Phillips, who credits gas companies for working hard to fix gas leaks, said his work captures only a hazy picture of leaking gas in Boston; he drove down only one side of streets, and gas readings depended heavily on wind and other weather. The amount of methane in the air also does not directly reflect what is happening underground. For example, a large amount of gas could be trapped underneath a street and only a small amount makes it to the surface.
“There are a lot of unknowns,’’ said Phillips. He and Jackson have put sensors on Boston buildings to understand the collective effect of gas leaks in the city — and how much escapes to the atmosphere.
Shanna Cleveland of the Conservation Law Foundation, which has a natural gas leak report coming out soon, said the state Department of Public Utilities could require timelines for gas companies to repair various grades of leaks and improve upon accelerated reimbursement rates for gas companies that replace old gas lines.
A bill sponsored by state Representative Lori Ehrlich of Marblehead that would require a timeline for the most serious leaks to be fixed and require utilities to notify police and fire of the locations of leaks unanimously passed the House in June and is before the Senate.
Ehrlich said better regulations are needed for gas pipelines. “If everyone could see methane, I doubt if there would be any leaks left,” Ehrlich said. “Can you imagine if it came out red?”