LANESBOROUGH, Ireland — For most of the 20th century, the brown plains of the Irish midlands were a fuel mine. Drained, stripped and milled, the bogs fed power stations and filled the plastic sacks of briquettes stacked outside every filling station in the country. The last industrial harvest ended in 2020. Since then, the state company that did the cutting has been putting the water back.
By the end of this summer, Bord na Móna had rewetted about 18,000 hectares of former production bog out of 33,000 it has committed to restore by 2030, by blocking drains, building low peat dams and allowing the water table to rise to the surface. On Friday, researchers from Trinity College Dublin published the first multi-year measurements from 11 of the restored sites, and the results were better than many expected.
“A drained, bare cutaway bog emits around 20 tonnes of carbon dioxide per hectare per year,” said Aoife Ní Cheallaigh, an ecologist at Trinity who led the monitoring. “Within three years of rewetting, that falls to roughly zero. On four of our sites it has gone negative. The bog is taking carbon in again.”
Ireland’s degraded peatlands are estimated to release about 11 million tonnes of carbon dioxide a year — comparable to the country’s entire passenger car fleet. The government counts peatland restoration toward its legally binding target of cutting emissions 51 percent by 2030, a target it is currently on course to miss by a wide margin.
The transformation is visible from the road. Where the land was a dark corduroy of milled peat, there are now sheets of shallow water, stands of cotton grass and, on the oldest sites, the first bright green cushions of sphagnum moss, the plant that builds peat. Snipe and curlew, both in steep decline in Ireland, have returned to several sites, said Siobhán Ní Bhriain, an ecologist with the company.
Not everyone in the midlands welcomed the change. About 1,500 jobs disappeared with the harvest, and the company has been accused of moving too slowly on promised alternatives. Declan Mulrooney, 58, drove a peat harvester near Lanesborough for 31 years and now works part time on a restoration crew. “I spent my life draining this and now I am blocking the drains,” he said. “The money is worse. The work, I will say, is more interesting.”
Dr. Ní Cheallaigh cautioned that the carbon gains are fragile. Rewetted bogs emit methane, a potent greenhouse gas, in their first years, and a severe drought could dry out the surface and reverse the progress. “This is not a switch,” she said. “It is a patient.”
At dusk on Thursday, a flock of golden plover settled on one of the flooded fields. “Thirty years ago you would not have seen a bird out there,” Mr. Mulrooney said. “There was nothing for them. Now there is water.”
A version of this article appears in print on Oct. 11, 2026, Section A, Page 2 of the European edition with the headline: Ireland Is Drowning Its Bogs on Purpose, and the Carbon Math Is Starting to Add Up.
