May 30, 2008

Older buildings make excavations in New York City risky

City inspection teams shut down many projects

New York

The crack in the facade of the century-old apartment building looked ominous. Nearly an inch wide and jagged, it ran through the basement and up the front wall, causing the building to list precariously to the right.

The damage, city officials said, was caused by construction next door, at 325 20th Street in south Park Slope, Brooklyn, where workers had been digging a hole to lay the foundation for a new apartment building.

Inspectors from the Department of Buildings had been there before, and on March 18 had ordered all work stopped and bracing installed to shore up the neighboring building.

But when they returned last week, they found that while some of the bracing had been installed, not all of their instructions had been followed, and construction was continuing despite the stop-work order.

The damage to the neighboring building was only one of a multitude of problems they had found on the site and, while more troublesome than most, the project illustrated some of the challenges facing the Buildings Department, according to a report in the New York Times.

There are nearly one million buildings in New York City, and more than 4,200 currently under construction, and it falls on the department to monitor them all.

When Mayor Michael Bloomberg took office in 2002, he promised to reform the agency, a 116-year-old institution that had been plagued by corruption and accused of incompetence. Despite some progress, a recent spate of fatal construction accidents, most prominently a crane collapse in March that killed seven, led to the resignation of the buildings commissioner, Patricia J. Lancaster, last month.

While it would be impossible to plant an inspector at every work site every day, even before the crane accident the department recognized that it needed to be more aggressive. The Bloomberg administration recently said that it would hire 63 more inspectors, bringing the total to 461. The department has already established seven enforcement teams, which can appear on job sites unannounced with the authority to suspend work on the spot.

The excavation team, which was formed nine months ago, has conducted 2,772 inspections on 1,685 sites, forcing half of those with active excavation to stop work at least temporarily.

Conditions at some 300 sites were found to be so egregious that a full engineering audit was ordered. Only two passed, said Timothy D. Lynch, chief engineer of the excavations team.

Many of the problems his team found had to do with the unique nature of building in New York, a city with virtually no undeveloped space but constant demand for more.

For instance, in neighborhoods dominated by row houses, many built between 1860 and 1920, homes were often built with little, if any, lateral support, and they rely on abutting structures for stability. Many projects in Brooklyn involve work on rather small lots, requiring an added emphasis on ensuring that neighboring buildings do not shift during excavation.

And most properties feature extensions, often with no foundation at all. Speaking to construction managers at Bovis Lend Lease, one of the city’s largest construction firms, during a recent seminar, Mr. Lynch showed a photo of a building collapse in which a garage came tumbling down, adding that in building inspector parlance, unsecured structures are known as widow makers.

In many Manhattan projects, like larger developments under way in SoHo, the adjacent properties tend to be tenements built from the 1850s to the early 1900s, where hundreds of tons of material can rest on relatively tiny foundations.

Lynch said the design concept for these buildings was simply trial and error.

“They built them by the thousands until they stopped falling down,” he said to the assembled construction managers. “You don’t own them, but you have to maintain them.”

There has been a steady erosion in construction expertise over the last three decades in New York, Lynch told the Bovis managers, particularly as it relates to excavation.

That reality was underscored in March, when a construction worker digging in East New York, Brooklyn, was killed when a wall from the building next door collapsed on him.

“It is not our intent to shut everyone down,” he said sternly. “But we have to keep the site safe.”

Another site in south Park Slope, at 272 21st Street, had been visited by the excavation team recently. One contractor said that he had worked hard to avoid any problems but had already been shut down once for failing to provide sufficient plans for assuring the stability of one neighboring building through a process known as underpinning.

Whenever a foundation is dug deeper than an adjacent foundation, underpinning becomes essential.

But the contractor, Andrew Giancola, 38, had not anticipated that the foundation for the building next to his lot had been poured unevenly, making it a challenge to estimate its depth and thickness.

After he resubmitted his plan and began work again last week, the city’s excavation team showed up unannounced and was still not satisfied that his plans were in accord with the reality of the site.

“This guy is killing us here,” Giancola said as inspectors in blue helmets roamed the site. “I can’t afford to get shut down here.”

For contractors like Giancola, the stakes are high. Every day with no work is thousands of dollars lost. Because of the time he was already forced to suspend work, he said, the bank was considering withdrawing his loan.

Giancola said he understood the city’s determination to improve safety, but he thought that there was not enough clarity on the standards.

In the end, the inspectors let Giancola continue work, but told him to resubmit plans ensuring the stability of the adjacent building.

Robert D’Alessio, director of the excavations team, said he appreciated Giancola’s predicament and emphasized that it was not the department’s intention to stop construction. But he said many of the builders in New York were only now beginning to realize the consequences of more stringent inspections.

“A lot of the existing standards simply weren’t being enforced,” D’Alessio said.

Like others in the construction trade, Giancola said he suspected that inspectors became quicker to stop work after the crane accident. Department officials said that since the various special enforcement units started to operate last year, there had been an increase in violations, but there had not been enough time since the crane accident to make any valid statistical comparisons.

The department came under intense criticism after that accident, and an inspector was charged for having fabricated a report that said he had visited the site 11 days before the accident.

Although the department is generally seen as having made strides in battling corruption, construction projects remain fertile ground for bribery. Four contractors were arrested in January on charges that they had offered bribes to an investigator posing as a buildings official.

DCN News Services

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