Shared Action Plan

HEET’s Zeyneb Magavi & Eversource President of Gas Business Bill Akley present solutions

HEET, Mothers Out Front, Columbia Gas, Eversource, and National Grid participated in the Large Volume Leak study and agreed, given the results, on these shared actions as the current best method to deal with large volume leaks in Massachusetts.

We are currently in Year 2 of the Shared Action Plan. Read our report on Year 1 (2019-2020) here. See our report on our 2018 Trial Year here


  • Grade-3 Large Volume Leaks (LVL) determined using leak extent as sole proxy method, at least for the first year.
  • Leak footprint evaluated with a consistent and defined method across utilities (i.e. either with CGIs/FIs, barhole or drillholes). Method to be decided by utilities.
  • Leaks over 10 years old not prioritized for repair unless it is LVL.


  • Leaks > 10,000 sq. ft. fixed within 12 months of determination by leak repair or main replacement.

    Harvard University’s Leith Sharp explains the complex system of the Large Volume Leak coalition

  • When 2,000 to 10,000 square foot leaks are discovered and verified, we will endeavor to repair them within two years with the exception of inaccessible or challenging leaks which shall be repaired when access can be gained.  If any 2,000 to 10,000 square feet leaks are on pipe that will be replaced through GSEP within five years, we will endeavor to eliminate the leak within three years.
  • An LDC (a gas utility) may choose to cap its environmentally significant leak repairs in any one calendar year at 7% of its total Grade 3 leak inventory as indicated in the previous year’s final quarterly leak report on file with the Department of Public Utilities.


  • For first year, at minimum, a statistically significant randomized sample of Grade 3-LVL leak repairs are FluxBarred prior to repair. Method of verification to be reassessed annually. See below.

Reporting (Department of Public Utilities)

  • On  GSEP reports, the number of known LVL leaks on each pipe segment.

    Rev. Mariama White-Hammond convenes the Large Volume Leak summit

  • On Annual Service Quality reports  the leak address, leak footprint, date leak was reported, LVL classification date and repair date.


  • Methods and results reassessed and adjusted annually for at least five years by a panel made up of utilities, HEET research team, and a mutually agreed-upon independent third party to provide recommendations to DPU.


Initial Year Collaboration to support the transition. Leak addresses, reports and repair dates of all high emitters shared with HEET so we can randomly survey 100 leaks to ensure consistency across utilities. FluxBar data forms shared with HEET for the first year so we can provide any needed assistance. Fluxbar results will allow for apples-to-apples comparison between leaks, progress to be benchmarked and further learning to allow for more efficient allocation of resources.

HEET researchers, supporters and the participating gas companies at the end of the summit

“Shared Action Plan” by HEET is licensed for open sharing and adapting under Creative Commons CC BY-SA 4.0.