Too little oxygen in the Elbe: warning of mass extinctions

Created: 06/30/2022Updated: 06/30/2022, 16:11

The sun sets over the Elbe and the Landungsbrücken.

© Christian Charisius/dpa/image archive

When the temperatures are hot, the oxygen in water bodies often becomes scarcer.

This is also the case in the Elbe.

That's why a lot of fish are dying there at the moment.

Several environmental organizations warn of serious consequences and have a clear demand.

Hamburg – The environmental organizations BUND, Nabu and WWF are sounding the alarm with a view to numerous dead fish in the Elbe.

Due to the current lack of oxygen in the Elbe, a dramatic fish kill is currently setting in, said the associations that are part of the Living Tide Action Alliance on Thursday in Hamburg.

"In the entire port area as well as up to Wedel and far behind the Bunthäuser Spitze, the oxygen concentration has dropped to values ​​of less than two milligrams per liter - an absolutely deadly situation for the Elbe fish."

The associations fear that in the long term an entire ecosystem will die as a result.

"For years, the offspring of the smelt, which used to be found in large numbers, has been destroyed in the summer by the poor oxygen levels in the Elbe - now it is increasingly affecting the old fish and other fish species." Flounders, plaice, asp and shad are also dying in large numbers.

The environmentalists are convinced that the deepening of the Elbe will make the situation in the Elbe even worse.

For example, the injection ship "Akke" whirls up silt in the river bed on behalf of the Hamburg Port Authority (HPA) so that it is washed away by the current.

"In the already murky soup of the Elbe, this is the death knell for many things that are still alive in the Elbe.

The Akke must now be connected to the chain immediately and the dredging work, which will be permitted again in principle from July, must be suspended until further notice," the environmental associations demanded.

The HPA rejected the allegations.

The dredging was limited to the areas absolutely necessary for nautical purposes and was carried out using the most modern and gentle methods, the HPA said when asked by the dpa.

"The HPA only uses devices that remove sediment from the river, but do not stir it up."

These included suction dredgers, which sucked the sediments directly from the bottom of the river without stirring them up.

These sediments are taken to areas outside the port where there are no problems with oxygen levels, it said.

In the case of particularly sandy subsoil, the HPA can also use water injection devices all year round.

Since it is sand, no fine sediments are distributed in the water column.

"At the current time there is no water injection." dpa