Pennsylvania’s natural gas utilities say replacing cast iron and uncoated steel lines in their distribution systems that carry gas to homes and businesses will take decades and cost billions of dollars, a newspaper reported.
The Pittsburgh Tribune-Review cites documents filed with the state Public Utility Commission, which relies on utilities to monitor lines for links.
“The utilities, for some time, they forgot about these pipes. They thought they’d last forever,” said Mohammad Najafi, an engineer and director of the Center for Underground Infrastructure Research at the University of Texas at Austin.
The paper said its analysis of data from the Pipeline and Hazardous Materials Safety Administration in the U.S. Department of Transportation indicates that accidents involving the country’s natural gas distribution pipelines have killed more than 120 people and caused more than $775 million damage in the past decade. Among the accidents along those pipelines – which shouldn’t be confused with larger, higher-pressure interstate transmission lines – is the 2011 Allentown blast that killed five people.
Najafi said engineers expected the cast iron and bare steel pipes in their distribution systems to last about 50 years, but more than one in five miles of Pennsylvania’s gas distribution pipe is older than that. Federal data indicates that Philadelphia residents are served by more than 250 miles of gas mains laid in the 1800s, the paper said.
Most utilities accelerated pipeline replacement programs after the 2012 state law allowed them to increase customers’ bills by as much as 5 percent until they recover the cost. Columbia Gas of Pennsylvania, which serves western Pennsylvania, expects to wrap up its line replacement in 2029, earlier than other utilities, and like the rest of the industry uses protected steel for high-pressure pipes but plastic for most line replacement.
“It has more strength and flexibility. It’s generally immune to the stress of ground movement. It’s cheaper to buy and less costly to install,” company spokeswoman Brynnly Schwartz said.
Cast iron and bare steel account for 95 percent of gas leaks although making up only 6 percent of U.S. transmission lines, according to the public utility commission. A UGI Utilities worker flagged the cast iron pipe involved in the Allentown blast for replacement in 1979, according to a commission filing.
But Philadelphia Gas Works spokesman Barry O’Sullivan said it is possible for a cast iron main to last 150 years or more if properly installed and not in an area with surrounding pressure.
“The reality is for a lot of the cast iron main we have here, there’s nothing inherently wrong with that material,” he said.
The state employs 12 gas safety inspectors, including one supervisor, who oversee a distribution network with nearly 48,000 miles of gas mains. The federal safety administration employs 135 inspectors who oversee nearly 1.3 million miles of gas distribution mains and 320,000 miles of interstate transmission and gathering lines, liquefied natural gas plants and hazardous liquid tanks.
Public utility commission spokeswoman Jennifer Kocher said officials have confidence in what their inspectors are able to do.
“In an ideal world, would we like to have many more blanketing the state? Absolutely, but it’s a balance … of safety versus cost,” she said.
The commission collected $3.1 million in penalties from gas companies for safety violations in Pennsylvania from 2004 through 2013, the third-highest total in the nation behind California and Virginia. State law limited the maximum fine against a natural gas utility to $500,000 until the limit was increased to $2 million in 2012 after the Allentown explosion.
Was this article valuable?
Here are more articles you may enjoy.