Creating resilient urban environments. By Martin Lambley

Making every drop count

Rising global temperatures are making weather patterns more extreme, and the recent summer of major droughts in the UK and across Europe raised questions of how our urban environments will cope with the effects of a rapidly changing climate. So, why is closing the water loop crucial to creating more resilient urban environments?

The summer of 2022 was clear evidence that the weather effects of climate change have arrived in the UK, and that our cities are ill-equipped to cope with extreme droughts or the flash floods that often follow. Without significant changes to our infrastructure, these events will continue to be a danger to our towns and cities.

As demand for water increases and supplies of safe drinking water are under threat around the world, urban environments will soon find their resources squeezed. It is estimated that it will take just 20 years for parts of England to begin running short of water, shifting the emphasis firmly onto making the best use of what we have at our disposal. All of this demonstrates the need to urgently start upgrading current infrastructure. Currently, these are large-scale, long-term changes that cannot be achieved overnight.

Closing the loop
Any updates to infrastructure need to include a fundamental change in our attitude towards water. The UK has long benefitted from an abundance of rainwater to the point that our drainage systems are built to quickly divert water out of our cities to prevent flooding. As water becomes scarcer and drought more frequent, we can no longer afford to be so wasteful. Drainage systems that collect, store and re-distribute water are crucial to urban environments remaining resilient in the face of ever more extreme weather patterns.

Alongside civil engineering projects that are designed to increase the capacity of ageing public drainage and water supply systems, strategies should also focus on more varied stormwater management plans, rather than simply getting it out of town. We need to champion cyclical water management systems, where rainwater can be filtered, stored, and fed back into systems for use when it’s needed most.

This was one of the challenges Wavin set for the next generation of young civil engineers and engineering students as part of the Water Futures Challenge, run in collaboration with the Institution of Civil Engineers (ICE). One of the shortlisted entries came from Naomi Betts, a civil engineering student at the University of Warwick, which answered the question: ‘How can we make use of existing rainfall?’. Her proposal suggested using vertical storage tanks for domestic roof water harvesting, an innovative solution that could relieve the strain on water supply systems by providing non-potable water during periods of drought.

Although Naomi’s idea faces several challenges before it is suitable on a wide scale, it is an example of the type of forward thinking needed to boost urban resilience into the future. As an industry, we need to look proactively at renovating and retrofitting existing buildings, as well as applying a forward-thinking approach to water on new developments.

Liveable, loveable cities
Forging a better relationship between urban environments and water is at the heart of Wavin’s vision and purpose: to build healthy, sustainable environments. A sustainable city, for example, is one that not only minimises its own impact on the climate, but also effectively manages the impact that a changing climate has on it.

Last summer was a stark reminder that we can no longer take water for granted, and that we are not prepared for the vicious cycle of drought and flash flooding that is set to continue. However, it also presents an opportunity to work collaboratively towards a circular-first mindset, that can be applied to the different disciplines, partners, technologies, designs, and solutions needed to build resilient, futureproof infrastructure. Civil engineers have their own crucial role to play in this transition, by beginning to consider the long-term impact of population growth and climate change on the projects they are working on.

Bringing more stakeholders to the table broadens the scope of possible intervention and helps to create connections between systems which have traditionally been viewed as independent. Waste-, rain- and tap water should all be integrated into larger circular water cycles that can be applied at building, neighbourhood, and city-level.

The role of manufacturers
In this context, manufacturers have a major role to play. Sustainable Drainage Systems (SuDS) are crucial in improving the resilience of new builds and renovations, with the latest technology designed to do just that in urban environments. Wavin’s AquaCell NG is an attenuation tank that is optimised for efficiency and ease of installation, making it a more viable option on projects with tight deadlines. Its lightweight and compact shape is also a great example of how the latest technology is designed specifically to address the unique challenges of urban water management.

Given the specialist nature of SuDS, manufacturers also have a responsibility to support in the installation of these types of systems. End-to-end product journeys such as Wavin’s StormForce take this one step further though, helping specifiers and developers throughout the whole process, accounting for regulations, site conditions, and co-ordinating on design and installation to ensure the optimum water management solution is delivered. Drainage cannot be an afterthought, which is where the latest technology, combined with design expertise, has a vital role to play in improving urban resilience.

With experts suggesting that British rivers could lose more than half of their water by 2050, the cost of not acting will dwarf that of building for the future. Effective action will transform our cities, ensuring we can use the water we have during drought events. Rather than saving for a rainy day, it’s the rainy days that we need to save.

Wavin North West Europe
Martin Lambley is Product Manager, Urban Climate Resilience for Wavin North West Europe. Wavin is an innovative solution provider for the building and infrastructure industry across multiple continents. Backed up by 60 plus years of expertise, it is geared up to tackle some of the world’s biggest challenges around water supply, sanitation, climate-resilient cities and building performance