Norwegian fish farms polluting fjords with waste likened to ‘raw sewage of millions of people’

Exclusive: ‘Fish sludge’ in coastal waters now has nutrient levels equivalent to those in untreated effluent of country the size of Australia, report finds Norwegian fish farms are filling fjords and other coastal waters with nutrient pollution equivalent to the raw sewage of tens of millions of people each year, a report has found. Norway is the largest farmed salmon producer in the world, and nutrients in fish feed are excreted directly into coastal waters. Analysis from the Sunstone Institute found that Norwegian aquaculture released 75,000 tonnes of nitrogen, 13,000 tonnes of phosphorus and 360,000 tonnes of organic carbon in 2025. The nutrients are equivalent to those contained in the untreated sewage of 17.2 million people for nitrogen, 20 million people for phosphorus, and 30 million people for organic carbon, the report found, raising fears of destructive algal blooms. “Norway is a small country of just 5.5 million people, and the output of aquaculture pollution in terms of these three nutrients is three to five times larger than the population,” said Alexandra Pires Duro, a data scientist at Sunstone and author of the report. “The faeces, the uneaten feed, the ur