Germany: one year after the floods, the Ahr valley wants to “think about the future”

The imposing Steigenberger Hotel was known for its spa treatments, casino, and riverside galleries. The large white building still sits enthroned on the banks of the Ahr, but in front of the verdant park which housed the residents of the sanatorium, wooden planks have replaced the windows, the galleries are ripped open, and in the already hot air of this beginning of July remains a sad feeling of an abandoned palace. A year ago in Bad Neuenahr-Ahrweiler, in the German state of Rhineland-Palatinate, the flood brought everything to a standstill.

In one night, torrential rains overflowed the Ahr, a pretty shallow river, whose meanders are planted with vines that produce one of the best wines in Germany. Today, the valley seems to be slowly recovering from the disaster. . But the damage is enormous. Entire villages are still under reconstruction, around 17,000 people have lost their homes, and according to the insurer Munich Re, the cost of the destruction amounts to 33 billion euros for the Ahr valley region alone. .

In shorts and light hiking shoes, tourist guide Horst Gassen walks the streets of Ahrweiller to show the scars of the ravages. But most of the work is done. The tens of thousands of cars that littered the streets, washed away by water, have been removed, the mud cleaned, and the roads are gradually reopening. However, almost everywhere in the city, the buildings still testify to the extent of the drama: the covering of the walls has been removed where the water has stopped. One meter fifty, two, sometimes three above the roadway, the scale of the phenomenon can be read in a clear line between what remains habitable and what is no longer. Horst Gassen remembers that night, he remains incredulous. “It was not a flood, but a real tidal wave, the water rushed down the street and took everything away,” he breathes. In Poststraße, a usually bustling shopping street, shops, cafes and restaurants all remain closed, giving the town a ghost town feel. “All these businesses were occupied, and not all of them will reopen”, laments the guide.

Could the Ahr Valley cope?

This night of July 13, 2021, the Ahr flood reached levels never seen since the start of the records. Meteorologically, everything converged to produce an exceptional event: for several days the valley was under rain, saturating the soil. Under these conditions, even heavier precipitation was added, maintained in the region by an unfavorable weather system. In a few hours, the level of the Ahr exceeded all records. “It was really exceptional, it rained more in three days than during the whole of July”, explains Franck Kaspar, climatologist who works within the German meteorological office. In twenty-four hours, in the valley, it fell 90 liters of water per square meter whereas it receives on average only 70 liters for all the month.

Here, however, the inhabitants are used to living with the floods. “The Ahr valley is characterized by a mid-mountain range with very steep slopes, the ground is relatively shallow in most of the catchment area, so much of the descending rain runs off rapidly into the bottom of the valley”, explains Dr. Enno Nilson, of the Federal Institute of Hydrology and head of the water balance, forecasting and predictions department. But as the climate warms as a result of human-caused carbon emissions, scientists are affirmative that these kinds of extreme weather events are more intense, and more likely than before. A month after the floods, international researchers, based on statistical models, have made the link between this particular disaster and global warming: according to their work, the maximum amount of precipitation observed during this disaster was 3% 19% higher due to climate change.

Since that famous night in July 2021, questions have been running through the minds of residents. Could the Ahr valley cope with such a rising water level? A few kilometers south of Bad-Neuenahr, the small village of Altenahr was devastated by the flood. The town displays deep scars, the roads are still impassable, and two bridges have been washed away by the waves, cutting the railway line that went up the river. But it is also on the walls of a tunnel that the memory of the whims of the Ahr is inscribed. Plates testify to the level of the floods: 1888, and 1918 are superimposed on it, just like the last of 2016, and that of 1910, which is particularly high and whose plate culminates at nearly 1.5 meters above the ground. Nothing, however, foreshadowed the maximum water level reached in 2021. To find out, you have to look up high, where a line has been drawn with a spray paint, almost 6 meters above the roadway. .

Expected water retention areas

“There is no protection against a disaster of this magnitude”, observes helplessly Cornelia Weigand, the administrator at the head of the district of Ahrweiler. “It is a very rural area and there are limits to what we can do. However, the measures that we had anticipated to know how to react to a flood were based until then on the experience of past floods”, says the former mayor of Ahrweiler. The important thing now is to “define a new worst-case scenario.” To do this, the authorities should be able to rely on new projections of flood risks, taking into account the impact of climate change. “We are working to determine how far the peaks of these floods could reach in the years to come. this so that managers can adapt and include climate change in their protection plan”, specifies Enno Nilson.

How to prevent such a calamity from happening again? Tino Rossi is an architect, in front of his devastated old house, located a few meters from the river, he assures with great support of photos and graphics that such a flood could have been slowed down by dams and water retention systems. “I started talking about it in 2016, but no one listened to me”, assures the one who is also a member of the municipal council of Altenahr. “Unfortunately we know that it can start again and that it will be worse due to the climate. But we don’t want to live here anymore if there are not these protective measures.”

After last year’s disaster, residents’ demands should be heard. “It is planned to install water retention zones between the villages, which could allow us to gain half a meter during the next flood”, let know Cornelia Weigand., Before adding: “It is a start, but the flood level of July 2021 was about three times higher than in 2016, which means that more needs to be done and to find the right measures to retain water in the surrounding areas, forests , fields and slopes.”

Crossroads of issues of the time

To rebuild, there is no longer any question of making the same mistakes, warns Werner Lanzerath, the deputy mayor of Altenahr. An urban plan provides for new unbuildable zones along the river, and others force homes to be prepared for flooding, in particular by prohibiting living rooms on the ground floor. But above all, “we must think about the future. We know that we are affected by the climate and it would be unreasonable to simply rebuild without taking this question into account”, recognizes the deputy.

For some, the floods must be used to rethink the way to rebuild and to adapt to face the challenge of ecological transition. Werner Lanzerath is himself affected by the flood, since forced to live in a neighboring town, because his house was contaminated with fuel oil. This is the other problem of this isolated valley where many houses were still equipped with oil tanks for heating. The river, by flooding the dwellings, washed away these reservoirs and dispersed its pollution. Sometimes, houses are too impregnated with this toxic substance, and doomed to destruction. Thus the disaster is at the crossroads of the issues of the time: accentuated by global warming, the consequences of the flood also led to significant pollution linked to fossil fuels…

“After the water receded, a lot of houses still smelled and I think people don’t want to know about that anymore, so they ask us to switch to gas for their heating,” says Mark Kreuzberg, an entrepreneur in the region. But in the valley the crises collide. Partially rebuilt houses are waiting for materials that are running out as a result of the global crisis. Labor is scarce, construction sites number in the thousands, and with the war in Ukraine, gas is no longer synonymous with security. “Today a lot of people are hesitating and no longer know which system to choose”, observes Mark Kreuzberg. In Altenhar, the region has chosen a local heating network, and in a country aiming for the end of fossil fuels in 2035, “the gas pipelines have been laid with the idea that they are also suitable for hydrogen”, warns district administrator. A forced-march form of transition which is essential today everywhere.