A natural gas expert called the two-month timeline proposed for replacing 48 miles of pipeline in the Merrimack Valley "extremely aggressive."
Mark McDonald, president of NatGas Consulting, said the plan to restore gas service by Nov. 19 to all homes and businesses across the three communities affected by the gas disaster was "unrealistic, wishful thinking."
"Weeks doesn't come into my realm of possibility," McDonald said. "It would take normally one to two years to aggressively replace that level of infrastructure."
Over-pressurization of gas lines on Sept. 13 triggered a series of explosions and fires across Lawrence, Andover and North Andover that killed an 18-year-old, injured several more and destroyed or damaged dozens of homes. The incident forced the shut-off of 8,600 gas meters in the affected area, plus the shutdown of thousands more as a precaution.
Service is being restored quickly to customers in the area that was not affected by the over-pressurization -- but restoring service in the affected zone is expected to take much longer. The pressure is on to restore gas flow, as homes grow colder by the night and businesses continue to lose money by the day.
The gas disaster exposes larger issues with the Merrimack Valley's aging utility infrastructure, an antiquated system that still includes century-old pipes prone to leaks.
Approximately 97 percent of natural gas distribution pipelines in the United States were made of plastic or steel at the end of 2017, while the remaining 3 percent was mostly older iron pipe, according to the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration.
Massachusetts is among four states — including New York, New Jersey and Pennsylvania — that account for half of all cast-iron pipe in the country, according to a 2017 report from the U.S. Department of Energy.
"Massachusetts has the second-oldest leak-prone infrastructure in the nation," said Audrey Schulman of the Home Energy Efficiency Team, which tracks gas leaks and works on energy efficiency projects.
Antiquated systems can lead to several problems, Schulman said. Older pipes leak, leading to increased gas emissions. Those leaks also lead to higher costs for customers, as utility companies account for lost gas in setting rates, she said.
And old pipelines can break, which can lead to "a catastrophic problem," like an explosion. Officials have said the Merrimack Valley gas explosions were likely linked to over-pressurized gas lines, however.
The service life for a cast-iron main is about 100 years, McDonald said, meaning "a lot of this pipe should have been taken out years ago."
"The system is antiquated, it's outdated, it's dangerous," McDonald said, and until recently, "no one required (utility companies) to replace this infrastructure."
There has been a ramp-up over the past decade to replace aging cast-iron pipes, including financial incentives to make the work more feasible. Across the country, regulators have pushed utilities to submit plans outlining expansive replacement of old, leak-prone equipment after a California pipeline explosion killed eight people in 2010.
In a recent Gas System Enhancement Plan filed with the Massachusetts Department of Public Utilities, Columbia Gas of Massachusetts — the company that owns the pipelines implicated in last week's gas disaster — said it planned to spend $80 million in 2018 to replace between 55 and 59 miles of steel and cast-iron pipes, and 4,180 services.
Columbia Gas also estimated it would repair about 150 Level 3 gas leaks this year — those with the least severity, which utility companies are technically not required to repair but must monitor annually — with a budget for that process of $469,050, or roughly $3,000 per leak.
There were 11,902 gas leaks across the state that were repaired in 2017, and 15,829 that were not, according to data from utility filings compiled by HEET. Lawrence had 187 repaired leaks and 106 not-repaired leaks; Andover had 42 repaired leaks and 39 that went without repair; and North Andover had 17 leaks repaired and 27 that were not, according to the data.
These maps from HEET show 2017 gas leaks in Lawrence, Andover and North Andover. Points in red show leaks that have been repaired. Points in yellow indicate not-repaired leaks.
According to a 2014 report by the American Gas Association, it generally costs $1 million to $5 million per mile of replaced pipe. Schulman said cost estimates for replacing the state's leak-prone infrastructure was upward of $9 billion, according to utility filings.
The cost of replacing mains impacted by the Merrimack Valley gas disaster could cost even more than the standard $1 million per mile, due to the "emergency factor," McDonald said, noting that more contractors would need to be hired and crews would likely be in the area around the clock due to the rush nature of the job.
Gov. Charlie Baker said Friday Columbia Gas will pay for the reconstruction, but provided no cost estimate.
Columbia Gas serves roughly 320,000 active customers across the state, with service areas in Lawrence, Brockton, and Springfield. The Lawrence area — which serves Lawrence, Andover, North Andover, Methuen and Haverhill — is the company's smallest service area in terms of geography and customers, according to information filed with the state.
Replacing pipelines in urban areas comes with its own set of challenges. Urban areas like Lawrence are more densely populated, have more traffic and have a higher volume of pipes and meters than more suburban areas like Andover, McDonald said.
"It's not just the main replacement, it's also the connections to each service and each home and that has to be replaced and reconnected, and certainly that's the much more difficult task that the gas companies have struggled with before," he said.
Even with extra help and resources, experts were wary of the timeline. Schulman echoed McDonald in saying it would be "extremely aggressive" to get the emergency repairs done even by Dec. 31.
Is replacement the answer?
Schulman said Columbia Gas had actually been "really on top of" replacing aging pipelines before the Merrimack Valley incident. The average amount of leak-prone infrastructure across utility companies in the state is 27 percent, but Columbia Gas's average was closer to 15 percent, she said. Utility companies each operate their own distribution systems.
"They saw this problem ahead of everyone else and started working on it," she said. "They've done a good job of that."
Columbia Gas, however, has come under fire from the state Department of Public Utilities in recent years, incurring $100,000 in fines for safety violations that included failing to know the location of the main line, failure to produce pressure test records, inadequate gas standards, improper pressure testing, failing to install new service at an adequate depth, and failing to follow its own procedures and federal pipeline safety regulations when using leak repair kits.
The utility company was also deemed responsible for a 2012 natural gas explosion at a strip club in Springfield, which injured 18 people. A company worker investigating an odor of gas accidentally punctured a high-pressure gas line, triggering an explosion, authorities said.
And in 2014, the National Transportation Safety Board faulted a subsidiary of Indiana-based NiSource, the parent company of Columbia Gas, for a pipeline explosion in Sissonville, West Virginia, that destroyed three houses and damaged several others when a corroded portion of pipe ruptured. Investigators determined the pipeline had not been inspected or tested since 1988.
NiSource has since sold the company — Columbia Gas Transmission Corp. — which is now part of Calgary-based energy corporation TransCanada.
Schulman said the Valley explosions and other incidents nationwide call into question whether natural gas should be the country's go-to fuel source.
"Piping an explosive fuel into our homes and lighting it on fire is not necessarily the safest thing to do, and maybe we want to rethink that and move to a more modern system," she said.
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