environment
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
TL;DR
- Norwegian fish farms are releasing nutrient pollution equivalent to the raw sewage of tens of millions of people.
- In 2025, Norwegian aquaculture released 75,000 tonnes of nitrogen, 13,000 tonnes of phosphorus, and 360,000 tonnes of organic carbon.
- This pollution is comparable to the untreated sewage of 17.2 million people for nitrogen, 20 million for phosphorus, and 30 million for organic carbon.
- The fish sludge from nutrients can fertilize phytoplankton, leading to destructive algal blooms that deplete oxygen levels.
- Fjords are particularly vulnerable due to their semi-enclosed nature and already declining oxygen levels from global heating.
- Feed consumption by fish farms has increased by 14.6% over six years, contributing to the rising pollution.
- Seasonal variations aggravate the problem, with nutrient loads highest in summer when ecosystems are least able to absorb them.
- Officials rejected nine fish farm applications in a fjord due to concerns about increased emissions.
- The industry states that current production is within nature's carrying capacity and that they are working to minimize their environmental footprint.