Sewerage & Water Board were able to irrigate the subsurface in an equal fashion, some might say that's a good thing."
However, she stressed that large breaks that shoot powerful streams of water into the subsurface, especially the irregular ground beneath New Orleans' streets, certainly imperils infrastructure.
"Trying to maintain some kind of rigid pipe system while everything is subsiding is a very, very difficult task," she said.
Considering the additional damage wrought by Katrina, Reed said that perhaps the city's only saving grace is its proximity to a reliable water source.
"We're lucky in Louisiana in that we have a lot of fresh water," she said. "The Mississippi River provides us as much fresh water as we could want. If we were out in the West, could you imagine what this waste of water would be worth?"
A losing proposition
Water board officials have not revealed how much money they lose every day from the millions of gallons of water escaping through the busted underground pipes, though they said this week that seepage has always been a problem for the city's aged water system.
Before the Aug. 29 storm, New Orleans' 455,000 residents used about 120 million gallons of water every day, and about 30 percent of it regularly disappeared through cracked pipes, or was used to fight fires or for other public uses, said S&WB Executive Director Marcia St. Martin.
That means that 84 million gallons served the city's pre-Katrina citizenry.
Now, with the population estimated at 221,000, the S&WB is pumping out even more than before the storm: about 135 million gallons per day, she said. Billing records show that only 50 million gallons are needed for private use, so 85 million gallons are pouring into the ground.
Since Katrina, water board crews have patched 17,000 leaks in the drinking water system, St. Martin said. But because officials don't know exactly where to find the remaining breaks, they have hired Fluid Conservation Systems Inc. of Ohio to help with reconnaissance.
Under a six-month pilot program, the S&WB will pay $192,500, most of it to buy 400 "permalog" devices that will be installed by contractors every two or three blocks in one section of town, said Tom McGee, the company's director of operations. The location has not yet been set.
Listening for leaks
Roughly the size of a soda can, the battery-operated units are attached with magnets to water pipes near shutoff valves. They have radio transmitters and are programmed to turn on every day at 2 a.m., when they go to work "listening" for leaks.
"The water spring makes a noise on the pipe, a vibration, that can be heard from two or three blocks away," McGee said. The process is best done at night, he said, because there's little traffic noise and water use is low, meaning water pressure in the pipes is at its height.
Once readings have been made, contractors drive around the neighborhood where the "loggers" have been planted and receive radio transmissions of the underground data.
"But these devices don't tell you where to dig," McGee said. "They just tell you there's a leak on the block."
To further home in on the problem, Fluid Conservation Systems sends in a two-person crew to attach sound-wave sensors at the end of each block in a section where a leak was detected. Again relying on vibrations, the sensors become "sophisticated stopwatches" that track the amount of time it takes vibrations to reach each end of the block, McGee said.
Judging by the length of the pipe, workers can pinpoint the leak's location.
"The normal average in a city the age of New Orleans would be to find one leak for every three miles of pipe," McGee said. "We'll probably find about one every mile of pipe, given the stories I've heard about how much water they're losing."
Fluid Conservation Systems expects to begin installing sensors June 19. Until then, and after the process gets under way, water board officials are asking residents to report any leaks, including the sound of water running underground, by calling (504) 52-WATER or through the S&WB Web site, www.swbno.org.
The reporting system, however, is not always user-friendly, some residents have said. Pat Denton said she called three weeks ago to report "a big pool" of water at Camp and Amelia streets Uptown. A pipe had been leaking for at least two months, she said, but even after registering her complaint, the pond still stood Thursday.
"The birds have been really enjoying it, so on the one hand, I really hate to see it go," Denton said. "But it is seeping. It's making everything mushy. You can't really park in front of the house that's right there."
S&WB spokesman Robert Jackson said he did not know whether his agency had a backlog of work orders for water system repairs. But he noted that the board often puts off mending small leaks on public property in lieu of major problems, such as broken hydrants, busted water mains and pipe fissures that leave whole blocks or neighborhoods with no water service.
"We have to ask: Is it a small trickling leak, or (do) you have water pouring out of a hole or you have no water in a whole part of town?" he said.
Jackson also said S&WB employees cannot enter private property without the owner's permission to fix a leak, even if water has flowed onto public ground. And he said some problems that may appear to be water board issues, such as sinkholes, may actually be the responsibility of the city streets or public works departments; those are referred to City Hall.
Though the scope of the water system damage in New Orleans is unclear, officials agree that the rebuilding task is huge. Meanwhile, nearby parishes have managed to resurrect their drinking water pipelines and have had few, if any, major service interruptions since getting back online.
In St. Bernard Parish, drinking water is available as far south as Verret, and in areas where service has been restored, seepage from cracked pipes is only about 10 percent, Chief Administrative Officer David Peralta said.
Though he conceded that leaks likely are more prevalent in lower St. Bernard, Peralta said officials have not considered hiring a contractor to root them out.
"We probably are not facing the problems New Orleans is," he said. "They're just so much bigger than we are. We're just using our normal procedures: word of mouth."
In Jefferson Parish, Water Department Director Randy Shuler said that within three weeks of Katrina, while much of New Orleans still was under water, 30 parish and contractor crews repaired 480 breaks in the water system, the equivalent of an ordinary year's worth of work.
The department fixed about 50 more leaks discovered by residents when they returned home, and soon after that, "everything that was related to the hurricane was fixed," he said.
Shuler noted, however, that he fielded three calls Thursday for broken water pipes, an unusually high number for one day.
"We haven't had a lot of rain lately and the temperatures are getting hot, so you're going to see some soil subsidence, and you're going to see some lines break at the joints," he said, adding that similar problems could begin popping up in New Orleans.
St. Tammany Parish, which has several private and public water systems, has had no significant water-pressure problems. A parish government spokesman said the Engineering Department was unaware of any problems, and municipal systems reported no pressure issues.
"We have had no water pressure problems during the storm, after the storm or now," Mandeville Mayor Eddie Price said. "Our water pressure's as high as it's ever been."
In Slidell, Public Utilities Superintendent Michael Isenberg said Katrina-related water system repairs are complete. "We don't have any problems," he said. "The breaks that we had after the storm, we addressed."