Longyearbyen tap water ban extends into 2026 over sulphate, nickel levels

Mayor says ‘completely new water mains’ may be needed to fix contamination

According to reporting by Karen McVeigh in The Guardian, the Longyearbyen lokalstyre first alerted the town’s 2,600 residents to the contamination in September 2025 after tests found manganese levels running 25 times higher than the 50 micrograms-per-liter limit recommended by the Norwegian Institute of Public Health. Even though manganese readings have since dropped, the drinking-water ban remains in place because sulphate and nickel levels were also found during 2026 to exceed recommended drinking-water limits.

Longyearbyen, in the Svalbard archipelago about 800 miles from the North Pole, draws its main drinking water from Isdammen, a 1.5-mile-long (2.5-kilometer) dammed lake also known as “ice pond.” The archipelago is warming at between five and seven times the global average rate, with autumn temperatures rising up to 4°C a decade.

Marjolaine Verret, a permafrost expert and associate professor in Arctic geology at the University Centre in Svalbard, said the contamination stems from the thawing permafrost and from the local shale bedrock, which contains a mineral called pyrite, or fool’s gold. “When pyrite came into contact with water and oxygen, it oxidised and generated acidity,” Verret said. “The acid produced can now leach heavy metals from these rocks into the waterways. The issue we’ve been having here in Longyearbyen is manganese, but other contaminants can be leached out from the rocks.”

The contamination is linked to two factors, researchers say: the thawing of permafrost — rock-hard ground that remains frozen all year apart from a so-called “active layer” that thaws in summer — and the geology of the former mining town. Higher temperatures linked to the climate crisis have thawed the permafrost, exposing new sections of bedrock that leach metals into the lake.

Mayor Terje Aunevik said drinking-water quality had never been good due to sediment, but the manganese levels had “gone ballistic.” Prolonged exposure to elevated manganese can cause neurological problems, particularly in children and infants. The mayor has commissioned an investigation into the water supply and said a “completely new water mains supply” may be needed.

Aunevik said potential fixes include installing a filtration system for Isdammen with a desalination plant as backup, or the reverse. Either approach would be “extremely expensive,” he said, and technically demanding in Svalbard’s conditions, where water temperatures often sit below zero. Aunevik added that while manganese levels were “not dangerous,” government guidelines had to be followed.

As an interim measure, the municipality has installed a free purified-water tank at the local supermarket, with water filtered by the town’s brewery, where residents can refill containers. The drinking-water crisis has generated considerable “noise,” Aunevik acknowledged, with some residents angry at the inconvenience.

Verret and other researchers have warned that the combination of thawing permafrost and pyrite-rich bedrock is not unique to Svalbard. “These ingredients [bedrock rich in pyrite and heavy metals] and thawing permafrost are present in other parts of the Arctic so this could be a first example of how climate change can impact freshwater, for example in northern Canada and Alaska,” Verret said.

Aunevik urged other small communities to begin preparing for similar disruptions. “In Norway, where we have always taken for granted that we can drink the water from the tap, it is challenging to start thinking that we need to carry our water like we do now,” he said. “Other small communities should be precautious and start thinking of what to do if it happens to their sources.”