Brown tap water on Læsø island fails quality standards despite being safe

Residents on the Danish island of Læsø have reported brown, murky tap water in recent days, forcing some to rely on bottled water and avoid washing clothes, DR reports. While tests confirm the discoloured water is not harmful to health, experts say it falls short of expected Danish drinking water standards.

Professor Hans-Jørgen Albrechtsen of DTU’s Institute for Water and Environmental Technology stated that although the water poses no health risks, its appearance and quality are unacceptable. “Danish drinking water should be clear. It should not have a colour or a taste, so in that sense, the water does not meet the expectations we have for drinking water. It is not okay, and something should be done about it,” he said.

Læsø’s water supplier, Læsø Forsyning, attributed the issue to increased water consumption during the Easter holiday, which dislodges organic substances—such as humus and okker—from the pipes, turning the water brown. The company claims regular testing shows the water meets all regulatory limits, but residents like Preben Jensen, a lifelong Læsø inhabitant, remain frustrated. “One day the water is clear, the next it’s almost like sludge. We buy bottled water during these periods and avoid bathing or laundry because it stains clothes yellow,” Jensen said.

Jeannette Klitgaard Andersen, chair of Læsø Forsyning’s board, advised residents to run their taps for 5–10 minutes to clear discolouration but acknowledged persistent issues should be reported. Mayor Niels Odgaard (K) stated he would intervene if the problem became chronic but currently views it as intermittent.

Albrechtsen suggested the recurring discolouration indicates inadequate filtration, particularly during low-usage periods when sediments accumulate. “If this is the cause, it suggests the water treatment plant hasn’t removed these substances sufficiently during quieter periods, allowing them to build up over winter,” he explained.