Environmental groups criticize the planned irrigation of new trees in the Rumpenheimer Schlosspark by drinking water from the city of Offenbach.
A water pipe under the park paths, about 1000 meters long, with at least eleven water tapping points – cost 150,000 euros: this is how the planners in Offenbach envision the rescue of the Rumpenheim Palace Park. In the past year and a half, the city had had to cut 450 of about 1,500 trees in the historic green area on the Main – they had died as a result of heat, drought and the resulting soot bark disease. However, there is criticism that the city wants to water new trees in the park permanently with drinking water in the future.
“It is problematic if valuable drinking water is used to water the trees,” says the spokesman for the Naturschutzbund (Nabu) Hessen, Berthold Langenhorst. Irrigation makes sense, but it is essential to use process water – such as rainwater captured in cisterns. According to Langenhorst, the increasing tapping of drinking water in water production regions such as the Hessian Ried leads to problems for flora and fauna.
Lynn Sophie Anders from the Hessian regional association of the BUND has a similar opinion. According to Anders, watering with drinking water can “be accepted as a temporary solution” – in the long term, however, she is asking the city of Offenbach to “use sustainable water management that does not use valuable drinking water for tree irrigation”. She suggests pumping water from the nearby Main.
Peter Schneider also thinks this is a possible way. The former Mayor of Offenbach and Green Party politician lives in Rumpenheim and can observe the decline of the park up close – and as a chairman of the Water and City Administration Association in Offenbach (ZWO), he is a specialist. Schneider recalls times when it was customary for a tanker to draw water in the Main in the morning and thus water city trees. “Drinking water is a precious resource,” he says. Watering trees with it “cannot be the solution”.
The city is currently still working on a concept that should show how as many different, climate change-resistant park trees can be replanted in the coming years. The first step in autumn is to add 120 new trees. The park paths under which the future water supply is to run will also be renovated for 50,000 euros. At the request of the Frankfurter Rundschau, it was said that drinking water should flow through the irrigation pipes in the park.
There is also criticism of this in our own administration. Heike Hollerbach, head of the Environment Agency, would find it better to use rainwater, even if it was also rare. Above all, it is important that unsealing is used to ensure that more water seeps into the ground again in the urban area instead of disappearing into the sewer system – because only in this way can the greatly reduced groundwater level rise again. Unsealing is part of the urban climate adaptation strategy. Hollerbach, however, is cautious about the use of main water: it is questionable whether the water quality is good enough.
Pumping off main water must be approved by the Aschaffenburg Waterways and Shipping Authority. When asked there, it is said that permits are issued on a regular basis – for agriculture or allotment garden associations, for example, that water with river water.