The National Transportation Safety Board (NTSB) has determined that Columbia Gas of Massachusetts’ deficiencies in management and oversight led to overpressurization of a natural gas distribution system which resulted in a series of fires and explosions in Merrimack Valley, Massachusetts.
The Sept. 13, 2018, accident occurred after high-pressure natural gas was released into a low-pressure gas distribution system in the northeast region of the Merrimack Valley. One person was killed and 22 people, including three firefighters, were transported to area hospitals. The system over-pressure damaged 131 structures, including five homes that were destroyed.