Aging pipes, deadly hazards
Last in a four-part series.
Sean Sellers was standing outside his Tacony home in January, a strong smell of natural gas in the air, pointing out the bubbles escaping through cracks in the street to a utility worker.
"Then I saw a bright-orange flash and, a split-second later, boom," he said. The explosion knocked him on his back, which was lucky: "There were bricks flying past my head."
The blast, caused by a leak in a 68-year-old cast-iron pipeline, killed Mark Keeley, 19, a Philadelphia Gas Works employee sent next door to try to fix the leak, and put six others in the hospital.
The explosion leveled an adjacent chiropractic office, broke windows for two blocks around, and tore the front wall off Sellers' home. "It looked like a geyser," he said, "a geyser of fire."
Despite a long history of accidents, and a stack of warnings from safety investigators, there are still thousands of miles of antiquated, leak-prone, cast-iron pipelines running under the streets of Pennsylvania cities and towns. Some are more than 100 years old.
Just three weeks after the Tacony blast, another massive gas explosion, in Allentown, destroyed eight homes and killed five people, including a retired couple and a 4-month-old baby. This one, too, was caused by a leak in an aged cast-iron pipeline, installed in 1928.
When it comes to natural gas pipes, these failing older utility lines pose the greatest safety hazard in Pennsylvania and the rest of the country. Although the dangers have been known for decades, utilities have been moving slowly to replace the lines, and there are no rules requiring them to move faster.
Video of the Tacony Explosion
Reports by consultants for PGW that looked at the issue of PGW's aging pipeline:
Last week, state utility regulators charged PGW with a number of safety violations regarding the Tacony accident, near the intersection of Torresdale Avenue and Disston Street. One violation was for a broken valve that went unrepaired for five months.
For PGW, owned by the City of Philadelphia, more than half of its 3,000 miles of gas mains are still made of cast iron, the highest percentage of any utility in the country. The city also ranks first in the share of pipeline installed before 1960.
At the current replacement rate, about 18 miles a year, it will take PGW 85 years to get rid of all the cast iron. "If we had our druthers, we'd replace all the pipe tomorrow," said Randall Gyory, PGW's senior vice president for operations.
But that's not practical, he said. The cost would be about $1.6 billion. As it is, Gyory said, replacing iron pipes eats up 60 percent of PGW's capital budget every year.
In the meantime, these pipes keep leaking. A look beneath the surface of Philadelphia's streets reveals a PGW system where potentially fatal hazards are commonplace, and utility workers have to race to keep them in check:
Philadelphia has more than 2,000 leaks in its gas mains every year - most of them during cold weather, when frost causes the ground to buckle and the pipes to bend. During 2009, leaks spiked to more than 2,600.
By far, the most dangerous leaks happen when the old mains actually rupture, as happened in the Tacony accident in January. Each year, the city averages more than 300 such main breaks.
Philadelphia has some of the oldest gas pipes still in service in America. Nearly a quarter of them were put in the ground before 1920 - and 10 percent date from the 1800s.
More than 1,100 blocks in Philadelphia are served by gas mains that have broken three or more times, according to one 2007 report. At that time, there were still 57 blocks where the mains had broken five or more times.
The utility declined to reveal the locations of these leakiest pipes, citing the need to protect the system from terrorists.
Still, a map in a 2008 consulting study showed so-called hot zones of leak-prone gas mains scattered throughout the city's neighborhoods, including Fairmount, East Oak Lane, Kensington, and Kingsessing.
This block-by-block tracking system - used by PGW to prioritize its pipe replacements - doesn't always prevent accidents. There had never been a pipeline break in that block of Disston Street before the January accident, PGW said.
Meanwhile, the Pennsylvania Public Utility Commission, in its safety complaint on the Tacony accident, said the utility had not been recording enough details on the condition of its pipes - including how badly they were corroded.
As is the case with pipelines across the country, most of the responsibility for checking the safety of these old, failing, cast-iron pipes falls to the utilities themselves. Government safety checks are mostly handled by thinly staffed groups of state agencies; Pennsylvania has just eight PUC inspectors to cover the whole state.
And the federal safety agency - the Pipeline and Hazardous Materials Safety Administration, a small office within the Department of Transportation - was criticized this fall for its weak oversight of state safety programs.
Promising to do better, the federal agency last week began a series of utility safety audits - beginning in Pennsylvania. The agency's first stop was UGI Utilities Inc. in Allentown.
"We need some more regulation," said Allentown Mayor Ed Pawlowski, who after the accident became a national voice for tougher rules. "And if the state isn't going to do it, I'm going to keep fighting at the federal level to put regulations in place. Because I'm scared."