Author(s): Robert Duval. Published on July 1, 2019.

Big Assist

Nearly a year after an unprecedented natural gas event upended three Massachusetts communities, fire officials reflect on the critical importance of incident command and regional mutual aid


Shortly after 4 p.m. on September 13, 2018, 911 calls began to stream into the fire alarm office in Lawrence, Massachusetts, as residents throughout the town reported fires, explosions, and the smell of natural gas. Brian Moriarty, chief of the Lawrence Fire Department, had finished his shift and was planning to meet a few friends when he learned of the fires breaking out across the city. He responded to the first incident he heard about, a structure fire in a part of town where numerous homes were reporting issues with natural-gas fueled boilers, furnaces, and hot water heaters. En route, additional reports came crackling over the fire department radio in his car. He arrived to find a fire in a large multifamily building with residents evacuating. As other firefighters arrived, reports continued to come over the radio of yet more fires and explosions, especially in the area of South Lawrence. What is going on here? Moriarty wondered to himself—had there been some kind of large-scale malfunction of the city’s gas system? He knew the town would soon require mutual aid to handle the volume of fires and other incidents that were occurring.

MANAGING CHAOS A Lawrence police officer directs traffic as firefighters work to knock down a gas-related fire. More than 60 fires and at least three gas explosions rocked the communities of Lawrence, North Andover, and Andover in a single afternoon. At top right, a Lawrence man died when a gas explosion in a home caused a chimney to fall on the vehicle he was sitting in. Photographs:Getty Images

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The afternoon grew even stranger. While in command of the multifamily structure fire, Moriarty was informed by fire department dispatchers that the neighboring Merrimack Valley communities of Andover and North Andover were also experiencing fires, explosions, and reports of strong odors of natural gas. All three towns are in Essex County, in eastern Massachusetts, and are part of a county-wide plan that spells out what a fire department’s response should be based on an escalating number of alarms generated by a fire or other event: two alarms, three alarms, and so on, up to 10 alarms. The gas events in the three communities had overwhelmed the county’s response plan, and the fire departments in Andover and North Andover were unavailable for response on subsequent alarms in Lawrence. Moriarty would have to look for help somewhere else.

on using incident command

Chief, Lawrence Fire Dept.

"We practice the ICS process in everyday operations, and it was used during the whole Merrimack Valley incident.

“An important part of ICS is that the roles people take on are functional and not based on rank. I had officers assuming command roles that they don’t usually get to assume—a lieutenant was in charge at a working fire rather than a chief officer. I put a firefighter paramedic, not an officer, in charge of staging because I knew he had the training and skill to run it without taking guff from people—and he did an outstanding job. Players changed, but the process remained the same throughout the event.”

Deputy Chief, North Andover Fire Dept.

"With this mostly being a fire incident, the other responders and emergency management agencies that were involved allocated resources to assist. As our off-duty crews arrived and multiple agencies were coming into town, I set up a staging area at our middle school. When that was set up, dispatch would communicate directly with them to send trucks to new incidents. Having all of the agencies present and having the ability to share ideas to accomplish the strategies was very effective.

“As the events slowed and fires came under control, I transferred command to another officer who ran operations in North Andover while I moved to the regional unified command in Lawrence. Having the ability to increase the amount of people in the community for an event like this while having my crews well-versed in ICS made the event run as smoothly as it could, with no loss of life and only minor injuries."

Chief, Andover Fire Dept.

"The emergency operations center in Andover was activated within 30 minutes of the incident. All available town department and division heads began actively responding to the needs of the incident, and pre-planning the needs for a transition from response mode to recovery mode. This action allowed the town to respond to the disaster much more efficiently and effectively during the first seven days."

He instructed his dispatchers to seek mutual aid from communities north of Lawrence, and to send single pieces of Lawrence Fire Department apparatus to each incident until sufficient resources could be gathered. He also stressed that radio traffic needed to be kept to a minimum due to the number of units working simultaneously at several serious incidents.

Fire officials in Andover and North Andover were coming to a similar realization. Michael Mansfield, the fire chief in Andover, and Graham Rowe, deputy fire chief in North Andover, were able to use some of their run cards for mutual aid, but quickly exhausted those resources. As Lawrence looked for help to the north, the other two communities sought assistance from communities to the south.

That was only the beginning of a long night and a prolonged aftermath for responders in the trio of communities affected by what would come to be known as the Merrimack Valley gas explosions, and for the hundreds of mutual aid responders who eventually assisted. As Moriarty had guessed, and as investigators would later determine, work on a natural gas main in Lawrence—conducted by the utility, Columbia Gas of Massachusetts—had caused a pressure spike throughout the gas systems in all three towns. Gas was forced under tremendous pressure into homes, businesses, and other occupancies and was ignited by appliance pilot lights and other sources—residents recounted hearing ominous hissing noises throughout their neighborhoods moments before buildings exploded. Over the first several hours of the incident, Andover reported 21 structure fires, with 11 in North Andover and nine in Lawrence, which also had five buildings that exploded. Fires attributed to gas leaks from appliances and boilers tallied 131 in Andover, 55 in Lawrence, and 22 in North Andover. Across all of the affected communities, one civilian died: an 18-year-old Lawrence man who was killed when the vehicle he was sitting in was crushed by a brick chimney that collapsed in a house explosion. An estimated 25 injuries occurred, including seven firefighters—three from Lawrence and two each from Andover and North Andover.

The magnitude of the event underscored the need for an effective mutual aid plan capable of acquiring resources from local, regional, and state participants—and even beyond. From September 13–16, mutual aid fire resources were drawn from Massachusetts (246 assets from 199 communities); New Hampshire (92 assets); and Maine (one asset). More than 200 communities and law enforcement agencies would eventually commit resources to the area. Assets included 180 engines, 68 ladders, and 50 command vehicles. Hundreds of fire, emergency, law enforcement, and gas utility personnel responded to hundreds of calls in the affected communities.

In the months since the incident, all three chiefs agree on several key points of incident command: request assistance early and often; maintain radio and organizational discipline; organize resources and put trained people in key command roles; and document all important events and requests, and maintain this log until the event is terminated. All three stress the critical importance of a clearly defined incident command system, or ICS, which places fire and emergency personnel at the scene in charge of certain portions of the event. Executed correctly, the ICS can streamline and improve lines of communication, as well the organization of critical resources, all resulting in a more efficient and effective management of the emergency.

The role of ICS in the management of the Merrimack Valley fires was key to preventing a difficult and complex event from becoming a catastrophic one. “ICS was used during the whole incident,” Moriarty told me in an interview weeks afterward. “We practice the process in everyday operations. It all worked like a well-oiled machine.”


The chaotic first minutes of the event were typified by the experience of Dan Rivera, the mayor of Lawrence, who was in Boston for a training when his phone rang. According to a March article in Boston magazine, the caller was the city’s police chief informing Rivera that there were fires across Lawrence, as well as in Andover and North Andover. “I’ve never seen anything like this before in my life,” the police chief told him. Rivera left the training and began the drive north to Lawrence, trying to fight his way through rush-hour traffic.

WIDESPREAD IMPACT Top left, as utility workers look on, an Andover police officer exist an evacuated house after checking that the gas had been turned off. Below, firefighters in North Andover inspect a home after it was damaged by a gas explosion and fire. Photographs: Top, AP/WIDE WORLD; Bottom: Getty Images
He called the city’s water and sewer commissioner, who told him whatever was going on had nothing to do with work on water mains. Rivera called a government relations representative for Columbia Gas of Massachusetts, but the man told Rivera he had no idea what he was talking about. Then he called Dana Argo, the utility’s operations manager. According to Boston magazine, Rivera recalled the conversation this way:

Argo: “Hey, what’s going on?”

Rivera: “I don’t know. You tell me what’s going on.”

Argo: “What are you talking about?”

Rivera: “We have multiple fires.”

Argo: “I don’t know what you’re talking about.”

Rivera: “You need to find out and call me back.”

As city and utility officials figured out what was going on, word spread though the region’s responder community about what was happening in the Merrimack Valley. Paul Parisi, the New Hampshire state fire marshal and a longtime friend of Moriarty’s, phoned him in the early hours and offered assistance from his state, which Moriarty gratefully accepted. Initially, a task force of six engines, three ladders, four ambulances, and five chief officers was dispatched from several communities in southern New Hampshire, followed by several other task forces as the incident continued. These assets responded to all three communities and later to a primary staging area that was created in Lawrence.

By all accounts, the early phases of the incident were chaotic and overwhelming for just about everybody involved. At the height of the incident in Lawrence, eight building fires burned simultaneously, and five buildings had suffered some type of explosion. One explosion caused a masonry chimney to collapse onto a car, killing one of the vehicle’s occupants, an 18-year-old man. The Andover Fire Department was in the process of responding to 11 simultaneous building fires, part of a total of 79 incidents in the first hours of the event that injured two civilians and two firefighters. In North Andover, five simultaneous structure fires occupied the on-duty staff and apparatus. Before mutual aid arrived, the town’s fire prevention officer responded alone in a fire department SUV to a working structure fire before additional units could assist.

At 4:42 p.m. on Thursday, the chiefs requested task forces through the Massachusetts Statewide Mobilization Plan to respond to the affected communities. This plan musters predetermined task forces, strike teams, and command officers and deploys them to towns or regions requesting assistance with large-scale or long-term incidents. Each task force consisted of six engines and two ladder trucks, with two chief officers and approximately 26 firefighters. The chiefs identified a large parking lot beside a closed movie theater in Lawrence as the regional staging area. All apparatus, staff, and additional assets would respond to the staging area and would be deployed from that location.

As fire resources mobilized, police chiefs in the three communities were also putting their mutual aid plans into effect—and, as with the fire departments, those plans were soon overwhelmed by the number of calls for assistance. As the calls for police mutual aid expanded, some of the arriving assets were also routed to the staging area in Lawrence to assist fire and EMS units.

As the staging area was established, the impacted communities were beginning to grasp the magnitude of the incident and what would be necessary to manage and subdue it. As outside resources arrived at the Lawrence staging area, responders and government agencies—including canteens, lighting units, municipal inspectors, and scores of utility workers—began to set up a unified command system, where all resources, regardless of their tasks, work under a single command structure toward a common goal. From here, fire, police, EMS, and utilities, as well as state and local government representatives, met to delegate tasks and put plans in place to meet the immediate needs of the region and plan for the next several 12-hour operational periods. The Massachusetts State Police command post vehicle was used as the unified command headquarters at the theater parking lot. Additionally, each town established its own local emergency operations center, or EOC, to address community needs.

As darkness fell on Thursday evening, units were still being deployed to calls for assistance as they came into the Lawrence staging area. In addition, teams made up of police, fire, and utility crews were being sent into the affected neighborhoods to secure gas service in buildings and residences—more than 8,000 gas meters were inspected and shut off. The decision was made to cut electrical power in the affected areas as a precaution until the gas could be secured. The loss of both gas and electrical service resulted in many residents leaving their homes—estimates put the number of people displaced at approximately 8,600—and included people who were not impacted directly by the initial emergencies. Crews canvased the area throughout the night looking for hazards, shutting off gas in individual units and securing hazardous conditions.

Canteen services from Massachusetts, New Hampshire, and Maine, along with several local establishments, set up in the staging area to feed responders. Many of these units remained at the site for several days.


The extent of what had occurred become apparent Friday morning as the initial incidents were brought under control and surveys of the neighborhoods were completed. As emergency responses slowed to near-normal levels in each community, utility crews and state and local inspectors began the long-term work of restoring gas and power to the region.

Fire, police, public works, state and local inspectors, and utility crews worked through the weekend to survey the damage and begin utility restoration efforts throughout the region. Inspectors examined gas-fired equipment and the associated piping to individual addresses and complexes and determined where and when the restoration process would take place. If there was damage to either piping or equipment, that equipment was tagged for replacement, and utility restoration was not permitted until the equipment had been replaced. A total of 5,000 homes and residences were surveyed or searched by these teams to determine the levels of damage.

During the initial hours of the incident, eight structural firefighting task forces were deployed to assist Lawrence, Andover, and North Andover with suppression efforts. In the days that followed, an additional 11 task forces from Massachusetts and two from New Hampshire responded to the area to assist. The most far-flung resources came from the town of Southbridge, Massachusetts, 80 miles south of Lawrence. The task forces were assigned 12-hour operational periods before being relieved. In each operational period, three task forces responded to the area. Two were deployed to Lawrence and one covered Andover and North Andover.

Power was restored to neighborhoods early Sunday morning, September 16. Later that morning, several task force units worked alongside units from the Lawrence Fire Department to battle a three-alarm fire in an apartment complex on Diamond Street. The day before, Moriarty had argued to let residents back into the neighborhoods on Saturday to help identify potential problems related to the gas surge. “We were concerned about an electrical fire starting from a damaged device such as a boiler or furnace,” he said. “Letting people back in meant they would be home to see or smell something and could call us right away. And they could let us in the homes that were locked.” Ultimately, though, the decision was made to wait until Sunday morning to let people back in. When a resident returned home Sunday they found the building full of smoke—the fire turned out to be from a cable in a floor/ceiling space and not the result of a damaged boiler or furnace. Survey teams continued to canvas neighborhoods after power was restored to check further for hazards and damage from the earlier gas overpressurization incident and to assist residents who had returned to their homes.

RECOVERY AND REPAIR Utility crews complete work on a gas line in South Lawrence. More than 44 miles of gas lines had to be replaced, tested, and returned to service in the months following the Merrimack Valley gas explosions. Photograph: Getty Images

All of the mutual aid resources were demobilized by early Monday morning. As fire and EMS units were released from the staging area, the spaces formerly occupied by apparatus were quickly taken over by utility crews and excavation equipment. Their work of replacing underground mains, meters, and appliances would last for the next several months. 


Once the emergency response phase of the incident was complete, the community assistance phase began. Again, according to participants and observers, a robust management system was employed that allowed the many agencies involved to work together to assist citizens and businesses to restore a semblance of normalcy to their communities.

In the weeks and months following the incident, for example, communities in the region, working with state agencies, established several long-term shelters and manufactured home/RV parks to house thousands of displaced residents as the gas distribution system was repaired—a six-month process whereby more than 44 miles of underground gas pipe had to be replaced, tested, and returned to service. The Lawrence Fire Department assigned utility vehicles to the parks to provide fire and EMS services while the temporary housing was occupied. In the South Lawrence neighborhood, the epicenter of the gas emergency, LFD also staffed two extra engine companies, one ladder, a deputy, and two roving cars to check for road blockages and help respond to medical calls as construction continued to replace the underground pipe network.

In North Andover, fire officials were also assigning additional staffing. During restoration, fire department staff were in the areas where work was being conducted, and responded to sites where road access was limited due to gas pipe replacement work. An additional engine company was dedicated to any gas incident calls. A housing site of 60 recreational vehicles included two firefighter/EMTs assigned round-the-clock for fire and EMS protection.

HELPING HAND Massachusetts Army National Guard members load hot plates to be distributed to Merrimack Valley residents the week after a gas disruption displaced thousands and left many more residents without gas service for cooking or heating. Photograph: Getty Images

In the weeks immediately following the gas incident, members of the Massachusetts Army National Guard, as part of the state's relief effort, distributed thousands of electric hot plates and space heaters to residents without gas service—though this effort came with snags of its own. Inspectors found that many homes had outdated or underpowered electrical systems that could not safely handle the load required by space heaters, and far fewer were distributed than planned. “If [inspectors] don’t feel it’s safe, we don’t give them a space heater,’’ Moriarty told The Boston Globe. “We don’t want to make things worse.’’

Irate residents threatened to use kerosene space heaters instead, which are illegal in Massachusetts but are sold in neighboring states. The state fire marshal's office responded with a public reminder that kerosene space heaters are not allowed, and issued a tip sheet on hot plate and space heater safety.

Organizers of the relief effort, including the gas utility, were forced to get creative to meet the needs of the affected citizenry. To preserve local hotel rooms for use by displaced residents, Columbia Gas of Massachusetts arranged for a cruise ship to anchor in Boston Harbor to house hundreds of utility workers brought in from throughout the northeast US to complete the work. At Thanksgiving, the gas utility organized more than 25,000 meals that were served to displaced residents and to those who did not have gas for cooking.

Despite the gesture of goodwill, Columbia Gas has been widely and publicly excoriated for steps it took leading up to the disaster, and for its slow-footed handling of the event once it struck. The state’s governor, Charlie Baker, was so angered by the Columbia Gas response that he declared a state of emergency the day after the first fires broke out, and put another utility, Eversource, in charge. Three weeks after the incident, following a review of internal Columbia Gas documents, Massachusetts Sens. Ed Markey and Elizabeth Warren issued a statement saying the utility did not “properly contemplate the possibility that a disaster like this could occur, did not have sufficient safety measures in place to prevent a disaster, and was not prepared to respond.’’

State fines for Columbia Gas pipeline violations may total $100 million. According to published reports, Columbia Gas has received more than 23,000 claims related to the gas explosions and fires, and in May the utility announced it had reached an $80 million settlement with Lawrence, Andover, and North Andover that will allow the communities to make remaining repairs. Much of the restoration work had been completed by the end of 2018, with remaining work consisting of replacing heating units in several hundred homes following the 2018–19 heating season, as well as repaving roads dug up as part of the pipe replacement work. Estimates of the total cost of the event approach $1 billion.

While the scope and impact of the Merrimack Valley incident pales next to megaevents such as major wildfires, its complexity and unusual dynamics presented responders with a set of unique challenges. It’s not difficult to imagine what might have happened had the three towns not communicated and instead gone off on their own, without implementing the ICS. A freelance approach could have resulted in duplication of mutual aid requests, unavailable resources, overwhelmed communication systems, and equally overwhelmed incident commanders and local officials. Had a statewide mobilization plan not existed, the response could have taken on Wild West aspects; resources self-dispatching could have resulted in an all-or-nothing availability, with most arriving at the onset and few available later in the incident. Having structured plans in place, locally and at the state level, made the response to this incident much more efficient, easing the burden on local responders and government officials—and, ultimately, on the residents of the Merrimack Valley. 

ROBERT DUVAL is northeast regional director and a fire investigator at NFPA. Top photograph:

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  • Code Factor NFPA standards play an important role in planning for and managing events like the Merrimack Valley gas explosions.