Hamburg, June 8 – Several environmental organizations are expressing grave concerns about a potential mass fish die-off in the Elbe River this summer. Oxygen concentrations at the Seemannshöft measuring station near Finkenwerder have dropped to an ‘acutely fatal’ level, prompting urgent warnings.
Elbe River’s Oxygen Levels in ‘Acutely Fatal’ Range
The alliance “Lebendige Tideelbe” (Living Tidal Elbe), which includes the Federation for Environment and Nature Conservation Germany (BUND) and the Nature and Biodiversity Conservation Union (NABU), has raised the alarm. They state that even before the peak of summer, fish in the Elbe are already experiencing critically low oxygen levels, turning the river into a “death zone.”
Over the past few days, the oxygen level at the Seemannshöft measuring station has steadily declined, currently standing at 1.4 milligrams per liter. For fish to thrive, a level of six milligrams per liter is considered healthy. Anything below four milligrams per liter endangers young fish, and below two milligrams, survival chances are almost non-existent, according to environmental groups.
Data from the Hamburg water quality network also showed that oxygen concentrations at the Blankenese measuring station temporarily fell below two milligrams per liter on Monday. Similar values were recorded about two weeks later last year.
Dead Sturgeon and Eels Already Found
NABU fears that such low oxygen levels could lead to thousands of dead fish in the tidal Elbe. The Angler Association Hamburg has already reported the first findings of dead fish, including two sturgeon, several bream, and numerous endangered European eels.
Elbe Deepening Blamed as Primary Cause
The environmental alliance attributes the annual oxygen deficit primarily to the ongoing deepening of the river. BUND, WWF, and NABU are jointly demanding the creation of shallow water zones and the reversal of the latest dredging work for the Elbe deepening project. They argue that “the additional depth in the Elbe’s shipping channel is hardly used, but nature pays a high price.”
The environmental authority, in response to the low oxygen levels at the Blankenese, Seemannshöft, and Bunthaus measuring stations, stated that “local fish die-offs (especially fish larvae and juvenile fish) are very likely.” They acknowledge that the causes for the regular oxygen deficiency in the Hamburg tidal Elbe during the growing season are diverse.
Long-Term Study Shows 90 Percent Fewer Fish in Elbe Estuary
Fishermen in Hamburg and along the Elbe have long complained about declining fish catches. Scientific studies now corroborate their observations, with a long-term study indicating a 90 percent reduction in fish populations in the Elbe estuary.
This issue was also discussed on NDR 90.3’s “NDR 90,3 Aktuell” program on June 8, 2026, at 1:00 PM.