Decrepit Water Main Could Blow Anytime Right Under Fifth

Every day, tens of thousands of New Yorkers walk and ride above a 48-inch-wide Victorian-era water main that runs beneath the west side of Fifth Avenue, oblivious to the fact that this big cast-iron pipe under their feet is a brittle relic that has exploded in spectacular fashion three times in the last 11 years. Most recently, in 1998, a major rupture sent several hundred thousand gallons of water cascading through the streets in the area near 19th Street, creating a curb-to-curb sink hole that swallowed up street signs, parking meters and a 1984 Buick Riviera. When the torrent finally subsided, a gas line cracked and shot a plume of flame two stories into the air.

So why doesn’t the city just bite the bullet and replace the long-suffering pipe? Well, it can’t. New Yorkers require 1.2 billion gallons of water a day to slake their prodigious thirst, and the city doesn’t have the capacity to take the Fifth Avenue main out of service for any length of time. This is because it’s not just any old pipe: Laid primarily in 1870 and 1897, the big Fifth Avenue main is a spine running down the center of Manhattan that carries water from the Croton and Catskill systems to the lower part of the island.

Still, the city can’t just wait around for the next geyser of water and fire to erupt from the bowels of Fifth Avenue. Which is why city officials are looking into the option of resuscitating a now-defunct, one-and-a-half-mile section of the Madison Avenue water main that runs from 68th Street down to the 30′s.

This would provide enough added flow to allow the Fifth Avenue main to go on the disabled list and undergo rehabilitation, which in turn would allow the people who keep an eye on the city’s 2,168 miles of notoriously brittle unlined, cast-iron water mains to sleep easier.

Puzzling out how the Madison main can be revived, without plunging the avenue into a monstrous, protracted traffic jam is the current preoccupation of Doug Greeley, a deputy commissioner with the city’s Department of Environmental Protection and the man responsible for safeguarding New York’s sprawling water system.

“We had a water-main break on Madison in 1984, and we couldn’t locate the break, so we shut it down and left it,” said Mr. Greeley. “We’ve compensated for the loss of that pipe …. But if you want to go back and do something with the Fifth Avenue main, you won’t be able to, because there’s not enough capacity.”

Mr. Greeley wants the city to make the leap forward to what are called “trenchless technologies”–so called because they allow workers to recondition existing pipes without digging long, hugely disruptive ditches. He wants to insert a new lining inside the 48-inch Madison Avenue pipe, which was laid in 1870 and 1871 and is even more decrepit than its Fifth Avenue neighbor. The trenchless methods that Mr. Greeley champions, which are popular abroad from London to Tokyo, do require the digging of access pits, but they are dramatically less disruptive to life on the surface. The Madison Avenue project, if it indeed goes forward, will provide the first test of the city’s ability–and will–to use such nondisruptive techniques on the large cast-iron mains that most need attention. Mayor Rudolph Giuliani’s office did not return calls for comment.

The decision to pursue a trenchless lining of the Madison main was driven in part by trepidation among city officials about excavating major East Side thoroughfares the old-fashioned way.

“The concern among city officials was that they had this major aqueduct in Manhattan which was in very poor condition, and to rehabilitate it traditionally was going to be very costly and disruptive,” said James Thomson, an international consulting engineer who has met with city officials about the proposed lining of Madison Avenue. “The disruption was likely to be of a level which would cause public outcry and involvement of the politicians.”

The first stage in the trenchless plan, according to Richard Ocken, deputy commissioner for infrastructure at the city’s Department of Design and Construction, is to put out a contract to clean the Madison Avenue main from 40th to 79th streets, test the remaining strength of its iron and send a man through the pipe to see how straight it runs.

“This pipe dates from the Civil War era,” said Mr. Ocken. “You would think something that old would be straight–what else was in the ground back then?–but we need to confirm that. If the pipe bends in certain places, there may be sections you can’t line. We’ve never done this before, so we’re looking at the condition and geometry of the pipe to see if we can go forward.”

The contract for the project, which includes a currently active section of pipe north of 68th Street, will be bid this summer at the earliest, said Matthew Monahan, a D.D.C. spokesman. If the D.D.C. ultimately concludes that lining the Madison Avenue main is not feasible, the D.E.P. would make the call on whether it would then be necessary to dig up and replace the Madison main through an open-cut trench, according to Mr. Monahan. “D.E.P. would have to determine if we would have to go ahead with an open-street excavation, or if there is ample redundancy in the system,” he said.

“We don’t see why Madison could not be lined,” said Geoff Ryan, a spokesman for the D.E.P. “If it can’t be lined–and we don’t see why it can’t be–we can get by on the Fifth Avenue main. But we’d rather not.

“I don’t even want to speculate on digging up Madison Avenue,” Mr. Ryan added. “It’s not something we’re eager to look at.”

Meet the Aqualogs

In the meantime, the Fifth Avenue main remains something of a time bomb, so Mr. Greeley has turned to another emerging technology to try to prevent a repeat of 1998′s Buick-swallowing blowout. In many cases, such water-main ruptures are preceded by a leak, which can wash away the soil beneath a pipe until its weight is unsupported and it blows out under stress.

In the wake of the 1998 disaster, therefore, Mr. Greeley set out to spot leaks early by deploying a corps of 60 subterranean electronic snoops to eavesdrop on problematic water mains. Called Aqualogs, the orange-tipped cylindrical devices, which resemble oversize lipsticks, are attached to water mains, through manholes, during daytime hours. At 2 a.m. the Aqualogs click on, taking samples of noise every 30 seconds until 4 a.m., when they click off again. During this time, the Aqualogs monitor mechanical vibrations, trying to pick up the telltale sound of water escaping from a pipe.

The devices are exquisitely sensitive. “I have heard high heels on sidewalks,” said Mr. Greeley. “I have heard people singing in their showers, I have heard jackhammers, people in their basements, bus horns, taxis–you name it.”

Thus far, Mr. Greeley’s underground network of spies has turned up four leaks on the troubled Fifth Avenue main. In three cases, the city dug up the street and recaulked the leaky joints; in the fourth, a customer’s leaking water line was in contact with the main, and he was prevailed upon to repair it. Had the leaks gone undetected, Mr. Greeley said, any one of them might have developed into “one of those big intersection-eaters.”

But the system is labor-intensive. The Aqualogs must be pulled out of their manholes every 10 days and their data downloaded so it can be analyzed by a computer back in Queens. Con Ed is helping the D.E.P. develop the ability to use Con Ed power lines, which are often situated cheek-by-jowl with the water pipes, to carry messages from the Aqualogs up to Mr. Greeley’s people 24 hours a day.

Nevertheless, this stomach-churning game is ultimately unwinnable. Sooner or later, Mr. Greeley acknowledged, the world-weary main on Fifth must either be replaced or rehabilitated.

“My instinct would have been, until very recently, to replace them,” Mr. Greeley said of the Fifth and Madison Avenue mains. “Now I say reline them, recondition them. What I want is a smooth interior of the pipe that’s not going to break and not going to accumulate tuburculation”–wart-like rust buildups that are common inside cast-iron pipes. “I want it to withstand loads so it doesn’t break or leak. I want good valves on it so I can control it. And if you can achieve all these things, why not line it?”

Industry experts say Mr. Greeley’s vision is no pipe dream. “Most of the time, if you look hard enough, you can find sound and economical trenchless solutions,” said Robert Zlokovitz, a former Con Ed research and development manager who is leading a city-funded study of the techniques for Brooklyn’s Urban Utility Center. But the four-foot Madison main could prove tricky.

“There are a lot of trenchless technologies, but very few for the big 48-inch pipes,” said Mr. Zlokovitz. “You see all sorts of pretty brochures, but when you ask the vendor ‘Can you do it for a 48-inch main?’, the answer is no.”

Mr. Zlokovitz believes three techniques could work in New York, however, including the patented “Subline” method, which recently proved successful on a 48-inch pipe in Holland. In a process reminiscent of the way that curb-side Christmas-tree salesmen shrink your Douglas fir by shoving it through a metal tube, the “Subline” technique involves taking a polyethylene liner and feeding it through a machine that reduces its diameter by about 40 percent. The liner is then winched through the underground pipe before being restored to its original shape and size by water pressure.

“That Subline liner in Holland was purpose-built for a 48-inch main, and it’s exactly what we would need in New York,” said Mr. Zlokovitz.

Such trenchless triumphs are the sort of thing that fire Mr. Greeley’s imagination. Sitting recently in his Queens office, with its view of the traffic snarl on the Long Island Expressway, the D.E.P. official unfurled a linen scroll. It was a map of the city’s byzantine water-main network, a maze of orange and blue and pink lines, each color denoting a different pressure level. Running his slender index finger down the middle of Manhattan, Mr. Greeley spoke of the positive effects of reviving the defunct stretch of the Madison main. “If you could recondition that section of main and could put it back in service,” he said, “and, thinking down the road, if you got the 36-inch main on the east side of Fifth Avenue back in service, then you could take that 48-inch main on the west side of Fifth Avenue out of service and recondition it.”

But that’s only the beginning. Beneath New York’s streets run 163 miles of pipe laid in the 1890′s, 65 miles from the 1880′s, 175 miles from the 1870′s, and 28 miles from before that. Mr. Greeley moved his fingertip down Fifth Avenue and into the Village. “This main in West 10th Street dates to 1844,” he said with admiration. “It never broke. But it’s going to be a very good candidate for relining because it’s rusty. That would be a beaut!”