Flooding in a changing climate: rethinking infrastructure for a more resilient future

 

As part of World Water Week 2026, whose focus highlights water security, resilience and inequality reduction, flooding stands out as one of the most significant challenges facing societies today. Understanding how to assess these events and how to adapt our territories to them has become a priority for building safer and more sustainable communities.

The impacts of flooding also represent a climate justice challenge. While extreme events affect society as a whole, their consequences are particularly severe for those with fewer resources to prepare for, respond to and recover from them. According to Rentschler et al. (2022), approximately 1.81 billion people live in areas exposed to extreme flooding, and 89% of them are located in developing countries.

Exposed territories: when cities encroach on rivers

This reality is driven not only by the intensity of flooding events but also by the way societies occupy and transform the landscape. In many developing countries, limitations in urban and territorial planning have encouraged the expansion of settlements into areas naturally exposed to flooding.

These settlements are often located along riverbanks and, more specifically, within river floodplains. Floodplains play a critical role in the hydraulic dynamics of river systems and are therefore naturally activated during flood events. When occupation of these areas coincides with increasingly intense hydrometeorological events, the human, social and economic consequences of flooding can escalate dramatically.

The combination of increasing exposure of people and infrastructure in flood-prone areas, high levels of social vulnerability and the intensification of hydrometeorological phenomena calls for a fundamental rethink of how infrastructure is designed and how territories are planned. This reality highlights the need to incorporate flood risk reduction as a core component of territorial planning and development strategies.

Adapting to this new hydrological regime requires revisiting conventional design criteria. While hydraulic infrastructure has traditionally been designed using events associated with return periods of around 100 years, particularly in many developing countries, climate change is prompting a reassessment of these standards.

It is becoming increasingly common to complement traditional approaches with more severe scenarios and analyses that incorporate future climate projections, with the aim of ensuring adequate levels of safety and resilience throughout the operational life of infrastructure assets.

However, adapting to flood risk is not solely a matter of applying stricter design criteria or increasing infrastructure capacity. International experience shows that resilience also depends on understanding and harnessing the natural processes that regulate river behaviour during flood events.

Adaptation is not only about building larger protective structures. In many cases, effective solutions involve giving more space back to rivers so they can accommodate part of their natural dynamics in a controlled way.

Maintaining connectivity between a river channel and its floodplain enables temporary water storage during flood events, reducing downstream water levels and lowering risk for surrounding communities. This shift in approach is increasingly reflected in regions around the world, where adaptation strategies focus on working with natural water processes rather than relying exclusively on conventional infrastructure.

One of the most widely recognised examples of this approach is the Dutch Room for the River programme, which marked a major international paradigm shift by expanding floodplains, creating secondary channels and lowering riverbanks instead of simply raising dikes. In doing so, the programme provides more space for rivers while simultaneously enhancing flood protection and improving ecological quality.

In a world where extreme events are becoming increasingly frequent, the combination of science, planning and nature-based solutions will help reduce community vulnerability and protect critical infrastructure. The challenge is to design territories that can coexist safely, resiliently and sustainably with rivers, creating a better balance between water systems, people and the environments in which they live.