Nearly 70 people were arrested during a protest at a coal-fired power plant in Bow Saturday.

The activists had marched onto the grounds of Merrimack Station, the largest coal-burning facility left in New England that is not set to retire.

Hundreds more people from across the region protested outside the plant’s main gate and in nearby Memorial Field, decrying the continued use of the fossil fuels that accelerate the harmful effects of climate change.

Listen to the sounds of the protest in the broadcast version of this story.

Bow resident Mary Fite brought her two young kids to the protest, joining chants of "climate justice now" and "shut it down."

“We breathe the air here, we play outside here,” Fite says. “We care about the town that we’re from, and I want them to know that we have a voice.”

The protest was orgainzed by nonprofits like 350 New Hampshire, Rights and Democracy, New Hampshire Youth Movement and Climate Disobedience Center.

It came at the end of a global week of protests in which millions of people, including in New Hampshire, rallied for governments to do more to rapidly lower carbon emissions.

New England now gets far less of its electricity from coal and oil than other parts of the country. But protesters like Rod Monroe say any coal use is too much, knowing the catastrophic effects of its carbon emissions.

“This is destroying our future, our ability to survive. We need to shut these plants down,” Monroe said. "And hope is dependent upon doing action. So we need to up our activity and do an action like this – be willing to put our lives out.”

As we spoke, a police helicopter flew overhead. It was part of a large multi-agency state and local law enforcement presence that spent hours monitoring the protesters.

They trailed marchers in squad cars and ATVs, flew a drone overhead and drove boats up the Merrimack River beside the plant.

Rod Monroe was part of a group of protesters who walked more than a mile down railroad tracks outside the plant, carrying buckets to symbolize their goal of removing coal from New England “bucket by bucket.”

They sang, beat their buckets like drums and chanted, "no coal, no oil, keep the carbon in the soil."

In August, a similar protest group allegedly stole some of Merrimack Station’s coal and dumped it outside the New Hampshire Statehouse. Organizers say at least one person was arrested Saturday on a warrant from that event.

The plant is owned by an out-of-state company called Granite Shore Power, which bought it from Eversource in 2018 as part of the utility’s state-mandated divestiture from its energy generation assets.

Protesters who walked down the tracks outside the facility Saturday received one initial warning from police to disperse. They did not, and continued on toward the plant with media and third-party legal observers in tow.

Several “no trespassing” signs were posted on a railroad spur leading to the plant, where it takes delivery of coal from Appalachia and overseas at least once a year. Along that spur, a line of police attempted to stop the activists and began arresting about half the group.

The rest continued up the railroad tracks toward the plant, where its large storage pile of coal was visible. Organizers say that pile dates to when Eversource owned the power plant.

At that point, at least a dozen state police wearing riot gear and carrying batons approached from the facility. The protesters put down their buckets, formed a circle on the tracks, linked arms and began to sing.

NHPR’s reporter was then told she would be arrested if she did not leave the area. As she did so, police began to detain the other protesters, binding their hands with zip ties, before transporting them off-site.

Police in Bow say the protesters face class B misdemeanor charges for criminal trespassing on posted property. A total of 67 people total were arrested, but no injuries or damages to property were reported.

The power plant makes up the bulk of Bow's property tax rolls. The New Hampshire Supreme Court recently ruled that the town overvalued the plant in 2012 and 2013, when Eversource still owned it.

In July, Bow agreed to a $10 million settlement with Eversource. It will result in about an 11 percent reduction in the town’s property tax revenue between 2020 and 2023.

Mary Fite, the Bow resident who attended the rally, says her town should work to divest from the plant.

"We're moving away from coal. There's been so many other technological advancements since this plant was built," she says. "The taxpayer can't take on this burden -- the town needs to diversify its funding and find a better way."

The plant is also facing a federal pollution lawsuit for the hot water it discharges into the Merrimack River under an outdated federal permit. Advocates say that hot water is hurting the ecosystem.

This month, a federal judge denied the plant's owners' bid to dismiss that suit, allowing it to move forward.

Coal and oil generally make up 5 to 10 percent of New England’s fuel mix – usually less than hydropower or other renewables. The region burns these fossil fuels, and uses plants like Merrimack Station, most often during very hot or cold weather, when electricity demand is high.

Utility officials reported that coal and oil use during the early 2018 cold snap caused enough emissions to negate 75 percent of the benefits of solar power in Massachusetts.

New England typically gets at least a third and sometimes more than half of its electricity from natural gas, also a fossil fuel, which emits about 40 percent less carbon dioxide than coal.

Activists like those at Saturday's protest don't support the use of natural gas as an alternative to coal and oil. Some who attended also denounced Liberty Utilities' proposed Granite Bridge gas pipeline and storage facility.

That project, mostly in Rockingham County, is nearing its state approvals process.

The second-largest source of electricity generation in the region is nuclear power -- that now comes from just two plants, Seabrook in New Hampshire and Millstone in Connecticut.

Electricity generation accounts for 20 percent of New Hampshire’s greenhouse gas emissions, according to the state climate change program. The transportation sector is the largest contributor, at more than 40 percent.

This story was updated Monday, Sept. 30, with more detail and audio.