How can communities advance sustainable water management?
Simon Gilliland: Going forward, to manage water supply challenges and growing risk from extreme weather events, a shift towards building resilience at the community level is required. This effort would benefit from a perspective of water-cycle management focused on achieving water neutrality—where the water footprint of every community, in terms of consumption, is offset by an ample level of availability from local water resources. Actions to support availability include effective harvesting of rainfall-generated surface water and flood water and reusing wastewater for toilet flushing, washing, irrigation and commercial applications. It is important to consider that not all water uses require treatment to drinking water standards; there is more value in surface water and wastewater than we often realise.
There will always be a requirement for initiatives to replenish existing water resources—for example, through better management of groundwater abstractions so that resources can recharge themselves, or perhaps by attenuating surface water resources to create a new source of water for local agricultural use.
These steps, and others, to build community-level resilience become even more important as the changing climate continues to alter established meteorological patterns globally, leading to rising sea levels and more extreme weather events such as heat waves and floods that can have devastating impacts on communities and natural ecosystems.
How can communities be prepared to manage the impacts of extreme weather events such as floods?
Simon Gilliland: Historically, the focus has been on building larger water infrastructure assets, such as higher flood defences and longer water transfer pipelines. However, in recent years, efforts have shifted to asset optimisation to make more efficient use of the assets we already have—through the use of smart sensors and new technologies that aid in improving existing infrastructure. This perspective has contributed to an improved understanding of surface water and groundwater availability and supports sustainable approaches to the management of surface water, groundwater and flood risks.
Digital tools, such as Floodly, are important in this process. Floodly is WSP’s flood-forecasting tool that uses machine learning methods to predict river levels and flood risk using only precipitation data. Similarly, to support water neutrality, there have also been advances in demand forecasting, leakage detection, water efficiency and re-use, enabling the more efficient management of water resources.
What role does collaboration play in meeting the universal challenge of sustainable water management?
Simon Gilliland: Global collaboration among water experts and policymakers is vital for sharing new knowledge and experiences, and there is a growing need for professionals to closely work together on a local level, engaging community members towards managing water sustainably and ensuring that the needs of all communities are met.
Water is the new net-zero challenge. However, in the necessary drive towards a net-zero-carbon future, the present-day impacts of both insufficient and excess water—droughts and floods more frequent and severe due to climate change—on communities are at risk of being side-lined.
It is important to understand that net-zero water and net-zero carbon go hand in hand; it’s not an either-or scenario.
By applying a wider perspective of water management, communities can identify and take steps to meet this net-zero water challenge and protect water resources and the natural environment overall at the same time.
Water availability is a layered issue that demands a coordinated global effort to protect water resources and ensure equitable distribution of water while adapting communities to make them more resilient to floods and other weather events intensified by climate change.
What are a few examples of net-zero water practices at work?
Simon Gilliland: WSP have been working for over a decade with Essex & Suffolk Water in the UK to help its domestic customers use water more efficiently to reduce demand, thus saving water, while reducing both their water and energy bills. We delivered a domestic retrofit programme which entailed assessing current fitments and upgrading them to water-efficient versions; at the same time, we advised regarding ways to increase awareness and encourage behavioural changes to help engagement with this initiative.
The Paddington Square development project in central London offers another example of how we analysed opportunities to not only conserve water but also to capture, treat and reuse this resource on-site. Our analysis started early in the design process as we looked for opportunities to integrate ecological water management into the design of rain, storm and wastewater systems, to ensure that potential impacts on water resources such as groundwater could be mitigated.
Our work with Affinity Water, Severn Trent Water and the Canal & River Trust, to explore how the Grand Union Canal [GUC] could provide a resilient supply of water for people and the environment, is another example of a net-zero water strategy. By reusing wastewater, a highly resilient water resource, and the GUC as a flood resilient water transfer system, the intense water supply and demand challenges in South East England can be sustainably met.
In addition to the benefits such projects bring, what broader factors will help achieve net-zero water and infrastructure solutions to protect all communities?
Simon Gilliland: As design and construction practices evolve to reduce embodied carbon to achieve net-zero-carbon goals, invariably the volume of water used will decrease. For example, in the UK a modular offsite constructed residential property typically has 10 times less embodied water than a standard onsite constructed property.2
It is also imperative that the planning process evolve. Currently, the process promotes an overly rigid interpretation of risk that limits the opportunity for much-needed innovation. For example, current national and local planning policies in the UK and globally in more developed countries typically discourage new developments in areas of high flood risk. This appears logical at face value but ultimately reduces the level of inward investment in the communities which need it most. To encourage a shift in this perspective, we are working with local authorities across the UK to unlock the potential of inward public- and private-sector investment, using FRIST, our Flood Risk Investment Summary Tool.
Climate change and the need for a water-neutral future flips established development-planning thinking on its head. Inward investment in vulnerable, at- risk communities, which often suffer from higher social deprivation, is essential so they too can adapt to the changing climate.
This adaptable, resilient mindset is epitomised by the Hadley FloodSAFE HouseTM, an approach to mitigate flood risk at property level. WSP has been working with Floodjack International and the University of Liverpool on this project that offers fresh thinking on flood resilience. Through the use of smart sensor technology, each Hadley FloodSAFE House is tailored to local conditions and is trained to recognise and elevate itself above floodwater as the floodwater rises.
Can you address the issue of cost to implement this idea?
Simon Gilliland: The beauty of Hadley FloodSAFE House is that it stacks up economically. In areas of high flood risk, land is generally less expensive than in areas of low flood risk; and the components needed to raise the house are pretty standard—such as jacks, motors, water sensors. In short, compared to traditional flood defence measures, raising homes does not have to require a major investment.
In combination, the application of the resilient FloodSafe House concept and the effective harvesting of rain and flood water—for example, through sustainable drain systems and local storage of floodwater or rooftop rainwater collection and distribution systems—presents an opportunity to form and implement water strategies that can support community needs for flood-resilient homes and a continuous supply of water.