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Unravelling the Vicious Cycle of Drought-Flood
In recent years, a disturbing trend has emerged, one that threatens the delicate balance of our ecosystems and poses catastrophic risks to communities worldwide. The recent flooding in Spain is a stark reminder of this reality, as we find ourselves trapped in an ever-intensifying cycle of droughts followed by devastating floods. Understanding what is driving this cycle is critical to our future. This phenomenon, deeply problematic on its own, often coincides with forest fires, compounding the devastation and contributing to further emissions.
As our planet experiences the escalating effects of climate change, the frequency and severity of extreme weather events, including droughts and floods, have surged. Rising global temperatures alter precipitation patterns, leading to prolonged dry spells and intensified rainfall when it finally arrives. This climatic upheaval disrupts the delicate equilibrium required for sustainable water management and amplifies the likelihood of drought-flood cycles.
Unfortunately, human activities have exacerbated the situation by altering natural landscapes and hindering the hydrological cycle. The concreting over of permeable ground, a consequence of urbanisation and infrastructure development, impedes the natural infiltration of rainwater into aquifers. Instead of replenishing groundwater reserves, rainfall is quickly channelled away, aggravating drought conditions by not replenishing valuable water stores. This shortsighted approach to land use has magnified the intensity and frequency of drought-flood cycles.
While Sustainable Drainage Systems (SuDS) have gained popularity as a solution to urban flooding, their effectiveness in addressing drought-flood cycles is limited.
Although SuDS provide a hierarchy of solutions, which prioritises infiltrations solutions, the infiltration options are often not seriously considered on projects, and retrospectively justified as not suitable. Design teams often just focus on managing excessive surface water runoff during heavy rainfall events, aiming to alleviate the flood aspect of the cycle. However, they often fall short in promoting groundwater replenishment. Consequently, the long-term sustainability of water resources remains compromised, perpetuating the vicious drought-flood cycle.
The impact of these events is only further exacerbated by the rush to re-build and restore following flood events that leads to a peak in embodied carbon. Often rushed flood defences are erected, redirecting the flooding issues rather than working to resolve them. It is important to understand the hydrological systems to enable the implementation of long-term solutions which address both the flood and drought aspects of the cycle.
To break free from this destructive cycle, it is beneficial to consider comprehensive groundwater monitoring. Understanding the behaviour of aquifers, tracking changes in water levels, and monitoring the quality of groundwater resources provides vital insights for effective water management. Groundwater monitoring empowers us to anticipate droughts, detect early warning signs, and implement adaptive measures to mitigate the impact of drought-flood cycles.
Chennai, India has experienced the extremes of flood and droughts for years, and is often referred to as an extreme example of where we could end up if we do not address this issue. The extremes of these floods experienced in Chennai followed by catastrophic water shortages highlight the dire consequences of neglecting water cycle management as part of city development. The warning signs are clear but need to be listened to now if we are to work to prevent future crises.
Closer to home the Netherlands has been battling with the challenges of living in a low-lying, deltaic landscape. The country's comprehensive approach to water management focuses on flood protection and water storage creating infrastructure to manage flood waters through increasing river capacities, excavating flood plains, and establishing designated areas of overflow.
In the UK, we need to learn from each other as we witness the impacts of climate change. One of the key challenges is that the systematic and long-lived causes that have brought us to this point require solutions that address the issue in a similarly comprehensive manner. Moving forward, transformative changes in design and development practices are imperative to avert the worsening of drought-flood cycles. While legislation has been introduced in the UK, and this year will mark the first time that considerations of Sustainable Drainage Systems (SuDS) become mandatory across England, with the implementation of Schedule 3 of the Flood and Water Management Act. However, this does not go far enough to address the speed at which change is occurring.
We must prioritise sustainable land use strategies that preserve permeable surfaces and facilitate the natural infiltration of rainfall. This includes preserving green spaces, incorporating porous pavements, and promoting the use of green roofs and rain gardens. In addition to implementing comprehensive water management strategies that balance the needs of urban development and ecosystem preservation is vital. This includes integrating nature-based solutions, such as tree planting and retention ponds, to optimise groundwater recharge and mitigate flood risks.
For years it has been known that we are approaching serious challenges with water shortages and yet despite efforts across the board with policy has not been sufficient and isn’t going far enough. The alarming rise in drought-flood cycles demands urgent action and a paradigm shift in our approach to water management. Climate change, coupled with misguided urban development, has propelled us into a cycle of environmental degradation and vulnerability.
Design teams need to work together to safeguard water management on projects, led by all disciples. By embracing sustainable design practices, monitoring groundwater closely, and fostering interdisciplinary collaboration, we can break free from this self-perpetuating cycle. Let us draw inspiration from successful endeavours such as those in The Netherlands, and work together to forge a resilient future, where drought-flood cycles become a thing of the past, and communities thrive in harmony with nature.