Dikes won’t do: why Europe is failing to reduce flood risks

This blog was originally published on the Stockholm Environment Institute website.

Another catastrophic season of floods has arrived in Europe. Storm Boris is driving extreme rainfall and major flooding across Germany, Austria, Hungary, Slovakia, Czech Republic, and Poland. Tens of thousands of people have been evacuated as swelling of the Danube and its tributaries burst embankments. Areas of the Czech Republic have received three months’ worth of rainfall within three days. At the Polish reservoirs of Międzygórze and Stronie Ślaskie, the situation was described “out of control” as both dams begun overflowing days ago. These follow massive wildfires of last year, unprecedented heatwaves in 2022, and floods of 2021.

To researchers working with risks and climate change, such disasters are not new. They simply repeat a predictable pattern. The Intergovernmental Panel on Climate Change sums up the state of affairs and the forecast, saying, with high confidence, that climate change is increasingly contributing to extreme events in Europe, and that this will continue alongside warming of the continent.

The only surprise: the continuing lack of action and investments to reduce risk and address our awkward relationship with the environment.

Facing up to the limits of built infrastructure

Our attempts to rule nature by force are failing. Levees, dams, and engineered expansion of cities on floodplains are all manifestations of human hubris, a belief that humankind can commandeer nature. For example, levees disconnect natural floodplains, with devastating consequences on biodiversity. Dams are similarly destructive, forever changing environments.

The effectiveness of such infrastructure is decreasing. Levees can only go so high. Cities of steel and concrete cannot absorb new extremes of rainfall. Aging dams have been designed based on information of the past, rarely incorporating assessments of future flood risks. At the coasts, sea walls and concrete tetrapods are racing to keep up with the pace of coastal erosion, sea-level rise, and unsustainable coastal development. As nature reminds us with increasing frequency, waters will find a way.

On and on it goes, this cycle of unsustainable construction and maladaptive responses – newly demonstrated again and again, as the most recent floods in Europe illustrate.

Indeed, the perceived supremacy of European flood defence engineering appears to be coming to an end, and the time to reimagine futures is here, but – apart from taking the extreme approach of relocating entire cities, as is the case with Jakarta – what can be done?

Finding new approaches

Some steps are being taken. The European Floods Directive and the New European Bauhaus initiative seek to promote the protection and restoration of nature to reduce flood risks.  Nature-based solutions such as flood plain restoration and stormwater parks, have been rapidly gaining traction in planning agendas.

At the same time, the assumption that we can simply build or design away the environment is deeply engrained in the minds of planners and histories of our cities. Despite our efforts and our longstanding faith in the power of concrete, we cannot simply reintroduce nature to floodplain once it is caked with asphalt. We cannot simply re-engineer dams or re-imagine coastal zones once infrastructure is in place.

The hubris of assuming that we can force nature to do our bidding is also evident in other measures. It surfaces amidst the construction- and consumption-driven economies that cannot tackle greenhouse gas emissions because resource extraction is inherent in their design. In so many places, we confront another historical legacy that, much like our concrete cities, cannot simply be undone by taking the problem elsewhere (looking at you, carbon trades). It is also not easy to convince economies and peoples of the importance of doing things differently. Maintaining sand dunes at the coasts for flood protection may appear unappealing when the same land could be sold to hoteliers and developers at an eye-watering rate.

To mitigate risks of natural hazards in Europe – and globally – it is therefore essential that we re-examine and question the assumptions that underlie the problems we seek to tackle. Learning to live with, rather than battle against, the environment is a start. This is not only because it is necessary to confront flood risks, but also to address climate change itself.

Such an endeavour requires humility and the desire to learn. We must cultivate a healthy respect for the natures and the planet we inhabit. We must concede there will be trade-offs between economic development and safety.

The cost-benefit analysis is straightforward. If we cannot admit mistakes of the past, there is no way to negotiate the future.