Massachusetts gas customers have spent millions each year on a state program incentivizing utilities to replace old, leaky pipes in the name of safety and reducing greenhouse gas emissions.
But with energy bills skyrocketing, state legislators are considering scaling back or outright eliminating the program, which the Senate estimates could save consumers more than a billion dollars on their gas bills.
Now, a new study gives opponents of the program further ammunition. A report from The Future of Heat Initiative, a nonprofit funded by climate-focused foundations, has found that increased spending on pipe replacement has not measurably improved safety.
Indeed, the report concludes, states like Massachusetts that have aggressively pursued these projects have had more incidents than those that didn’t, suggesting that digging up old pipes is itself a source of risk.
“You can feel confident in reducing the level of spending on pipe replacement programs without compromising the safety of the system,” said Jamie Van Nostrand, the nonprofit’s policy director and former chair of the Massachusetts Department of Public Utilities.
The gas industry disputed the findings, arguing that pipeline replacement efforts have protected customers, and the failures those efforts have prevented from occurring cannot be measured.
The report comes at a critical moment for the future of the Gas System Enhancement Program, or GSEP. Lawmakers created the program in 2014 to improve public safety and reduce planet-warming emissions from leaks. Yet even as spending has ballooned to roughly $800 million in 2024, paid for by customers’ monthly bills, opponents say it has not delivered on its promised benefits.
Now, state lawmakers are negotiating a sweeping energy bill that could determine the fate of the program. The Senate has sought to phase out GSEP, a move that Senator Michael Barrett said could save customers as much as $1.46 billion over the next 10 years.
“We’ve paid too much, but at least we wanted to believe that we were safer,” Barrett said. “Now it turns out that we’ve paid too much, and we did not make our people any safer than they would have been.”
Brendan Moss, a spokesperson for National Grid, said the Senate’s proposal would limit essential investments while failing to deliver meaningful affordability improvements for customers.
“The need to replace aging, leak-prone infrastructure will not disappear in 2030,” he said. “Deferring that work is not an affordability strategy because it shifts costs into the future while increasing risks to the system customers rely on today.”
Olessa Stepanova, a spokesperson for Eversource, said in a statement that the older pipe is deteriorating faster than the transition to electrification can advance.
“Critically,” she said, “once the pace of replacement falls behind the rate of deterioration, it is difficult to catch up, and this can result in significantly increased risk to public safety, as well as higher operations and maintenance costs” because of repeated repairs and emergency work.
The Future of Heat Initiative, which conducted and paid for the study, describes itself as a nonpartisan organization that supports energy regulators. It declined to list all its funders, although it said the Climate Imperative Foundation and the Heising-Simons Foundation, which support clean energy, were among them.
The report examined federal gas incident data before and after 2011, when the federal government implemented policies intended to improve the safety of gas systems. Though spending on pipeline replacement surged, the report found it was not matched by a statistically significant improvement in safety outcomes. There has been a long-running national decline in gas incidents, but there was no change in the slope of that trend, according to the report.
Furthermore, the report concluded that the states that invested most heavily in pipe replacement after 2011 saw higher rates of significant incidents — including those that caused fatalities or in-patient hospitalizations — than the other states.
Michael Bloomberg, the executive director of The Future of Heat Initiative, said an important reason for the increase appears to be excavation damage, a leading cause of incidents on gas mains.
“When you’re doing a lot of digging, that itself comes with risk,” he said.
In Massachusetts, there were 24 injuries and three fatalities related to gas distribution incidents reported to the federal government between 2001 and 2013. In the more than 12 years since the program’s inception, there were 29 injuries and two fatalities reported.
Most of those resulted from a GSEP project undertaken by Columbia Gas. In 2018, workers replacing gas pipes in the Merrimack Valley abandoned an old main without removing its pressure sensors, sending high-pressure gas surging through a system that wasn’t built to handle it. Fires and explosions rocked the region, killing one person and sending roughly two dozen to local hospitals.
Nathan Phillips, a Boston University researcher who has studied gas leaks, said the report was the most comprehensive look to date of the safety impacts of pipeline replacements.
“We do know that third-party damage and excavation is the leading cause of pipeline incidents,” he said. “When you’re messing with these pipes in any way, shape, or form, you’re contributing to that probability of risk.”
Rob Jackson, an environmental scientist at Stanford who has studied pipe replacement programs, said the study adds to the body of evidence that progress has been slow and “not resulted in much benefit for all of the money spent.”
However, he cautioned against concluding that these programs are making the systems less safe in the long term. He said digging more holes increases the chance of mistakes, but cities that have completed these repairs have seen a decrease in incidents after the work is finished.
The American Gas Association, a trade group, contested the notion that the effectiveness of pipe replacement projects could be assessed based on the data. The report’s method does not reflect the incidents that never occur and cannot be measured, the association said.
In addition to reducing the risk of accidents, the association said, pipe replacements bring other benefits, including reducing methane emissions.
The state’s two biggest utilities — National Grid and Eversource — said GSEP has a proven track record of improving safety.
Stepanova, the spokesperson for Eversource, said conclusions about GSEP should not be drawn from the national report, given that Massachusetts has one of the oldest natural gas systems in the United States.
After the Merrimack Valley explosions, Eversource went on to purchase Columbia Gas’s natural gas assets in Massachusetts. Stepanova said the accident could have occurred with any type of work on the natural gas system with the deficiencies by Columbia Gas that were identified.
“Blending the Merrimack Valley tragedy with GSEP draws the wrong safety conclusion,” she said.
Kate Selig can be reached at kate.selig@globe.com. Follow her on X @kate_selig.