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Brookline Gas Leaks

Not Safe, Not Clean, Not Green


Smells Like Climate Change

The gas pipes that run beneath our streets are riddled with leaks. At last count, Brookline had 219 active, unrepaired leaks releasing methane gas into our neighborhoods. Methane gas causes air pollution, drives climate change, poses a public safety hazard, and kills trees. Plus, it smells terrible!

Mothers Out Front Brookline is calling on National Grid to fix the largest, most dangerous leaks while we simultaneously transition away from methane gas – a dirty fossil fuel. Join us in advocating for a just transition to clean heat and clean air for Brookline!


Did You Know?

What is “natural” gas?

Methane (CH4), a tasteless, colorless, and odorless gas, is the primary component of natural gas. Gas utility companies add mercaptan, a sulfur-smelling chemical, so people can recognize and report gas leaks when they occur.

How do gas leaks contribute to climate change?

Methane is one of the most potent greenhouse gases. Methane’s lifetime in the atmosphere is much shorter than carbon dioxide (CO2), but methane is more efficient at trapping radiation than CO2. Pound for pound, the comparative impact of methane is 25 times greater than CO2 over a 100-year period.

Why does Massachusetts have so many gas leaks, and what is the impact of them all?

Massachusetts has one of the oldest gas pipeline networks in the country. Some of the pipes running under our streets are more than 100 years old. 

Massachusetts gas utility companies are required to report the location of gas leaks in their territories. In 2020, utilities reported 14,640 un-repaired gas leaks across the Commonwealth. Last year, these leaks released an estimated 5,753 metric tons of methane into the atmosphere. That is roughly equivalent to the emissions of 107,562 US passenger cars.

Utilities are allowed to charge ratepayers for the methane that leaks out of their distribution system. Massachusetts ratepayers handed over an estimated $5.4 million to cover the cost of leaked gas in 2020.

How are gas leaks prioritized for repair?

When a gas leak is reported, the gas utility must assess the leak to determine if it poses a safety hazard. Gas leaks are graded into four categories:

  • Grade 1: Potentially explosive leaks, should be repaired immediately.
  • Grade 2: Leaks that pose a potential future hazard, should be repaired within 12 months.
  • Grade 3: Non hazardous leaks, not required to be repaired.
  • Grade 3 Significant Environmental Impact (SEI): gas leaks pose  a “significant environmental impact,” and by state law must be repaired within 2 years.

Why focus on Significant Environmental Impact (SEI) gas leaks?

A 2016 Boston University study of gas leaks in Boston found that 7% of gas leaks are causing 50% of the damage. Twenty-five of Brookline’s 219 leaks are classified as Significant Environmental Impact leaks (SEI).

Newly passed legislation requires gas companies to identify SEI gas leaks and prioritize them for repair, but public pressure is needed to ensure these leaks are repaired as soon as possible.

Who creates the gas leaks maps?

HEET, a Cambridge-based nonprofit working to cut carbon emissions, generates gas leaks maps using data reported by gas utility companies. They have maps of every town in Massachusetts. Check it out here.


The Future We Want

To ensure a livable climate, we must transition away from fossil fuels to clean heating and cooking technology powered by renewable electricity. Mothers Out Front is asking utilities to adopt a “Triage and Transition” approach to our gas system. TRIAGE means repairing large volume and highly hazardous leaks as soon as possible. TRANSITION means directing resources to transition customers off of gas and onto affordable, safe, non-emitting, renewable sources of heating and cooling.

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