Status: 05/06/2022 10:07 a.m
Spring was far too dry in many places in Germany – again. Creative ideas for drought management are needed. Contingency plans for dry streams, parking garages with water storage, rainwater playgrounds.
The Sasselbach between Mainz and Worms has almost disappeared. Only a trickle winds its way down through the vineyards towards the Rhine. Springs, ponds and streams are drying up everywhere in Germany, as is the case here. More than 1000 surface waters are currently noisy ARD project #ourwater too dry.
The quiet dying of lakes and streams will increase, “in the low mountain ranges as well as in the lowlands and especially in the urban areas”, predicts the hydrobiologist Mario Michael Sommerhäuser: “We have to live with the fact that not every body of water can be preserved in climate change as it is today – there will be more and more drying up water in the summer half-year.”
For years it has been getting warmer and drier in Germany. As an expert from the German Association for Water Management (DWA), summer houses now have to deal with how droughts in Germany are to be managed, for example by rationing water.
#ourwater: Participating science project
The small stream in the village or the grove at home already has little water, unlike ten years ago, sometimes the trickle even dries up completely in summer? These observations are of interest to the water ecologist Hans Jürgen Hahn from the University of Koblenz-Landau: “The idea is that you actually get an overview of how drought affects the area, especially on a very small scale.”
He accompanies them ARD-Action #our water scientifically and calls on people all over Germany to take part in filling the gaps between the official blanks. The more people participate and fill out a simple form online, the more meaningful the interactive map in which the reports are recorded will be. The online form you’ll find here.
“Think of the water first”
He wants to have contingency plans drawn up for water that is drying up. There is already one for high and low water in the Main. But things have to be fundamentally rethought, says Sommerhäuser: “Up until a few years ago, urban planning was always based on streets and buildings. Now we have to think about water first when planning.”
Up until the 1990s, planners were always concerned with diverting water from the landscape, adds groundwater ecologist Hans Jürgen Hahn from the University of Landau. In the meantime, that has reversed. “Now we have to keep it level.”
At Guntersblum, drainage ditches often run through the vineyards. The water immediately drains into the valley and then down the stream into the Rhine. “Instead, we would need more structures on the slopes, such as hedges and terraces in the steeper areas, which slow down the drainage of water,” says Hahn. This also applies to agriculture. In agriculture, but also in residential and commercial areas, one must ensure “that the water seeps away slowly and does not disappear into the nearest sewage system”.
Parking garages with water storage
Parking lots should be more permeable to rainwater. More green strips and green roofs are needed. Hamburg now has rainwater playgrounds in which the water stagnates during heavy rain and slowly seeps away. According to Sommerhäuser, model tests with multi-storey car parks, in which one floor is intended to store water, are also exemplary. Moors and forests are also important to keep the water in the landscape.
But the forests in particular lack water. “For example, in the alluvial forests on the middle Elbe, we see that trees of all ages are extensively damaged by drought stress and die off,” says Tobias Schäfer from the WWF. One SWR-A survey of 240 German foresters showed that more than 95 percent of those surveyed found that the water supply in their forests had deteriorated over the past ten years. The federal chairman of the Federation of German Foresters (BDF), Ulrich Dohle, must stop the “decades of drainage policy”. The contribution that forest owners pay annually to the water and soil associations so that “their forests are drained against their will” must be repealed.
ARD theme day #Our water: documentation “Up to the last drop”
Thomas Reutter/Danie Harrich, SWR, daily news at 12:00 p.m., March 16, 2022
If necessary, the swimming pool remains dry
Agriculture must also adapt, says groundwater ecologist Hahn: Irrigation must be optimized and modern irrigation techniques used. Also, irrigation should only be done at night, when much less water evaporates. This would reduce water consumption in agriculture by up to 80 percent. “In the future we will need agriculture that works the soil in such a way that it absorbs the water more quickly and can hold it better.”
The experts in water management require industry and trade to reuse used water, so-called gray water. The swimming pool in the garden will have to remain dry in an emergency, Sommerhäuser said. And despite all the ideas, plans and measures, it will probably be decades before bodies of water like the Sasselbach return once they have disappeared.