By Beth Treffeisen
Underneath the battered Boston streets, miles of gas lines, some more than 100 years old, are spewing out natural gas and causing consequences that often go unnoticed.
“One thing is to highlight it to make the indivisible, visible,” said Steven Hamburg, the chief scientist at the Environmental Defense Fund.
With more than 1,000 active gas leaks ranging in size across Boston, outraged advocacy groups, residents, and ratepayers are speaking out against utility companies. Those groups allege the utilities have left the non-hazardous leaks open for years, killing nearby vegetation, triggering long-term respiratory illnesses, and adding harmful chemicals into the atmosphere that aid global warming.
There have been some gas leaks left unfixed for decades, including one in Fenway that has been left for over 30 years. About 45 percent of the pipes in Boston are made from cast iron or other corrosive and leak-prone materials.
“This is rampant – it’s all over the place,” said Robert Ackley from Gas Safety Inc.. “Thousands and thousands of gas leaks run through Boston.”
Conservative estimates say there are around 1,300 gas leaks in Boston, but in a 2013 Boston University study that mapped the location and volume of the gas leaks in the city, it estimated the leaks to be closer to 3,000.
In downtown Boston alone, with high concentrations in the Back Bay, Home Energy Efficiency Team (HEET) reported 246 un-repaired leaks as of February 2015. HEET also found that 30 percent of the leaks where missing from 2015 data.
“Being in the city of Boston, there are old cast iron pipes that are a century in age,” said Nathan Phillips, the professor at BU who spearheaded the mapping study. “And a big percentage of those are in the Back Bay.”
The consequences of the gas leaks, he said, start at the local level – at the point of the leak where escaping methane causes asphyxia in the roots of nearby trees, blocking essential oxygen the tree needs to survive.
He said on a regional level gas leaks degrade air quality and can cause asthma problems. On a global scale, natural gas that is made up of mostly methane, a potent greenhouse gas, makes it a big contributor to global warming.
“It is a more serious greenhouse gas,” said Matthew Schreiner, the co-founder and team leader at HEET. “In Massachusetts it is equal to all the carbon emissions of automobiles. It is more nasty than carbon dioxide.”
The highest volume leaks that are referred to as “super-emitters” are statistical outliers that in any large population of leaks emit by the far the most, according to the Sierra Club of Massachusetts. According to the BU study it found that seven percent of gas leaks are emitting 50 percent of the leaked gas. Even though they are emitting high volumes of gas, the air to gas ratio at these sites did not qualify them to be deemed unsafe.
According Danielle Williamson, the spokeswoman for National Grid, to be considered a hazardous a gas leak the air to gas ratio has to be between five to 15 percent.
“You have what is considered a significant amount of gas, but in no ways pass as hazardous,” said Williamson referring to “super-emitters.” The challenge she said is looking at the gas leaks for volume, which is an entirely different perspective than safety.
“Only in the last year has it politically transitioned to it including methane emissions and the environment as well,” said Williamson.
Recently the state passed a bill that makes it so there is more transparency in reporting the gas leaks from the utilities and requires them to better coordinate fixing pipes with road construction projects, such as with water and sewer pipes and electrical lines that run underground.
The City Council is also hoping to pass an ordinance to fix the leaks within a six-year process, according to City Councilor Matt O’Malley, who has been working on the issue about a year and half.
In mid-July, he co-chaired the Committee on Government Operations hearing that included testimonies on the impacts of gas leaks in Boston as well as representatives from National Grid and Eversource.
In the ordinance, O’Malley hopes to get better coordination between the city with Boston Water & Sewer, FiOS construction of fiber optic lines and the utility companies to limit the amount of time of open roads during construction.
“Not only is it an environmental problem and a public health problem, but it is affecting the rate payers,” said O’Malley.
It is estimated that $90 million per year is being spent on gas that has leaked out, he said. Ratepayers are responsible for not only the gas that has leaked into the atmosphere, but also for fixing the leaks managed by National Grid and Eversource.
To fix a mile of pipes, it can cost anywhere between $1.5 million to $2.5 million depending on the significance of the leak and by the location, according to National Grid. To fix a smaller leak, it can go into the thousands of dollars.
“It’s like putting a Band-Aid on,” said Williamson, who said sometimes when they fix smaller leaks the construction could cause gas leaks to migrate through the system.
There are three grades of gas leaks. ‘Ones’ are the biggest, are potentially dangerous, and need to be responded to immediately, a ‘two’ is a non-hazardous leak but has to be maintained every six months and repaired in one year, and a ‘three’ is non-hazardous and needs to be checked on annually.
According to National Grid there are currently no regulatory requirements to repair grade three leaks.
Cast and wrought iron pipes are one of the oldest energy pipelines constructed in the United States that still deliver natural gas today. The degrading nature of iron alloys, the age of the pipelines, and the pipe joints design have increased the risk of their use.
National Grid has been replacing these pipes with plastic to reduce the amounts of leaks that often occur in the cast and wrought iron pipes that have a joints that are prone to leaking about every 12 feet.
Phillips said in order to see if there is a gas leak, one can look around for dead vegetation, tree decay and dead grass. As well, methane that is odorless but has the addition of mercaptan to give it a sulfur smell is another good indicator.
“It is a little intermittent because it depends on where the wind is going,” said Phillips, adding that the grass can even absorb the smell.
With the push to fix the gas leaks faster, construction sites may soon begin popping up around the city.
“We are certainly going to see an increase in construction,” said Hamburg. “It’s good and it’s bad – it’s disruptive.”