The Environment Summer Issue 25 by Syon Media

The Environment

Proven, High Impact, Low Maintenance SuDS Turf

Wildflower SuDS Turf tried and tested in hundreds of interventions for flood resilience projects

Rapid Establishment

Pre-grown, dense roots deliver quick bank stabilisation

Verified Infiltration Rates

Tolerance for waterlogging and drought stress

Sustainable Design

100% peat-free product with no plastic netting

Stunning Visual Impact

100% flowers, long-flowering mixes for urban settings

High Ecological Impact

High biodiversity value, around 30 species per mix

Author and campaigner Hannah BourneTaylor on her fight to save the UK’s swifts

Albania’s River Vjosa was designated as a national park thanks to a campaign by the winners of the Goldman Environmental Prize 2025

Nitrous oxide emissions from wastewater treatment are a major contributor to global warming – Amanda Lake and Thomas Binninger report on some innovative mitigation technologies

Sustainable drainage schemes are an important tool in the flood risk management toolbox, but there are challenges around retrofitting them at scale, argues Kevin Barton

The team behind Resilient Roch on how the project is seeking to understand and address the barriers to climate resilience in vulnerable communities

Member news roundup

Policy commentary: CIWEM policy director Alastair Chisholm calls for a national rainwater management strategy to address both flood risk and water scarcity

CIWEM Conversations: A fellow and a graduate member share perspectives in our newest interview slot

CIWEM president Hannah Burgess shares her reflections on 22 years in flood and coastal erosion risk management

Piergiorgio Costa, a civil engineer and hydraulic modeller at Binnies, shares his route to becoming a chartered water and environmental manager

Jessica Knaggs tells us about a typical day as an environmental consultant at the engineering consultancy Arcadis

The Environment Agency’s Julie Foley talks priorities for the FCERM sector ahead of Flood & Coast 2025

Last word: Darren Eckford, CIWEM’s director of learning and organisational development on the changes we’ll see at this year’s Flood & Coast conference

of wild-living beavers to English

Katie Woollard of HR Wallingford gives the lowdown on the planned National Leakage Reduction Test Centre

Eva Bishop and Jess Chappell of Beaver Trust on the UK government’s decision to allow the return

waterways

Simon Harrow, interim director of water resources at Ofwat, on water company plans to ensure water security in England and Wales

Clean water starts with clean data.

Behind every drop of safe, reliable water lies an essential foundation: clean, accurate data. At KISTERS, we understand that data quality is crucial to achieving water quality. For over 60 years, our advanced data management solutions have empowered utilities to ensure their data is precise, reliable, and actionable. From robust data validation to sophisticated analytics, we help you transform data into a strategic asset with solutions that are designed specifically for the complexities of water management.

Let’s talk.

hydromet.sales@kisters.eu kisters.eu

CIWEM

106-109 Saffron Hill, London

EC1N 8QS

Tel: +44(0)20 7831 3110

Fax: +44(0)20 7405 4967 admin@ciwem.org www.ciwem.org

Registered Charity No: 1043409

EDITOR

Jo Caird theenvironment@ciwem.org

ADVERTISING

Lee Morris

+44 (0)203 900 0102 ciwem@syonmedia.com

PARTNERSHIPS MANAGER

Marieke Muller

+44(0)20 7269 5820 pr@ciwem.org

PUBLICATIONS MANAGER

Victoria Harris

+44(0)20 7831 3110 publications@ciwem.org

PRESIDENT Hannah Burgess president@ciwem.org

SYON MEDIA LTD

Unit 3, Boleyn Business Suite

Hever Castle Golf Club

Hever Road

Hever, Kent TN8 7NP +44(0)20 3900 0145 www.syonmedia.com

ART EDITOR

Becca Macdonald becca@syonmedia.com

Reproduction in whole or part is forbidden except with the express permission of the publisher. Data, discussion and conclusions developed by authors in this publication are not intended for use without independent substantiating investigation on the part of potential users. Opinions expressed are those of the authors and are not necessarily those of Syon Publishing, the Chartered Institution of Water and Environmental Management (CIWEM) or any servants of those organisations. No responsibility for loss suffered by any person acting or refraining from acting as a result of the material contained in this publication will be accepted by Syon Publishing, CIWEM or its associated organisations.

The Environment magazine, printed by Stephens & George on Woodforce Silk, is accredited with FSC stock certification, which certifies the timber source originates from legal and sustainable forests. The Environment magazine uses vegetable inks formulated from renewable sources and has an Aqueous seal on the cover. ISO 14001: 2004 Environmental Management.

Chartered Institution of Water and Environmental Management

Resilience and growth

AS SPEAKERS AND delegates prepare for the annual Flood & Coast conference and exhibition next month – the last at our longtime Telford home – this issue of The Environment explores some of the projects and approaches helping to mitigate the threat and harm of flooding in the UK.

We speak to Julie Foley, director of flood risk strategy and adaptation at the Environment Agency, about flood resilience and the government’s growth agenda, as well as how the upcoming consultation on the flood funding formula could help mainstream natural flood management (pp. 11-13).

Eva Bishop and Jess Chappell of Beaver Trust tell us about a species that can teach us a lot about working with nature, having been successfully managing freshwater ecosystems for the last 45 million years (pp. 16-19). We’ll soon be seeing more beavers in our landscapes, since the Westminster government announced plans earlier this year to return wild-living beavers to English waterways.

The UK will need to embrace the implementation of nature-based solutions in our urban environments too if we’re to stay resilient in the face of a changing climate. Landscape architect Kevin Barton outlines the benefits of a wide-scale rollout of sustainable drainage schemes (SuDS) while calling for an honest appraisal of the associated maintenance challenges (pp. 24-26).

But urban flood and climate resilience is about more than just top-down schemes. Some of the team behind Resilient Roch share how their project is seeking to understand and address the barriers to climate resilience in vulnerable communities (pp. 29-31).

Meanwhile, turn to CIWEM News to read policy director Alastair Chisholm’s call for a national rainwater management strategy to address both flood risk and water scarcity (pp. 40-41). You’ll also find CIWEM president Hannah Burgess sharing her reflections on her 22 years in flood and coastal erosion risk management (p. 45), and the latest instalments of our regular member profiles.

We look forward to seeing you in Telford in a couple of weeks’ time, but if you can’t be there, be sure to keep an eye on the various CIWEM social channels for updates on the action. And remember that members can access the digital version of this and past issues of The Environment (as far back as 2016) via MyCIWEM. For even more news and analysis of the sector, you can sign up to our monthly digital newsletter (which is also available to non-members) at ciwem.org/the-environment

Jo Caird Editor, The Environment theenvironment@ciwem.org

TIM FLACH

My environment: HANNAH BOURNE-TAYLOR

The author and campaigner tells Jo Caird about her fight to save the UK’s swifts, whose nesting habitat is under threat

As Hannah Bourne-Taylor tells me over video call about her new book, Nature Needs You: The Fight to Save Our Swifts, a lively scene is taking place behind her. The view is of Bourne-Taylor’s lush Oxfordshire garden, where a motley crew that includes blackbirds, house sparrows and a dunnock that she raised herself, are singing, foraging and bickering in the early spring sunshine.

It’s an apt background view for a campaigner who is so passionate about our feathered friends that on 5 November 2022, she walked naked – save for a thin

layer of body paint (see above)– from Speaker’s Corner to 10 Downing Street to launch a petition to make nesting boxes for swifts mandatory for new housing. After the petition gained 100,000 signatures, mandating swift nesting boxes was debated in the House of Commons, but the government (led by Conservative Prime Minister Riski Sunak) voted against. It was just the beginning of a tortuous – and very much still ongoing – campaign that Bourne-Taylor brings vividly to life in Nature Needs You. The book also tells the compelling stories of many other British species currently under threat.

Swifts have been dependent on cavities in buildings for their nesting habitat for thousands of years. As we renovate and demolish older properties, this habitat is lost, putting the species in grave danger. The bird was added to the UK Red List for conservation in 2021.

The solution, says Bourne-Taylor, is for new development to provide homes for swifts in the shape of so-called ‘swift bricks’: cheap, sustainable, zero maintenance bricks that provide cavity nesting habitat for swifts and other cavity nesting birds. The campaign is supported by Natural England and Wildlife and Countryside Link, which represents 88 environmental NGOs, including the RSPB.

These amazing creatures eat, drink, sleep and mate in flight, spending up to 10 months a year on the wing

No swifts are in evidence in BourneTaylor’s garden the morning of our call –partly because these visitors to the UK only begin to arrive in late April after their long journey from Africa, and partly because, when they do arrive, the only time they land is to nest. These amazing creatures eat, drink, sleep and mate in flight, spending up to 10 months a year on the wing.

Swifts are represented in our call in a sense though – sitting proudly on a shelf behind Bourne-Taylor is a swift brick. It’s the very one, in fact, that she has carried with her to countless ministerial and civil service meetings since the start of her campaign. She calls it her “comfort blanket” in her book.

WHAT’S THE LATEST ON YOUR CAMPAIGN?

Steve Reed, the environment secretary, agreed to support mandating swift bricks through a provision in the Planning and Infrastructure Bill. Primary legislation was then turned down by the Ministry of Housing, Communities and Local Government (MHCLG), but Barry Gardiner MP has since tabled a swift brick amendment. I now understand that MHCLG are considering making swift bricks a National Development Management Policy, which is brand-new and untested but carries statutory weight, so that would be a win from my point of view. The only thing that I can do now is make sure that MHCLG understand that [this measure] has

cross-party political and public support, and that they really need to do it.

HOW ARE YOU FEELING ABOUT IT ALL?

As a campaigner, it’s horrible, because in 2023, Labour whipped its MPs to support Zac Goldsmith’s swift-brick amendment to the Levelling-up Bill. The MPs haven’t been reshuffled, so it’s not like there are new people in place that don’t know anything about it. And from the swifts’ point of view, it’s two years more urgent than it was in 2023. This tiny little thing –this life raft for these birds – is wrapped up in this awful, human, political fight at the same time as being insignificant to it.

YOU WRITE IN YOUR BOOK THAT YOU “KNEW ABSOLUTELY NOTHING ABOUT POLITICS” BEFORE STARTING YOUR CAMPAIGN. WHAT DID YOU MAKE OF WHAT YOU FOUND?

Because this is a public campaign, and hundreds of thousands of people are included, it means that people from across Britain contact me all the time, and I can tell you that there is no awareness on a generalised level of the link between nature and politics, and how we as constituents can operate our MPs to serve our needs. Unfortunately, the politicians have almost no awareness of nature either, and climate and nature are completely siloed in the workings of government. We are a nation of nature lovers, so I really hope this book could be that first step for a reader to realise how ignorant they are, and if they love nature (which they will do, or they wouldn’t be reading my book), that it’s time to take some responsibility. Because few MPs are going to step up unless we make them.

HOW HAS IT BEEN TO HAVE THE UK CONSERVATION COMMUNITY BACKING

HOW DO WE ENSURE THAT NATURE AND CLIMATE DON’T LOSE OUT IN THIS GOVERNMENT’S AGENDA FOR GROWTH?

Firstly, I should say that I’m apolitical. My experience with swift bricks makes me very nervous and distrustful of this government. Because if they can’t do that which isn’t a burden on them or the taxpayer, then it begs the question, are they taking the nature recovery targets seriously? I know that Ed Miliband is a really authentic advocate for the climate, and so I feel like those initiatives are much more on track. But ironically, it’s his department that has no mitigation set up for the Great British Insulation Scheme that is destroying cavity bird nesting habitat [inadvertently, by blocking nesting sites with insulation]. So I don’t think nature is on Miliband’s agenda at all.

YOU RECOUNT BEING INSPIRED BY THE RESPONSES OF PRIMARY SCHOOL PUPILS TO YOUR CAMPAIGN – HOW CAN ENVIRONMENTALISTS HARNESS SUCH ENERGY?

Running workshops or assemblies that focus on individual campaigns is really useful, because it’s a way to empower children to help out without them feeling too anxious [about environmental challenges]. That balance is really key: you don’t want to scare the children and make them feel like they’re helpless and everything’s dying around them.

A pet peeve of mine is that a lot of primary school children know about pandas and polar bears, but they don’t know about the nature on their doorstep. Finding a way to connect them with the stuff that they can actually see and help, would be great. The new GCSE in natural

history will help so much because it will engage children with the conservation space. Having curriculum-based information about nature is really key.

WHAT CAN CIWEM MEMBERS DO TO HELP SWIFTS?

It’s very important that they acknowledge that swift bricks are not supplementary. There is a lot of misinformation around swift bricks being labelled and considered, even by the NGOs, as a sort of supplementary measure that’s a ‘nice-tohave’, along with hedgehog holes. There are clear surveys that show the benefit of hedgehog holes, but the difference is very obvious: one is supplementary and the other is critical nesting habitat. I’ve had to rebrand swift bricks to show that they are critical cavity nesting habitat for a whole category of birds that have been excluded in legislation.

Local plans involving swift bricks are great and it’s definitely better than nothing. But the non-compliance rate of local planning authorities stipulating swift bricks for developers is 75 per cent. So if planners, or anyone working within local government, took it on board to collectively tell the government, ‘This is not working; you need to mandate swift bricks’, that would be great. Having that custodianship instilled within planners and these district councillors would go a long way to success. o

Nature Needs You: The Fight to Save Our Swifts by Hannah Bourne-Taylor is published by Elliott & Thompson (£16.99)

Swift bricks are barely visible once installed

Examples of swift bricks

ACTION FOR SWIFTS ACTION FOR SWIFTS

BIG PICTURE

THE RIVER VJOSA travels 269 km from the Pindus mountains of Greece to Albania’s Adriatic coast. With the Balkans remaining largely untouched by industrial development during decades of civil war, the Vjosa is undammed within Albania, making it a haven for biodiversity, including critically endangered European eels, endangered Egyptian vultures and otters. It now has a good chance of staying that way, thanks to Besjana Guri and Olsi Nika, who in April were awarded the Goldman Environmental Prize 2025 for their campaign to have the river and its tributaries designated as a national park. The details are still being worked out, but commercial activity will be prohibited in 75 per cent of the park, with traditional grazing permitted in the remaining 25 per cent, and the Albanian government is working with Greece to make it transboundary so the river is protected along its full length.

Photo © Goldman Environmental Prize

PIPE DREAMS

The National Leakage Research and Test Centre will accelerate novel solutions to reduce leaks in the water sector, explains Katie Woollard M.CIWEM

C.WEM, a project manager at HR Wallingford

Water leakage is a huge problem in the UK as a result of our aging infrastructure, with 20 per cent of total water currently lost from distribution networks. Climate change is going to result in more severe and frequent droughts, causing more pipes to crack and adding to the risk of future water scarcity.

There’s a government target to reduce leakage by 50 per cent by 2050, and reducing leakage is key to water companies’ water resource management plans. Yet broken pipes are difficult and expensive to detect and mend.

A lot of good planning work has gone on collaboratively across the water companies in this space. Now the sector needs to come together to make it happen. The National Leakage Research and Test Centre (NLRTC) is part of that, enabling the innovation needed to make our water network resilient.

The centre, a partnership between HR Wallingford and Northumbrian Water, with support from WRc, will consist of an offline district metered area (DMA) – a

section of water supply network not connected to any homes or businesses – and a smaller test rig, known as a sandpit. The DMA will be a 5km-long buried pipeline under fields adjacent to HR Wallingford’s base at Howbery Park, Oxfordshire, with the sandpit occupying our existing research facility, the Froude Modelling Hall.

Reducing leakage is key to water resource management plans

It’s very challenging to test on a live network, so the DMA will replicate a real underground water network, including water treatment works, pumps, different types of pipe material, leakage simulation bunkers and a control room for automated control. It will enable us to understand more about the sorts of technologies that innovators might want to explore, with no risk of obstructing supply to customers.

Universities at the moment are developing ‘pipe bots’, for example –little robots with ultrasonic acoustic

sensors which listen for holes in the pipes and check for pipe thickness. Some pipe bots might just report back to the operator via wi-fi, while others might one day be able to coat the inside of a broken pipe with resin, thereby avoiding the need to dig it up for repair.

The centre will be able to certify technologies for application in the water industry, which should speed up bringing new technologies to market. Removing the need for each water company to carry out its own certification procedure will also reduce duplication and cost.

The sandpit, meanwhile, will be for earlier stage development, before innovators are ready to test their technology on the DMA.

The centre is financed for the first three years with a £5.3 million grant from the Ofwat Innovation Fund, plus £600,000 from water companies and research institutes. Water companies are able to sign up to a sort of subscription which will grant them access to the site for a certain number of days per year. Other users – academics, other water companies, private sector innovators – will be able to pay as they go.

We have consulted with water companies, universities and supply chain innovators – everyone that might come and use the centre – about the facilities, location, design and specification, as well as what sorts of technologies we’ll be able to test here. As a result, the centre is completely unique in its scale and its flexibility – the sort of safe environment for innovators that doesn’t exist anywhere else in the world. And because it’s a collaborative environment, with water companies on the project’s advisory board, it will be able to respond to new needs as they appear. If there was a particular innovation coming through, we could designate an area for it.

We’ll be submitting a planning application soon and anticipate that construction will start later this year. Cutting leakage by 50 per cent over the next 25 years is a challenging target so this is a really positive story. o

Members involved in leakage reduction might be interested in the work of CIWEM’s Water Supply and Quality Specialist Panel. To learn more, and to join, visit ciwem.org/communities

The NLRTC’s DMA is planned for the two fields at the top of this view of the Howbery Park site

LEADING VOICES: JULIE FOLEY

With Flood & Coast 2025 just around the corner, Jo Caird talks to the Environment Agency’s director of flood risk strategy and adaptation about flood resilience and the growth agenda

When we talk about flood resilience, we’re talking about an issue that’s really pertinent for the whole of the economy,” says Julie Foley, director of flood risk strategy and adaptation at the Environment Agency (EA). It’s exactly two months until the start of Flood & Coast 2025 and Foley is

talking to The Environment over video call about the role of flood resilience in the government’s growth agenda. It’s a key theme at this year’s conference, as the wide and varied flood and coastal erosion risk management (FCERM) sector grapples with how best to position FCERM as an enabler of sustainable growth going forwards.

With the government due to announce the outcome of the 2025 Spending Review on 11 June, the timing of this year’s Flood & Coast, while purely coincidental, feels very apposite. The discussions that will take place in Telford on 3-5 June will hopefully leave the sector in a good place when it comes to responding to the new funding landscape from 2026 onwards.

The timing makes life somewhat tricky for your humble correspondent, however, as the leadup to the conclusion of a spending review is a less than ideal time to interview a senior official from an

arms-length public body. While not a civil servant herself, Foley is bound by rules similar to those that apply to civil servants and therefore isn’t allowed to comment publicly on an ongoing spending review.

CRITICAL INFRASTRUCTURE

What Foley can talk about are her team’s investment priorities and how they align with the government’s ambition of turning around the UK economy. Citing the recent update to the EA’s National Flood Risk Assessment (NaFRA), a planning tool which provides evidence of current and future flood risk from rivers, the sea and surface water for England, Foley points out that “about a third of all roads and railways are in places of flood risk and about 13 per cent of agricultural land across England is at flood risk”.

She goes on: “When we’re thinking about how we contribute to the wider government agenda of growth, flood resilience is absolutely fundamental because we obviously need to make sure that all of the critical infrastructure, which is going to be so vitally important, is as flood resilient as possible.”

A third of all roads and railways are in places of flood risk

There’s a value-for-money argument in favour of flood risk investment too, Foley says, because of the enormous costs associated with damage to homes, businesses and infrastructure from flooding events.

“One of the things I regularly cite in my conversations with the government, the financial sector and other partners, is that for every pound that we invest in flood defences, it avoids £8 of damages, and of that £8, around £3 are direct savings to the exchequer because around a third of the damages that come from floods comes from damages to publicly-owned infrastructure: road, rail, schools, hospitals. It makes a really compelling case when it comes to thinking about flood investment.”

FLOOD FUNDING FORMULA

We will have to wait until 11 June to find out how much the EA will be given to invest, but when it comes to the particulars of how the agency’s money is allocated to flood risk management,

changes are afoot beyond those heralded by the Spending Review. In November 2024, the government first announced that it will be consulting on the ‘flood funding formula’, the method the EA uses to calculate which proposed FCERM projects should be funded and to what extent. The environment secretary, Steve Reed, repeated this pledge in February but hasn’t yet specified when the consultation will take place, only that “it will be launched in the coming months”.

“The direction of travel is really welcome”, says Foley, “because going forward we need to encourage a wider portfolio of flood projects.” Because of the way it allocates funding based on the number of properties protected, the current funding formula has tended to support traditional flood defences – dams, sea walls and reservoirs, for example. This has been at the expense of nature-based solutions for flood management – such as wetland creation or flood plain restoration – which are more likely to be implemented in sparely populated areas; maintenance of existing assets; and property flood resilience measures that people can take in their own homes.

“We’ll definitely need more of those hard, engineered defences, but because [the formula] is really out-of-date now, there have been quite a lot of barriers to enabling us to fund those other wider resilience measures,” says Foley.

“It’s just recognising – and the Environment Agency has said this for years – that we can’t build our way out of future climate risks, and so it’s important that we think about other ways to support communities.”

NATURAL FLOOD MANAGEMENT

Nature-based solutions (the multiple, cross-sectoral benefits of which we cover often enough in these pages that there’s no need to outline them again here) should not only receive a bigger slice of the funding pie, says Foley, “but we want to look at how we can do it more at scale and across all locations, and also work with other partners, like the NGO sector”.

She points to the EA’s £25 million Natural Flood Management Programme (NFMP), which is funding 38 flood resilience projects across England through March 2027. The programme was shaped by the Working with Natural

CURRICULUM VITAE

JULIE FOLEY IS director of flood risk strategy and adaptation at the Environment Agency (EA), a role she has held since 2019. Her previous roles at the agency, which she first joined in 2006, include area director for Kent, South London and East Sussex, and senior leader on the 10-year review of the Thames Estuary 2100 tidal flood risk plan (see the Autumn 2024 issue of The Environment). Foley is also the EA’s executive champion for race equality, diversity and inclusion. In the New Years Honours 2022 she was awarded an OBE for services to flood risk management.

Processes Evidence Directory (the first update to which was published in February), testing the EA’s approaches to future investment and delivery.

“Flood projects tend to be led by either the Environment Agency or a local authority or internal drainage board –the more usual suspects in flood risk management, often in partnership with many partners,” Foley explains.

There have been a lot of barriers to funding wider resilience measures

“But what we’re seeing [with the NFMP] is that some of the most inventive and creative natural flood management projects are being led by NGOs. It’s showing us that they’re great partners in building collaboration with landowners, farmers, local communities, and building trust, but also being able to lever in other sources of funding.”

Accessing the funding for implementing natural flood management at scale and

across more of the country is hopefully about to get a bit easier, thanks to what Foley sees as a shift in mindset towards nature-based solutions among diverse stakeholders including local authorities, the Bank of England, mortgage lenders and the insurance sector.

“They’re all much more enlightened about natural flood management, saying that it should be an option first, more than a last resort,” says Foley. “Those kind of conversations are really quite mainstreamed now and quite mature, so I have a lot of optimism that, in terms of market readiness to be able to scale up to do more nature-based solutions, yes, there’s a huge market appetite for it.”

Some of the most inventive and creative natural flood management projects are being led by NGOs

Part of the reason for this change of mindset is a growing awareness of “flood risk [as] one of the biggest societal risks”. Hearing that view elucidated in a recent meeting with UK Finance, the trade association for the UK banking and financial services sector, was “definitely a sit up and take notice moment” for Foley.

She explains: “Their drivers are not flood risk outcomes in the way that the EA’s would be. What they’re seeing are the risks that people won’t necessarily be able to get affordable mortgages or flood insurance unless we mitigate the flood risk in the first place, using more preventative measures.”

PROPERTY FLOOD RESILIENCE

Which ties in nicely with another strand of Foley’s work: property flood resilience (PFR). In January her team commissioned an independent review of PFR measures from Professor Peter Bonfield at the University of Westminster, bringing together the EA, financial bodies, mortgage lenders, the insurance sector and home building organisations to have a “conversation about how they can help to create a market for property flood resilience and to mature that market”. It’s a follow up to an action plan published in 2016 that set out recommendations from the Property Level Flood Resilience Roundtable, which Bonfield chaired. That 2016 action plan was strongly aligned with parallel activities CIWEM

OUT OF OFFICE

WHAT IS YOUR EARLIEST ENVIRONMENTAL MEMORY?

The Great Storm of October 1987. I was at primary school in North London and recall walking out with my dad the morning after and being shocked to see fallen trees across roads and many damaged shops and buildings. It was my first experience of a natural hazard and the power that storms can have on peoples’ lives and livelihoods.

WHAT IS YOUR FAVOURITE PLACE IN NATURE?

As well as being one of the biggest flood storage areas in the country, the

was undertaking to support PFR. This has evolved into the initiatives CIWEM is now developing around PFR (see ‘Ready or not’, pp. 29-31).

“We’ve done a lot of work in recent years to pilot options, test products, raise their credibility within the market,” says Foley. “But there’s only so far that we can go as the EA if we want to be able to mainstream it into something that house builders are considering in a much more mainstream way, trains people and gives advice to the likes of you and me.”

Key to the review will be engaging the sorts of stakeholders who are “not the people who would turn up at Flood & Coast”, she adds with a smile.

Ouse Washes is home to some of the country’s most precious bird life. A wonderful place is the WWT Welney Wetland Centre where you can spend some truly tranquil and mindful time observing the wildlife.

WHAT ARE YOU WATCHING?

I love Aardman – the creators behind Wallace and Gromit – and so I was thrilled when some of the projects involved in our Flood and Coastal Resilience Innovation Programme had an opportunity to collaborate with Aardman on Darcy’s Tale, a short animation about groundwater flood risk.

THE TIME IS NOW

For those of us who will be heading to Telford in June, the sense of urgency –around the rollout of not just PFR but all the tools in the FCERM toolbox – is acute.

With the latest update to the National Flood Risk Assessment finding that 6.3 million properties in England are in areas at risk of flooding, increasing to 8m by mid-century according to current climate change predictions, there’s no time to lose.

“Flood and climate adaptation isn’t just a tomorrow issue,” says Foley. “It’s already a today issue in a very significant way.” o

Learn about our FCERM Specialist Panel at ciwem.org/communities

© STEPHANIE FOOTE / WWT

WWT Welney Wetland Centre, Norfolk

STANTEC: DRIVING RESILIENCE IN COMMUNITIES AND THE ENVIRONMENT

As the UK water industry rolls out the largest infrastructure investment programme in its history, the energy sector carries out the great grid upgrade, and developers and local authorities press on with delivering new communities and 1.5 million new homes – efficiency, deliverability and resilience are top of mind for everyone involved.

The scale of the resilience challenges that the UK is facing is enormous, and the urgency for solutions is especially noticeable in coastal areas – places where space is becoming increasingly constrained, and climate impacts can be particularly pronounced.

LOCAL KNOWLEDGE PAIRED WITH GLOBAL BEST PRACTICE

With a reach that spans the entire built environment, Stantec, a leading global provider of sustainable design and engineering services, is once again

exhibiting at this year’s Flood & Coast event.

Quickly growing in the UK and Ireland, the company now has around 4,000 passionate professionals operating from more than 30 locations. Our teams are embedded across the FCERM, water, transport, community development, buildings and energy sectors. From planners, designers and ecologists, to designers, hydrologists, modellers, economists and engineers, we have extensive experience in funding, planning, development, appraisal, design and delivery of complex resilience schemes.

At Flood and Coast 2025 we’ll be highlighting our work supporting communities across the country and around the world in overcoming their environmental and development challenges – particularly around flooding and coastal erosion. Areas where we harness industry-leading solutions,

innovative technology and creative thinking to bring transformative results.

We’ll also be hosting our third resilience roundtable event for delegates. This year’s panel discussion will focus on shared experiences across the FCERM and water sectors and is open to anyone looking for valuable, tangible insights.

We believe the commonalities across these areas are important for several reasons. Designing for riverine and coastal environments has obvious challenges from an engineering

perspective but there are also numerous overlaps in terms of consenting, managing risk, environmental sensitivities and the potential for environmental improvements.

The need for development and new infrastructure has never been greater, but at the same time a balance needs to be achieved when it comes to safeguarding our natural environment.

ENVIRONMENTAL RESPONSIBILITY

At Stantec, we recognise every project we take on has the potential to positively impact nature and the environment, as well as safeguard the future of communities. When we embed naturebased solutions (NbS) into our designs, we help protect and restore ecosystems while enhancing climate resilience and creating lasting benefits for people.

Addressing the impacts of climate change is at the heart of our purposedriven growth strategy, and more than 62 per cent of our revenue comes from work supporting the core United Nations Sustainable Development Goals.

Coastal areas are often the first to experience the impacts of climate change, while also having rich ecosystems and habitats. Suffolk’s Benacre and Kessingland shorelines are no exception, facing erosion and the risk of inundation by coastal flooding. These issues threaten homes, businesses, farmland and infrastructure like the A12 main road. We delivered detailed design for flood risk management and intertidal habitat creation. New embankments, a major new pump station and the creation of intertidal areas will enhance coastal flood defence and biodiversity, provide social value and support the resiliency of the catchment.

A HOLISTIC APPROACH

We believe it’s essential that we take on a wider view of catchments and understand how each choice made in one sector impacts other areas and the local natural environment. Our work with local authorities, the Environment Agency, water companies, landowners and developers helps us promote genuine catchment-based thinking that includes water use and FCERM at a policy level.

Further inland, Stantec worked with local authorities, agencies and utilities in Greater Manchester to develop a collaborative and sustainable integrated water management plan. The plan incorporates strategies like blue-green infrastructure, water landscape

restoration and biodiversity as future components of watershed improvements.

MAKING THE MOST OF NATURE

One in six houses across the UK is currently at risk of flooding. When it comes to flood protection, we are continually pioneering more sustainable solutions. We know that nature is one of the best defences against flooding in a changing climate, and we recently created a report for insurer RSA and the Wildlife Trusts, examining the multiple benefits of natural flood management (NFM).

The new research, which gained national media coverage, looked at 10 NFM schemes created by individual Wildlife Trusts. Collectively, they had an average total cost-benefit ratio of 4:1 over 10 years rising to 10:1 over 30 years. By helping quantify the value of working with natural processes, including for flood risk mitigation, we can build a better knowledge base to see the benefits for nature, society and climate.

INSIGHT-LED CONVERSATIONS

So, how can stakeholders across the built environment work together, share best practice and deliver effective solutions that address resilience for communities and the environment at scale. Sharing knowledge is an integral part of success. Our 2025 panel talk at Flood & Coast follows two prior successful events. In 2023, we examined viability issues around nature-based solutions in coastal areas, drawing on our global experience in North America and work in the UK.

Last year’s resilience roundtable looked at the benefits of integrated approaches to flood management and coastal resilience. We brought together a group made up of representatives from local authorities, water companies and

contractors to discuss best practice when it comes to integrated programmes. We spoke around our experience in the Northumbrian Integrated Drainage Partnership (NIDP), which brings together water companies, local authorities and the Environment Agency to take an integrated approach to regional flood risks.

Discussions like these which transcend sectors and individual responsibilities are important in breaking down perceived siloes. By learning from what’s worked, and what hasn’t, we can help drive meaningful innovation and redefine what’s possible for resilience in communities. o

Find out more about Stantec and our holistic range of interdisciplinary services at www.stantec.com

JOIN US AT FLOOD & COAST WHERE WE’LL BE TALKING ABOUT OUR INVOLVEMENT IN THESE PARTNERSHIPS AND PROJECTS VIA A PANEL TALK. WE’LL ALSO BE ON STAND E38

Key services

o Flood mitigation and river basin management

o Nature-based solutions

o Reservoirs, dams and levees

o Pump stations and control structures

o Navigation structures

o Water resources and supply

o Wastewater recycling and water management

o Bathing waters and water quality

o Coastal storm risk management

o Ecosystem restoration/living shores

o Blue carbon

o Offshore renewables

o Ports and harbours

o Stormwater and urban drainage

BEAVERING AWAY

Beavers can create wetlands that serve as vital wildlife refuges during extreme heat and wildfires

Beavers will only make a dam if a watercourse isn't deep enough for their needs

A thriving wetland in Bamff, Canada

Beavers can fell trees with trunks up to 1 metre in diameter

IA freshwater ally returns to England to boost climate adaptation, report Eva Bishop, head of communications and education at Beaver Trust, and the charity's policy lead, Jess Chappell

n February this year the Westminster government announced its plans to return wild-living beavers to English waterways. Until now, beavers could only be released into secure enclosures, so the announcement signifies a step change: the government will now be looking to work with stakeholders on a vision and plan for managing their recovery in England.

Beavers have also been elevated to the Environment Agency’s (EA) toolkit as a recognised national flood defence measure. This year for the first time, thanks to a sufficient evidence base, the EA’s Working with Natural Processes Evidence Directory, a guide to natural flood management (NFM), includes beavers among 17 recommended measures that can protect, restore and emulate the natural functions of rivers, floodplains and the coast to reduce flooding and coastal erosion.

NATURE’S ENGINEERS

Freshwater ecosystems have been modified and managed by this native rodent since the Eocene period (around 45 million years ago). Beavers once held a keystone role in our natural history and therefore warrant a place in our landscapes, especially having been hunted to extinction here at the hand of humans.

But it is their habitat modification – their ecosystem engineering – that most interests people and has generated such phenomenal support. There is increasing evidence gathered from beaver wetlands that demonstrates the potential for beavers in our landscapes: to help reinstate resilience along many riverscapes, as well as redressing the imbalance brought about through land modification and management practices in recent decades. Every night, beavers will be out manipulating their environment – the effects are impressive, including the creation of leaky dams, ponds and coppicing. They re-establish complexity in the riparian zone (or river edges) and it is complexity that builds resilience.

The animals will only build dams where water levels are insufficient for their safety: they aim for around a metre in depth to ensure protection from predators and a submerged entrance to their lodge. Beaver presence is therefore going to be more keenly felt in uplands or headwater streams where they can transform a shallow trickle of a stream into areas of more pooled, deep water. Whereas in deeper, wider rivers, they won’t build dams and their presence can go unnoticed for months if not years.

Freshwater ecosystems have been modified and managed by beavers for 45 million years

Beaver territories will often contain a series of dams and linked canals. In doing so, beavers expand the wetland area, which aids in their movement as they’re far more efficient in water. Beaver dams are impressively robust structures made of sticks, stones, mud, logs and any other building material to hand. As water slows and pools behind the dam, sediment drops out and forms a gentle slope, beyond which there is a steeper drop down to the stream below. The dams provide water filtration and can be impressive to behold. Crucially, they are also maintained and repaired over time by the beaver family, sustainably managing the wetlands that surround them. And they do this for free.

NATURAL FLOOD MANAGERS

As a nature-based solution (NbS) to our increasing flood extremes, the beaver is hard to beat. Beaver sites can reduce flows during flood peaks by up to 60 per cent, even during heavy storms and in wet conditions. While this won’t happen everywhere and is not going to solve all flooding problems, it is a welcome opportunity for low-cost resilience building.

Better still, the reverse is also true: the ‘slow, spread and store’ effect of beaver damming activity leads to groundwater recharge, and has been shown to help

mitigate drought by maintaining water in the landscape when adjacent fields are dry. A useful outcome not only for the wildlife that relies on freshwater, but also for activities such as livestock farming which require pasture irrigation and green fields.

As well as drought, the permanence of rewetted watercourses and adjacent land can build vital refuge from extreme heat and wildfire. Over in California, where the European beaver’s close cousin, the North American beaver, resides, research by Dr Emily Fairfax has shown riparian zones with beaver activity were three times less affected by wildfires compared to the riparian zone without beaver activity. Extreme heat is in all our futures – giving space to wetlands created by beavers can help provide a refuge for wildlife and ourselves.

It isn’t just the rural landscape that can benefit from water storage. In a busy region of west London, beavers can be found nestled in an urban nature reserve with high footfall, where they were parachuted in (not literally) to help with an urban flooding and water quality initiative. The Ealing Beaver Project is a flagship community scheme, partnered by the local authority, which continues to receive significant interest both locally and nationally as a demonstration of NbS in an urban context.

By mid-century, the UK government estimates that one in four properties will be at risk of flooding. In this climate reality, we need to work with nature for sustainable water management.

CLEANING UP OUR ACT

Water quality is an issue that has been in the spotlight more than almost any other in recent years, one that is increasingly challenging for many British rivers. There is growing demand for sustainable solutions and, once again, beavers can offer a helping hand. Their dams act as sieves, filtering the water moving downstream, sometimes leaving it visibly clearer as it leaves the wetland.

In addition, valuable research from the University of Stirling published earlier

A BRIEF HISTORY OF BEAVERS IN EUROPE

this year revealed the extent to which beaver wetlands have a role to play in improving water safety. In their study, researchers found significant decreases in microbial pollution downstream of the beaver dams within an agricultural landscape: a staggering 95 per cent reduction in peak concentrations of E coli, which can cause illness.

ZOOMING OUT

If all this isn’t compelling enough, the real magic starts to happen at landscape scale, when beavers are given space to affect the shape and reach of the river itself. Over time, beaver damming activity has been shown to reconnect a deep river channel with its floodplain – restoring the exchange of water between channel and surrounding land where it had carved a deep trench over time (see box, facing page).

Clearly with such a dynamic and impactful species returning to an intensively-controlled landscape, there will be challenges and a period of transition on the way to our peaceful coexistence with beavers. Holding more water in the landscape will not always be received as positive, depending on the existing land use. It is in effect creating localised flooding. So in some instances, where this may be undesirable, this will mean a need for interventions, most of which must be done under licence.

As a nature-based solution to our increasing flood extremes, the beaver is hard to beat

At Bridge Creek, Oregon, beaver dam analogues – basic timber structures to slow the flow of water – were built by a team in a wide, deep and relatively dry river bed, successfully mimicking the natural processes of beaver dams in holding back water and sediment. Beavers then moved in to continue this work, adding further dams, which built the river bed back up by slowing water flow, trapping sediment and encouraging vegetation growth. Over time this process eventually reconnected the stream to its adjacent floodplain, rewetting the land around the channel and restoring a heavily degraded ecosystem. This floodplain reconnection could prove a low-cost strategic measure towards river restoration at catchment scale.

An established hierarchy of beaver management actions ranges from the very basic – protecting trees with tree guards – to more involved measures such as flow and dam height management. Where there is no alternative, beavers can also be trapped and removed.

SCALING-UP EFFORTS

True adaptation to future climate scenarios will require fairly radical change. We can no longer afford to rely on an approach which focuses on reactive responses to flood events, rather than preventing flooding in the first place. Under the Climate Change Act 2008, the UK is legally required to adapt to climate change. The third National Adaptation Programme (NAP3), published in July 2023, sets out actions that the government will take over the next five

Beavers almost extinct across

Protected

Beavers lived across most of Europe and northern Asia

Last record of a beaver in Scotland

Reintroduction of beavers in Europe, starting with Sweden

River Otter Beaver Trial, England

Protected status for England’s beavers

years ago

Beavers engage in mutual grooming to remove debris from their fur and waterproof it with oil from anal glands

a) Beavers will

a) Beavers will dam streams within narrow incision trenches during low flows, but stream power is often too high, which results in blowouts or end cuts that...

How B Resto

How B Rest

How Beaver Damming can Restore Incised Streams

How B Rest

How Res

How B Resto

THE EVOLUTION OF A BEAVER DAM

incision trenches during low flows, but stream power is often too high, which results in blowouts or end cuts that...

a) Beavers will dam streams within narrow incision trenches during low flows, but stream power is often too high, which results in blowouts or end cuts that...

d) Because streams that have recently incised often have high sediment loads, the beaver ponds rapidly fill up with sediment and are temporarily abandoned, but the accumulated sediment provides good establishment sites for riparian vegetation. This process repeats itself until...

A. Beavers will dam streams within narrow incision trenches during low flows, but stream power is often too high, which results in blowouts or end cuts that...

B. ...help widen the incision, which allows an inset floodplain to form.

a) Beavers will dam streams within narrow incision trenches during low flows, but stream power is often too high, which results in blowouts or end cuts that... power, which enables beaver to build wider, more stable

Source: Using Beaver Dams to Restore Incised Stream Ecosystems (Pollock et al, 2014)

Using

D. Because streams that have recently incised often have high sediment loads, the beaver ponds rapidly fill up with sediment and are temporarily abandoned. The accumulated sediment, howver, provides good establishment sites for riparian vegetation. This process repeats until...

Source: Using Beaver Dams to Restore Incised Stream Ecosystems (Pollock et al, 2014)

Source: Using Beaver Dams to Restore Incised Stream Ecosystems (Pollock et

years. These actions include investment in the natural environment. By creating more flood-resilient catchments and naturalised landscapes, we can help reduce the likelihood of severe impacts from flooding and the escalating cost of repairs. There is a role for beavers in helping to deliver this.

Beaver restoration is at differing stages across Scotland, Wales and England. Scotland has led a full strategy for beavers’ return through to 2045, strategically assessing potential catchments. Whereas in Wales, late last year, the government announced its support to move towards managed reintroductions of the species. It has recently consulted on legal changes for their protection.

In England, following February’s announcement to allow releases into the wild, the initial window for applicants’ expressions of interest to release beavers closed on 2 May. It is important that Natural England now prioritise the

B. ...the beaver dams raise the water table sufficiently to reconnect the stream to its former floodplain.

issuing of release licences to all viable applicants such that proactive progress is made toward the restoration of this species beyond enclosures. Only by doing so will we maintain momentum toward their successful return across the country.

THRIVING WATERWAYS

If we are to realise the benefits of beavers and help restore balance to our freshwater ecosystems, two things are needed. Firstly, beaver population numbers will need to be significantly higher than they are at present – there are around 2,500 animals currently in Britain, but our European neighbours have populations in their tens and hundreds of thousands.

But we also need to give beavers more space to operate in the riparian zone by adequately incentivising space for nature along rivers. This will also create space for water storage (effectively intentional flooding) in the landscape which is a fundamental step toward climate

vegetation and sediment fill the ponds, and the stream ecosystem develops

C. The widened incision trench results in lower stream power, which enables beavers to build wider, more stable dams.

C. Eventually, vegetation and sediment fill the ponds, slowing the flow of water and raising groundwater levels such that multiple channels are formed. These are often connected to off-channel wetlands, ultimately saturating the entire valley.

adaptation. Naturally functioning river systems could then become nature-rich corridors, benefitting people and wildlife. At Beaver Trust our vision is for thriving waterways vibrant with life, where beavers are embraced as a vital part of the landscape. We want people out walking to be able to enjoy spotting the signs of beavers – the classic pencilshaped tree stump or ‘beaver chips’ in riverside woodland. We want to see the species reabsorbed into our cultural mindset, to have it protected and valued. Britain is generationally behind much of the rest of Europe, where beaver populations are greater and coexistence has become the norm. The question now is whether we are willing to change and adapt in order to live alongside them and reap the balance and benefits they provide. o

Engage further on land management via CIWEM's Natural Capital Specialist Panel. Visit ciwem.org/communities

Source: Using Beaver Dams to Restore Incised Stream Ecosystems (Pollock et al, 2014)

Source:

Beaver Dams to Restore Incised Stream Ecosystems (Pollock et al, 2014)

NO LAUGHING MATTER

TNitrous oxide emissions are a major contributor to global warming. Amanda Lake, a specialist in wastewater treatment and resource recovery at Jacobs, and Thomas Binninger, a sales manager at CTP Air Pollution Control, report on innovative mitigation technologies

ackling nitrous oxide – possibly better known to readers as ‘laughing gas’ – has for the first time been included in the business plans of English and Welsh water companies. In AMP8, the asset management plan for water companies that began this past April, more than £300 million of funding has been allocated to reduce emissions of this potent greenhouse gas from wastewater treatment. Yet with many of the proposed mitigation solutions yet to be demonstrated, the next five years are set to be an exciting time to be working in water sector decarbonisation.

Nitrous oxide (N2O) and methane (CH4)

are potent greenhouse gases produced and emitted during wastewater treatment as ‘process emissions’. Nitrous oxide, in fact, has 273 times the global warming potential of carbon dioxide. Globally, the waste sector (including wastewater) is the third largest anthropogenic methane emitter, and wastewater is the sixth largest source of anthropogenic nitrous oxide. Nitrous oxide and menthane emissions now comprise the most significant proportion of greenhouse gases (GHG) from most wastewater treatment plants (WWTPs), particularly as electricityrelated ‘Scope 2’ (or indirect) GHG emissions are becoming decarbonised.

In recent years, the global effort to measure and reduce process emissions from wastewater treatment has unveiled significant challenges and costs.

Methane presents an easier opportunity now. As well as being a potent GHG, methane leaks are a health and safety risk, and a source of lost revenue, because of the gas’s usefulness as a source of biogas. Water companies are therefore beginning to recognise the importance and economic viability of finding and fixing their main sources of methane emissions, which are leaks from biogas and biomethane infrastructure. Mitigating nitrous oxide is a different

Nitrous oxide is a potent greenhouse gas produced and emitted during wastewater treatment as ‘process emissions’

story. Despite the urgency in climate terms, full-scale, sustained nitrous oxide mitigation remains largely unexplored, with few case studies to guide the way. Examples relevant to wastewater utilities remain limited, which makes developing meaningful baselines, reduction targets and viable business cases very difficult. Here, we discuss how nitrous oxide reduction at WWTPs should be prioritised via different approaches – what we term an abatement hierarchy – and the potential role for nitrous oxide destruction within this.

NITROUS OXIDE PRODUCTION

Nitrous oxide is produced during the biological treatment of wastewater. The micro-organisms or ‘biological infrastructure’ in our WWTPs generate nitrous oxide via multiple recognised pathways in different parts of the plants. Nitrogen – the root source of nitrous oxide – gets into our wastewater as a result of food processing, from soaps and detergents, and from industrial and agricultural sources. The majority, however, is excreted by people as urea in

our urine, having come into our bodies in the first place through our consumption of protein (which for most of us is higher than dietary guidelines recommend). When urine enters the sewer system, the urea converts to ammonium. At the treatment plant, this ammonium is the starting point for microbial processes that convert nitrogen compounds into less harmful forms than ammonium – but under certain conditions, these processes can lead to the production and release of nitrous oxide instead. Whilst nitrous oxide can also be removed in WWTPs, it is typical that more nitrous oxide is produced than removed – and production can be greater when the microbial populations at a WWTP are under stress (such as high loading rates or insufficient ‘food’ or oxygen). Under these conditions, the biological pathways that normally convert nitrogen compounds to harmless nitrogen gas (N₂) may be partially completed – leading to the accumulation and release of nitrous oxide.

When it comes to mitigating emissions of nitrous oxide from WWTPs, continuous, long-term measurement is a crucial first step. As utilities around the world start understanding and mitigating their nitrous oxide emissions, the sector is learning that there is a lot of variability within and across WWTPs. Levels of nitrous oxide emissions depend on the type of WWTP process as well as operational conditions such as levels of biomass loading, dissolved oxygen and available carbon (carbon may be required to ‘feed’ the microbial population where total nitrogen reduction is needed). Nitrous oxide production and emissions also show significant seasonal variations.

REDUCING NITROUS OXIDE EMISSIONS

Despite our incomplete understanding of the full nitrogen cycle and nitrous oxide production and emission mechanisms, there are several viable mitigation strategies already in use in the wastewater treatment sector (see box, p. 22). The preferred strategy is avoiding nitrogen in the first place; followed by reducing the production of nitrous oxide; then, for residual emissions which cannot be avoided or reduced, removing the nitrous oxide which has been produced.

Nitrogen can be avoided through upstream interventions such as urine source separation in new development.

It can be avoided within WWTPs too, by recovering nitrogen from sidestream processes (treatment units that handle specific high-strength waste streams separately from the main flow, and which have been linked to very high nitrous oxide production and emissions).

Recovered nitrogen, whether from dilute ammonium or from concentrated ammonium salts, can be used in industrial installations or as fertiliser, although large volumes make transport costly. Key nitrogen recovery technologies have been demonstrated to recover between 75 and 97 per cent of nitrogen as usable ammonia compounds, thereby reducing nitrogen and avoiding nitrous oxide production and emissions.

Nitrous oxide is produced during the biological treatment of wastewater

Switzerland provides a leading example (the only one to date, in fact) of nitrous oxide offsetting through KliK, an innovative public-private initiative that provides carbon reduction opportunities for fossil fuel importers. This includes a catalogue of carbon reduction schemes at WWTPs, including four nitrous oxide reduction options. Nine nitrous oxide schemes at WWTPs have been funded so far, most of which are still being implemented. An example is at the Altenrhein WWTP, where a scheme is enabling recovery of 75 per cent of nitrogen and reducing nitrous oxide emissions by 50-60 per cent.

OPTIMISING THE PROCESS

There are various operational strategies we can use to minimise nitrous oxide production, including balancing ammonia loads, adjusting dissolved oxygen levels and ensuring sufficient carbon where denitrification is taking place. These interventions are likely to help maintain stable conditions for biological treatment, avoiding microbial stress.

An increasing number of utilities are gaining full-scale mitigation experience and two were shared at the IWA World Water Congress in Toronto last year for the first time. Helsinki Water shared its success with increasing alkalinity and carbon dosing while the Dutch firm Royal HaskoningDHV and Dutch utility Waterschap Vallei en Veluwe have also

showed that advanced control systems can help to reduce nitrous oxide by improved control of oxygen levels in treatment zones. This prevents conditions that favour nitrous oxide production and supports its biological removal.

NITROUS OXIDE DESTRUCTION

Whilst the priority should be avoiding nitrous oxide and reducing it as much as possible, these alone are not likely to be enough. Mitigation solutions to destroy nitrous oxide are still likely to be required. Full-scale destruction of nitrous oxide from WWTPs can take place through a process called regenerative thermal oxidation (RTO). Regenerative thermal oxidisers work by heating waste gases to 800-1,000˚C; this converts the nitrous oxide to nitrogen and oxygen, as well as removing potentially harmful volatile organic compounds, carbon monoxide, ammonia and unpleasant odours – improving local air quality and community wellbeing.

Recovered nitrogen can be used in industry or as fertiliser

This ‘end-of-pipe’ solution is already being successfully used to destroy nitrous oxide in the wastewater industry, as well as in sewage sludge combustion. Notably, REAL, a system in Luzern, Switzerland, has been operating for nearly 10 years, treating off-gas from sewage sludge incineration to remove nitrous oxide. Funded by the KliK programme, the facility reduces nitrous oxide by more than 90 per cent. A second Swiss project, at the wastewater treatment facility ARA Bern, has also received funding under this programme, and will start up later in 2025.

Whilst they still do require a source of fuel, such as biogas, for operation, regenerators use energy very efficiently, with up to 97 per cent of the heat contributing directly to the process. This reduces fuel needs and cuts operating costs. Modern systems use ceramic honeycombs as heat sinks, which are resistant to chemical, thermal and mechanical influences which may otherwise reduce the efficiency of the system.

Like many other resource recovery technologies, regenerative thermal oxidisers may result in competing uses

A NITROUS OXIDE ABATEMENT HIERARCHY

for biogas at WWTPs as they do require some fuel – though they can also be heated with electrical power.

There are downsides to the RTO process: thermal destruction of nitrous oxide produces nitric oxide (NO) and nitrogen dioxide (NO₂), gases which are major contributors to air pollution. Where these exceed regulatory limits, additional steps are needed. Pilot units can be deployed for field tests at WWTPs to gather data and optimise the performance and design of the proposed RTO system.

EMERGING TECHNOLOGIES

Trials are being carried out for systems which use catalysts to enable nitrous oxide destruction to take place at lower temperatures. These are at an early stage of technological development and depend on catalyst performance and lifespan, which vary based on gas composition, moisture and operating temperature.

The priority should be avoiding nitrous oxide and reducing it as much as possible

The NACAT project in Denmark trialled lower temperature ( circa 400˚C) catalytic destruction across three full-scale WWTPs, achieving 70-80 per cent nitrous oxide removal. The project concluded that the longevity of catalysts is affected by hydrogen sulphide and methane, which could mean they have a short life and cost more to implement at some WWTPs. However, for sufficiently high-concentration nitrous oxide off-gas streams, these systems could be cost-

effective with legislation around nitrous oxide reduction proposed by the Danish government, though further work on catalyst longevity and system design is required. To date, no published data from utilities or industry demonstrates that catalytic nitrous oxide destruction at ambient temperatures is effective. More research is needed.

Biological removal of nitrous oxide from concentrated off-gas streams is another option, especially for higher strength off-gas streams. Other alternatives, such as capturing nitrous oxide-rich off-gas for combustion with fuels for heat and energy production, or using chemical sieves for recovery, also offer exciting areas for much needed research.

NITROUS OXIDE ABATEMENT TODAY

The journey to mitigate nitrous oxide emissions from wastewater treatment is complex and multifaceted. While significant strides have been made in understanding nitrous oxide emissions, the path to full-scale, sustained reduction remains challenging. Incentives, such as the Swiss KliK programme and proposed Danish regulation, are driving significant progress and showing opportunities, including for nitrous oxide removal through thermal destruction from high concentration off-gas streams.

Sharing knowledge and the ongoing lessons learned from these efforts will be invaluable in supporting global progress in water sector decarbonisation. o

Learn about CIWEM’s Wastewater and Biosolids Specialist Panel by visiting ciwem.org/communities

KAYMAC AND RIDGEWAY PROVIDE IDEAL COLLABORATION FOR SCOTTISH RIVER SCOUR WORKS

During Q2 2024, Kaymac Marine Civil Engineering Ltd and Ridgeway successfully collaborated to complete the installation of Kyowa filter unit rock bags, providing scour protection to critical infrastructure. Working closely with Kaymac’s engineering design and procurement team, Ridgeway sourced the approved stone material, prefilled the rock bags and delivered them to the site location in Grangemouth, Scotland. Made of 100 per cent recycled polyester (rPET) and constructed using a unique form of knitting known as Raschel, the Kyowa filter unit is a rock-filled bag containing aggregate, making it a highly flexible solution for marine construction work. This approach was selected for its effectiveness in safeguarding riverbanks and structures from erosion while minimising environmental impact. Kaymac was responsible for developing the method for installing a haul road along the riverbank, as well as placing Kyowa rock bags to prevent further scour. The project posed several challenges, including working in a tidal river environment, navigating highvoltage cables and contending with

harsh weather conditions.

A methodology was devised by the Kaymac engineering team and approved by the Marine licensing body, enabling operatives to effectively install the scour protection while addressing site constraints.

To ensure safety while protecting the riverbank, the rock bags were placed at a calculated distance from the haul road to prevent undue stress on the scoured bank. The bags were transported from the compound along the haul road to the affected area and then carefully placed using a long-reach excavator. Given the site and licensing constraints, major excavations were not feasible, so only minor reshaping was undertaken before placement. Through meticulous planning and coordination, the team overcame these challenges, completing the project on time and to the client’s satisfaction.

The rock bags provided a sustainable solution by stabilising the riverbank while supporting vegetation growth and offering a substrate for aquatic life. Additionally, Ridgeway ensured that the stone used inside the bags was locally sourced, utilising local labour to reduce carbon emissions.

This project exemplifies Kaymac and Ridgeway’s shared commitment to delivering innovative, sustainable solutions that protect both critical infrastructure and the natural environment. o

T: 01792 301 818

E: Enquiries@kaymacltd.co.uk

Ridgeway Rockbags www.rockbags.com

T: 028 9045 4599

E: info@rockbags.com

TO HAVE AND TO HOLD

Retrofitting SuDS at scale has huge potential for reducing runoff to sewers, but this technology only works if it’s properly maintained, writes Kevin Barton, landscape architect and managing director at Robert Bray Associates

Sustainable drainage systems (SuDS) are a disruptive technology. SuDS are modifications to a development or existing urban landscape that allow it to manage rainfall in ways that offer multiple benefits. They’re a means of treating urban pollution, creating better places for people and wildlife, reducing overflows from combined sewers, and improving climate resilience – including helping to reduce flooding. Disruptive technologies are powerful forces for change but they bring with them challenges that can serve to inhibit progress. One of those challenges is

maintenance. This is particularly relevant in relation to retrofit SuDS, but also to new development. Delivering and maintaining amenity value – general benefits to users of the area such as health and wellbeing, play, visual amenity, urban cooling and nature contact – should be top of our agenda when installing SuDS – no matter your delivery priorities.

The fact that we don’t have the skills and money to maintain nature-based SuDS is only relatively recently being recognised as a significant barrier to the kind of SuDS rollout that we all want to see in the UK. Ask any landscape architect and they will tell you two

things: firstly, that this problem is not unique to SuDS – it’s a general and deeply frustrating problem afflicting most public green infrastructure initiatives. Secondly, it’s an issue that has been growing for decades and is still getting worse – council budgets are not going up and maintenance skill levels appear to be continuing to decline. Throw in the ambitious scale of additional SuDS landscapes in planning for the public realm in the coming decade, on top of the existing maintenance issues, and we have a big problem we need to solve. We can’t hide behind a mythical notion of near-to-zero maintenance raingardens.

KEVIN BARTON

Community-focused SuDS at Bridget Joyce Square, White City, London

UNREALISTIC EXPECTATIONS

Here at Robert Bray Associates, we recently had a tender invitation that included an ambition for the raingarden design to be ‘self-maintaining’. Here we see an unwitting illustration of the pitfalls of applying conventional drainage thinking to blue-green infrastructure: the ‘self-cleansing velocity’ of pipe design meets landscape maintenance. The client presumably knew that ‘zero maintenance’ wouldn’t fly, and opted instead for the more palatable ‘self-maintaining’.

Maintenance of SuDS landscapes is not just about delivery of aesthetics and the soft benefits of SuDS – as the amenity and biodiversity benefits of SuDS are too commonly regarded. It is a critical part of ensuring continued hydraulic functionality. One of the characteristics that makes SuDS a disruptive technology, contrasting with much conventional drainage maintenance, is that ongoing, proactive, scheduled maintenance is required to maintain any or all of the ‘four pillars of SuDS’ functionality (amenity, biodiversity, water quality and water quantity, according to CIRIA).

Added to that, the manner, equipment and skills of maintenance are radically different from those required for conventional drainage. Maintenance of vegetation in urban landscapes normally sits within the remits of parks, greenspace and public realm departments rather than with highways and drainage, or with water companies who may now feel that SuDS installations are their responsibility. This ambiguity only amplifies the disruptive impact of SuDS on the industry. Whose runoff and silt is it? Who pays whom to carry out maintenance? And do different council departments pay for and carry out different aspects of maintenance?

Nature-based SuDS cannot be fit-and-forget, zero maintenance. We should also be wary of aiming for as close to zero as we can get. Again, most landscape architects will accept that, on the whole, the potential community and wildlife benefits of a landscape reduce as we design for decreased maintenance budget. Whilst the industry is exploring new approaches to plant species, substrates and mulches to deliver more with less, there’s only so low a bar can go when we’re talking about living

organisms, before what we’re delivering becomes devalued to breaking point or risks losing its community and wildlife value soon after completion.

It would be better to deliver fewer SuDS and retain – and ring-fence – the budgets to maintain them properly – even if this means challenging and re-writing the ‘rules’ around capital investment and maintenance funds. Disruptive technologies call for new rules. If the infrastructure we install is kept functional and multi-beneficial, this could result in better overall performance outcomes on multiple fronts in the longterm. Better that than building more SuDS and them failing due to neglect.

CAN COMMUNITY MAINTENANCE SAVE THE DAY?

No (and yes). I’m not an advocate for free community maintenance. It’s wonderful to have locals wanting to maintain SuDS for free – and we have schemes in Wood Green, North London, where this is the case – but we have to be very careful when adopting this as a strategy.

Some questions to consider: does the community have the necessary skills and equipment to maintain the SuDS, including the more technical bits like checking inlets, outlets and flow controls? Do they have the training, competence and equipment to safely maintain green infrastructure adjacent to highways? How will it be guaranteed or contracted that they will maintain the SuDS to an acceptable standard, and how will this be supervised? What happens if the community impetus fizzles out and they stop maintaining the SuDS? Will this be identified before weed infestation? In case of performance failure, how will the maintenance be taken back into council (or another body’s) control?

We can’t hide behind a mythical notion of near-to-zero maintenance raingardens

But perhaps the biggest issue with free community maintenance is that it relies on good will, which is typically a finite resource. Fine for the odd pilot, but we should be well beyond pilots by now and we urgently need to be thinking about rolling out this infrastructure on community, town and city-scale. As we

scale up SuDS retrofitting, that holy grail of free community maintenance will feel like a distant dream.

The other issue of relying on community maintenance is that we risk concentrating SuDS and the benefits they bring – to health, wellbeing, quality of life, climate resilience, property values and more – in the typically more affluent communities and demographics with the capacity to maintain them for free. This could mean that more vulnerable communities miss out on the muchneeded co-benefits of SuDS.

It’s just not a viable solution at scale – and nor should it be. People don’t maintain gullies and pipe networks, have to cart all their refuse to recycling centres themselves, or maintain the roads outside their houses. Why should we expect them to maintain this new, better form of drainage infrastructure, just because it brings them co-benefits?

CONTRACTED COMMUNITY MAINTENANCE

I advocate community maintenance of SuDS being valued as an essential service and therefore rewarded, specified, contracted and performancemonitored appropriately.

At Bridget Joyce Square, our awardwinning, community-focused SuDS project in White City, London, the highlyvalued urban park is maintained by a local community charity, Hammersmith Community Gardens Association (HCGA). They are under contract to the London Borough of Hammersmith and Fulham and are paid for their service. They run a smallholding locally and so the staff know how to maintain landscapes, and they are an active part of the community, dedicated to maintaining the community value that the park delivers. They use local volunteers as well as corporate volunteers to carry out the maintenance, under skilled supervision, and because they walk through it on the way to work, they are proactive in their maintenance programming.

The charity wins because it brings in much-needed revenue, which supports their amazing work with the local community. The community wins because they have a valuable landscape that is properly maintained by members of their own. The council wins because they get reliable, effective and cost-

effective maintenance and a landscape investment that is valued and protected by the local community. In fact the model has been so successful that the council has contracted them to plant and maintain a tranche of new raingardens we designed for the estate, as well as a few other landscape projects in the area.

A bit of digging around will identify similar horticulture-based grassroots organisations and charities that could be approached to deliver similar services, bringing them revenue and public profile benefits. Where these groups don’t exist, we need to accept that we must invest as much in nurturing the long-term success of SuDS installations as we do in their initial construction.

THE MOST IMPORTANT ‘PILLAR’ OF SUDS?

Whilst I strongly advocate for delivering the appropriate balance of the four pillars of SuDS, there is one pillar that outstrips the others in importance. Designing for amenity value – and paying to maintain that value – should be the paramount focus of any SuDS project in the public realm, no matter your primary objectives. This is because it’s the aspect of SuDS that can either unlock or inhibit successful delivery and maintenance depending on how it is approached.

It would be better to deliver fewer SuDS and retain the budgets to maintain them properly

Even if we were only targeting hydraulic performance – reducing the rate and volume of flows discharging from the system – if the SuDS do not deliver meaningful benefits to the host community, then issues can arise that jeopardise our wider hydraulic objectives such as flooding. The first is public rejection of or indifference to SuDS installations, resulting in a lack of care, vandalism, damage, lack of reporting of maintenance issues and lack of community pressure on councils to look after them properly. All this is important because it can potentially result in performance loss or failure. If an unappealing SuDS installation is a blot on the landscape from the start and is essentially useless to the local community, are people going to

care or even notice when it’s silting up, damaged, failing or receiving foul sewage from misconnections? Are they going to park on highway raingardens because they didn’t deliver perceivable public value and didn’t properly consider public needs and behaviour?

SuDS installations with low public value that result in negative public perception make it difficult to engage local communities and get their approval for more SuDS. This risks impacting the rate or ultimate scale of rollout. I’ve experienced this negative public feeling directly, and believe we may already be in the early stages of a vicious cycle of descending public perception in the UK.

If the communities we are engaging with have only experienced SuDS with low amenity value, or poorly maintained SuDS, or have only heard of them through negative press coverage, then convincing them of the potential of putting SuDS in their community gets much harder. If we struggle to convince the broader public beyond a few pilot projects, then we may struggle to achieve the scale of retrofit SuDS that we need.

For community maintenance structures to be viable, SuDS need to bring real, meaningful value to those communities. Charities and community groups are far more likely to be willing to maintain projects that have a genuine design emphasis on meeting community needs. Such projects can generate a virtuous cycle of positive public perception of SuDS, leading to public buy-in and a smoother roll out of subsequent projects. Hydraulic functionality should be a given, not a driver of design. Instead of being seen as a soft benefit or a nice to have, the broad range of human benefits that are so inadequately summarised as ‘amenity’ in the SuDS world should be at the forefront of SuDS design. Such an approach should enable us to implement projects that communities actually value. Only by doing so will we achieve the rollout of SuDS at the pace and scale we urgently need, and secure their continued functionality into the future. o

To connect with other members working with SuDS, join CIWEM’s Urban Drainage Group. Learn more at ciwem.org/communities

Poorly maintained sustainable drainage schemes (SuDS) create negative public perception that will hinder a wide-scale rollout of this technology

KEVIN BARTON

Robust survey data to meet your project needs

Support your projects with environmental survey data tailored to your requirements

As part of our integrated marine consultancy and survey offer, ABPmer’s specialists collect, process and interpret all types of survey data

Marine and coastal ecology

Marine mammals and ornithology

Habitat sampling and mapping

Topography, bathymetry and geophysical

Waves, hydrodynamics and water quality

Vessel traffic monitoring (ships / boats)

Marsh Nutra-Lite SBR

sewage treatment plant

Marsh Phos-Lite Phosphate reduction unit

READY OR NOT

Charlotte Jones of National Flood Forum and flood risk consultant

Paul Cobbing on Resilient Roch, a project identifying and addressing the barriers to flood and climate resilience in vulnerable communities

People might know they are at flood risk – but if they’re struggling to pay the bills, pay the rent and keep food on the table then they won’t be thinking about the potential of flooding, no matter how much upset that will cause to their lives.”

These are the words of a local government officer in the North West, quoted anonymously in the Rochdale Flood Poverty Report, who admitted that policy makers were “not in touch” with the extent of the challenges that people at socio-economic disadvantage faced. Produced by Rochdale Borough Council in 2024 and supported by National Flood Forum, the report set out to explore these challenges. The Resilient Roch project is part of our response.

Resilient Roch is part of the government’s Flood and Coastal Resilience Innovation Programme (FCRIP), which sees 25 projects testing and developing innovative new approaches that will reduce risk and increase flood resilience. The aim is to encourage behavioural change and new ways of working with and within floodaffected communities.

Working in two communities in Rochdale, Greater Manchester, we’ve taken a more holistic climate-resilience approach to property resilience, seeking to deliver more flood-resilient and warmer, more energy-efficient homes for the future. We are supporting residents, schools and businesses to be more aware of their flood risk, confident about taking ownership of

it and helping to manage it more effectively as individuals and neighbourhoods.

VULNERABLE COMMUNITIES

It will not be a surprise that in Rochdale, as indeed in many older urban settlements, we found a correlation between flood vulnerability and social vulnerability. Communities may be transient. Landlords may be absent and unwilling or unable to maintain their properties. People who are vulnerable are likely to have more immediate priorities than flooding, except when the floods arrive. These factors, among many others, heavily impact the community’s capacity to employ the self-led flood resilience techniques and processes that we encourage as a society and as a

The River Roch gives Rochdale its name

sector. And even when these traditional approaches are adopted, they reduce risk but do not eliminate it. People are still at risk and need both the vigilance and capability to be able to respond individually and as a community.

Community preparedness requires support and investment

In low-income areas the impact of flooding on people can be greater because they may be more vulnerable and do not have the resources to cope, especially if they lack residential property insurance. With the average insurance claim for buildings residential insurance topping £30,000, this is well beyond the ability of most people in our target areas.

The Rochdale Flood Poverty Report recommended that in addition to traditional flood risk management methods (such as structural defences like walls and engagement methods like flood warden systems), a more cross-sectoral and integrated approach should be taken to developing and maintaining a broad definition of resilience that includes community, financial and physical aspects.

BEYOND RISK MANAGEMENT AUTHORITIES

The first focus of Resilient Roch is to ensure that any resilience measures are installed and subsequently maintained correctly, and with support and guidance provided by the local authority. There is an emphasis on ensuring residents have both the measures and the knowledge needed for them to be effective.

The second focus is on resilient behaviour, which involves building community capacity for collective preparedness on top of traditional understandings of personal resilience (knowing your flood risk and being prepared). For example, we will be working with property flood resilience (PFR) companies to develop training for local tradespeople in maintaining PFR correctly and ensuring that non-flood related work they carry out helps and doesn’t hinder flood resilience.

This moves beyond the premise that increasing flood resilience is only delivered through the recognised risk management authorities such as the Environment Agency, lead local flood

authorities and utility companies. Our project aims to embed delivering better flood resilience into the remit of a much broader suite of organisations working in these communities. Organisations such as Rochdale Boroughwide Housing, Groundwork (who support communities through schemes that provide social benefits), Citizens Advice, and very local community and faith-based projects and organisations are all playing a role in supporting day-to-day flood resilient behaviour and practice.

PROPERTY FLOOD RESILIENCE

Resilient Roch is combining flood resilience with energy efficiency measures, like insulation, whenever possible on individual properties in our two target areas of Wardleworth and Littleborough, creating more sustainable and climate-resilient homes. We’ve surveyed over 200 properties for flood resilience measures to date, and the installation process is currently underway. Where eligible we’ve carried out energy efficiency surveys to identify measures to make homes warmer.

Littleborough and Wardleworth are two of Rochdale’s highest flood risk areas. Despite being geographically close, the areas are demographically quite distinct. Whilst Wardleworth experiences high levels of multiple deprivation, more subtle forms of deprivation can be found in parts of Littleborough, where some households are ‘property rich and cash poor’ as many of the residents have very little disposable income even if they do own a home. This leaves them with little money for retrofitting for flood resilience. These contextual issues need careful

THE FLOODING AND DEPRIVATION LINK

PEOPLE WITH FEWER resources move to areas with cheaper housing – either renting or owning. Cheap housing may be cheaper because it is in poor condition and/ or it is at risk of flooding and is therefore attractive as ‘buy-to-let’ investments.

Many landlords and homeowners do not or cannot afford to invest in their properties to make them or keep them habitable.

When flooding occurs many houses are vulnerable due to poor build and maintenance.

After flooding, homes may not be dried out and/or reinstated, leading to damp-related health issues and increased heating costs.

People without residential property insurance are particularly vulnerable – they bear the costs or live in damp and mouldy homes – both are drivers for deprivation and poverty.

consideration when working in and with these communities.

We are engaging the local community through multiple channels and introducing property-level solutions that will have long-term benefits for residents’ wellbeing and the environment. For example, warmer, flood-resilient and airtight homes will be less damp, less likely to flood and will require less energy to keep warm, saving residents money.

Working with Rochdale’s housing team and the lead local flood authority on property climate resilience maximises the added values from the project. By aligning investment better, we have unlocked economic benefits for the borough.

A Rochdale property in need of attention

The approach means we can signpost any issues to other council services, for example around wider property condition or health and wellbeing issues.

COMMUNITY ENGAGEMENT

We’re building upon longstanding engagement work in our community with the National Flood Forum. Partnered with the council since 2013, the charity has developed in-depth knowledge and strong relationships with the community, helping to increase awareness of flooding and develop the confidence to adopt more resilient behaviours.

Affordability is still a barrier to insurance despite Flood Re

Having a third party – an honest broker that can work in and with communities – to build trust is key to the project’s success. This is especially the case where people feel disenfranchised from years of consultation and ambivalent about any form of engagement with authority. This work takes place on many fronts, collaborating with the many organisations that are active in communities, working in schools, with flood action groups, street champions and more. Climate change hubs are being developed as a place for knowledge sharing, meetings, exhibitions and workshops. Where language proves a barrier to engagement, community groups such as the Rochdale Women’s Welfare Association have helped with translation, providing an essential bridge to ensure that our messages reach those who might face cultural barriers.

Another notable example of collaboration with existing organisations is the work with the Rochdale Citizens Advice Bureau (CAB) on flood insurance and signposting people to accessible, affordable and appropriate insurance. On most weekdays CAB employees sit at the front of Rochdale central library supporting residents with dozens of queries a day. They are a present and trusted source of information.

THE INSURANCE CHALLENGE

Residential property insurance is probably the single most important thing that people can do to protect their

financial resilience in flood risk areas. Having surveyed residents on property flood resilience and energy efficiency retrofit measures, we found that roughly one third of people had residential property insurance, one third did not and a third did not know. Promoting insurance uptake as part of the overall approach in the target areas is an integral part of our approach, working with the insurance industry and organisations engaged with the communities.

In many low-income households, affordability is still a barrier to insurance despite eligibility for the governmentbacked Flood Re scheme. We have begun to investigate the possibilities for insuring these households, exploring how social housing providers can provide access to affordable insurance.

LOOKING FORWARDS

Community preparedness requires support and investment. Particularly in vulnerable areas, the capacity for preparedness and resilience needs to be built in by addressing the multitude of factors that make people vulnerable. Preparedness can only be achieved when community capacity is built up through whole society and climate resiliencebased approaches.

The project begins to explore concepts of what resilience and social justice really mean and how flood risk management can address these issues in different types of communities. We are halfway

CIWEM’S PROPERTY FLOOD RESILIENCE INITIATIVES

PFR IS CRITICAL to protecting homes and businesses, but a lack of confidence and consistency in its delivery has led to low levels of uptake and quality. So in spring 2025, CIWEM launched a specialist professional register of PFR professionals. It provides an independent, recognised benchmark of competency for those delivering PFR measures, building on our BeFloodReady Community of Practice and comprehensive training programme. For more infomation, visit befloodready.ciwem.org

through the programme now and have until 2027 to fully develop the impact of our practices. We will continue to bring the community alongside us as we deliver more PFR installations, community level SuDS (see ‘To have and to hold, pp. 24-26), further insurance training for existing community support groups, and develop community hubs that will ensure the aims of the project have a lasting legacy. Along the way, we are looking for any opportunities that arise to develop or mainstream some of our key practices. For example, how we engage on flood resilience and how properties in the social housing sector are maintained. While we are already involved in disseminating some of our learning, we are always looking for further opportunities to do so.

We hope to create warmer, drier homes where people have greater confidence in their ability to be climate resilient. We also want to support residents in building positive relationships with flood risk management agencies and have the confidence to collaborate with them to manage flood risk in their communities. Where communities are effectively engaged, better environments are made for managing flood risk. This looks like communities where residents understand how to be physically, socially and financially resilient, and if they are not (because not everyone will be), there are always organisations present that have the right knowledge to support them.

At the end of the project, we also hope that we can prove the economic and social benefits of combining energy efficiency and PFR measures. We know it is possible and replicable, and soon we hope to share more of our successes.

After the project ends, its legacy will continue: community hubs, better informed residents, more climateresilient homes, more nature-based solutions providing multiple benefits, and continued multi-agency working. We hope that our innovations will be further developed elsewhere. o

Fran Comyn of Rochdale Borough Council and Resilient Roch will be taking part in a session on ‘Building climate resilient communities’ at Flood & Coast 2025. Book your ticket at floodandcoast.com

GREY ENABLING GREEN: BUILDING CLIMATE-RESILIENT CITIES THROUGH HYBRID INFRASTRUCTURE

By Martin Lambley, Senior Global Product Manager –Urban Climate Resilience, Wavin

As climate change accelerates and urbanisation continues, cities across the UK are under unprecedented pressure to manage surface water more effectively. Flood events are increasing in both frequency and intensity, ageing infrastructure is struggling to cope, and the need to deliver sustainable, resilient solutions has never been more urgent.

At Wavin, we believe that the key to long-term water resilience lies in the intelligent integration of grey and green infrastructure – a concept we call Grey Enabling Green. Through a combination of engineered reliability and natural, sustainable processes, we can transform our urban environments into smart, adaptive systems that are fit for the future.

A NEW REALITY FOR URBAN WATER MANAGEMENT

The challenges we face are not abstract. They are already here. Surface water

flooding is now the most common form of flooding in the UK. Increased impermeable surfaces from urban expansion mean more runoff, while extreme weather – exacerbated by climate change – pushes our drainage systems beyond their limits.

Historically, the response has been to invest in large-scale “grey” infrastructure – engineered systems such as sewers, culverts and concrete channels. These are robust and effective at transporting water, but they come at a cost: high capital investment, inflexible design and disruption to ecosystems. Moreover, grey systems alone often cannot adapt to changing conditions or support broader environmental goals.

Conversely, ‘green’ infrastructure – rain gardens, swales, green roofs and wetlands – offers sustainability, biodiversity and beauty. These nature-based solutions help infiltrate, filter and evaporate stormwater, while improving air quality and urban

cooling. However, they can be limited by space constraints, establishment times and unpredictable performance under extreme weather conditions.

Rather than choosing between the two, Wavin’s approach is to integrate both – using engineered systems to enable, support and optimise nature-based drainage. This hybrid thinking is essential if we are to build cities that are not only flood-resilient but also environmentally and socially vibrant. Why grey and green need to work together:

● Increased rainfall intensity due to climate change

● Rising impermeable surfaces from urbanisation

● Ageing infrastructure under strain

“Surface water flooding is now the most common form of flooding in the UK.”

WHAT GREY INFRASTRUCTURE OFFERS

Engineering certainty in a changing world. Grey infrastructure such as pipes, tanks, and attenuation crates offers reliability

Integrated grey and green infrastructure is key to liveable, climate-resilient cities

and high performance under extreme conditions. Wavin’s AquaCell NG system exemplifies our commitment to engineered excellence in stormwater management.

“Grey systems are not the enemy of sustainability – they’re its backbone.”

THE POWER OF GREEN INFRASTRUCTURE

Nature-based systems like swales, green roofs and rain gardens add ecological and social value. Though they require space and time to establish, they enhance urban biodiversity, cooling and water quality.

HYBRID SUDS IN ACTION

Across Europe and the UK, Wavin has implemented hybrid drainage systems that demonstrate how grey and green can work hand-in-hand to deliver resilience at scale.

COPENHAGEN CLOUDBURST PLAN

Copenhagen has become a global model for climate-adaptive infrastructure. Following a catastrophic flood in 2011, the city launched its Cloudburst Management Plan, combining both traditional grey systems and naturebased solutions. Wavin contributed to projects where sewer networks were expanded, roads re-engineered to store water temporarily, and green surfaces –including parks and permeable pavements – were deployed across the city.

AMSTERDAM ROOFTOP PLATFORM

In Amsterdam, Wavin supported a smart, multi-site roof attenuation system covering 21 rooftops, with capacity for future expansion. The solution integrates live monitoring and adaptive control, ensuring rainwater is temporarily stored and released without overloading the sewers. This type of decentralised, networked infrastructure reduces downstream pressure and adds green value to dense urban areas.

LONDON SMART RAIN GARDEN

In London, we helped implement a smart rain garden as part of a wider SuDS scheme. The system enhances traditional attenuation performance while introducing planting, filtration and biodiversity gains to the streetscape. By combining shallow subsurface tanks with sensor-controlled overflows, the garden delivers both hydraulic protection and environmental improvement.

SMART DRAINAGE: THE DIGITAL LAYER

A key enabler of hybrid infrastructure is digital technology. Wavin’s smart drainage systems incorporate sensors, telemetry and remote flow control to create responsive, data-driven drainage networks. These systems adjust dynamically to weather conditions, optimise discharge rates and notify operators when thresholds are exceeded. This “Smart SuDS” approach aligns with emerging industry best practice and upcoming regulatory expectations around performance monitoring and maintenance planning. It also ensures infrastructure remains efficient and cost-effective over its lifecycle.

COLLABORATION AND POLICY: MAKING IT HAPPEN

While the technology exists, sustainable water resilience cannot happen in isolation. Integrated, hybrid infrastructure requires collaboration across the supply chain – from engineers and developers to local authorities and regulators. It also demands enabling policy. Planning guidance must go beyond box-ticking and incentivise genuine multifunctional design. Funding should support innovation, especially where long-term operational savings outweigh upfront costs. Community engagement and education are essential to ensure SuDS are valued and maintained over time.

ABOUT WAVIN

WAVIN IS A leading provider of sustainable water and drainage solutions with over 60 years of expertise. A pioneer in SuDS and surface water management, Wavin continues to innovate in climate resilience, working with partners across the built environment to create cities that are smarter, greener and better prepared for the future.

At Wavin, we actively engage with stakeholders across the SuDS community, contributing to national working groups, sharing best practice and advocating for evidence-based, integrated planning.

“It won’t happen in isolation. We need policy, funding and community engagement.”

SMARTER, GREENER, COOLER

CITIES

Grey enables green. Engineering provides the foundation, nature provides the resilience. Together, they create cities that can not only survive extreme weather – but thrive in the face of it.

As we look ahead to a climate-uncertain future, the way we design and manage our drainage infrastructure will define the resilience of our towns and cities. Grey and green must not be seen as competing ideas, but as mutually reinforcing tools in a holistic, adaptive approach.

Engineered systems bring precision and confidence. Green infrastructure brings flexibility and environmental value. Together, supported by digital innovation and collaborative policy, they offer a blueprint for sustainable urban living.

Wavin’s Grey Enabling Green vision is not just a theory – it’s a reality already being delivered on the ground. Through innovation, partnership, and commitment, we’re helping to shape cities that are not only protected from floods but enriched by nature. o

For more information, visit: https://solutions.wavin.com/en-gb/ urban-climate-resilience @WavinUK

Community planting on a raingarden project

– Tom Boichot, Head of Wastewater Enhancement

SUPPLY AND DEMAND

Simon Harrow, interim director of water resources at Ofwat, reflects on water company plans to ensure water security in England and Wales

Projections in the latest water resources management plans indicate that without action, England and Wales could face a shortfall of around five billion litres of water per day by 2050. This is equivalent to a quarter of the water currently put into supply – and the figure could increase as estimates are updated.

The shortfall is primarily due to a combination of climate change, population growth and environmental requirements to reduce abstraction from natural sources such as streams and aquifers. This supply gap is intended to be addressed through tackling leakage, increasing water efficiency and the delivery of new infrastructure for water supply. But complexity continues to grow.

Firstly, demand from businesses and agriculture is placing increasing strain on water demand. This type of use, which is not necessarily reliant on water company supplies themselves, but which impacts water availability overall, adds to the intricacy of the water resource challenge.

Secondly, we have seen mixed success by water companies delivering their water resources management plans (WRMPs). As part of the WRMP process, water companies produce an annual review of their plans, which sets out how they are delivering the commitments set out in their WRMPs. Ofwat and other regulators review these submissions, and where regulators have deemed companies to be off track in delivering their WRMPs, companies receive joint

letters citing our concerns. These letters are an escalation measure, signalling the need for immediate improvement. Ten letters were sent to companies in relation to 2023-24 performance. Companies are also required to develop action plans and be subject to six-monthly progress updates. Under delivery by some companies has a knock-on impact on addressing our water needs for years to come.

Thirdly, it is no secret that public confidence in the water sector is currently low, driving concerns over the sector’s ability to deliver on the ambitious £104 billion package set out at PR24, the price review for water companies in England and Wales. With the increased funding in Asset Management Period 8 (the five-year regulatory period that runs from April 2025 to 2030, known as AMP8) comes a considerable shift in our expectations of water company delivery – and we acknowledge that the sector needs a step change to meet those expectations.

Furthermore, the urgency of delivery on environmental requirements, as well as the government’s emphasis on the growth agenda, means there will be additional pressure to accelerate the delivery of new water infrastructure.

PLANNING FOR FUTURE WATER SUPPLIES

Water resources management plans are produced by water companies to provide an overview of their supply resilience and the investment they need to make improvements. The plans set out how a company intends to develop its water resources to provide customers with a secure supply of water over at least 25 years. They are prepared every five years and reviewed annually. WRMPs focus on an extreme scenario: times of drought, when available water is at its lowest, but demand at its highest.

We have seen mixed success by water companies delivering on their water resources management plans

Where a company identifies that it would not meet demand during a forecast drought within the next 25 years, they will need to develop new supply-side solutions or reduce the amount of water needed. The companies then identify and evaluate feasible supply and demand options before confirming their preferred programme, showing how this would deliver the resilient water supply required. Companies that do not forecast a deficit should still consider options for improvement – for example, addressing leakage or enabling water trading between regions (transferring water from a place with a surplus to one experiencing a deficit). The most recent round of WRMP planning was the first time there was full coverage of planning groups for England, with five regional groups covering the entire country and ensuring consistency of interactions between regions. This has supported improved WRMP outcomes, such as more transfers and better crosssector working, although it has also added an additional layer of complexity.

INCENTIVES AND PERFORMANCE

As part of the sector’s need to address our water security at pace, Ofwat is driving and incentivising improvement in performance.

2025-30 RAPID WATER SUPPLY PROJECTS

Leakage performance is variable between companies, but the trend across the sector has been broadly positive.

We introduced a 15 per cent leakage reduction challenge in our 2019 price review in an attempt to address a longrunning trend of stagnating performance. This was followed by Water UK’s industry commitment to reduce leakage by 50 per cent by 2050 from a 2017-18 starting point. Recent reductions from 2017-18 to 2023-24 (a period of seven years) shows a reduction in the volume of leakage of over 10 per cent. This compares to an approximate four per cent reduction over the preceding 17 years from 2000-01.

We are now backing continued leakage improvement, with 2024 Price

Review (PR24) targets that would result in an additional 17 per cent reduction over 2025-30. Our PR24 decisions support companies to invest £720 million of enhancement funding to achieve this, using better data, including from expanded metering coverage (see ‘Work smarter, not harder’, in the Spring 2025 issue of The Environment).

In addition to addressing leakage, we must reduce overall water demand. Water companies are aiming to reduce per capita consumption from an average of around 136 litres per person per day to 110 litres by 2050.

Rolling out smart metering is central to both identifying leakage and increasing water efficiency. Companies have been

funded to deliver 10.4m smart meters at properties over 2025-30, at a cost of £1.7 billion. This is a significant increase –with around 50 per cent of households and businesses expected to have a smart meter installed by 2030, up from 13 per cent of households currently.

Reducing demand for water is usually more environmentally friendly and can be cheaper than new supply schemes. We are challenging the sector to save eight litres of water per person per day over the 2025-30 period, alongside new targets for reducing business use.

NEW WATER SUPPLY INFRASTRUCTURE

Reducing leakage and demand alone cannot fully meet the water resource challenge we face in the coming decades.

That’s why RAPID – the Regulators’ Alliance for Progressing Infrastructure Development, a joint programme between the Environment Agency, Drinking Water Inspectorate and Ofwat that was launched in 2019 – is overseeing the biggest package of large water supply projects since the privatisation of the sector (see map).

This includes development of nine new reservoirs, plus converting an existing

WATER EFFICIENCY FUND AND SMART WATER METER DELIVERY GROUP

OFWAT IS LEADING a new Smart Water Metering Delivery Group with government and regulators to improve the efficiency and effectiveness of the industry smart meter roll out. We are also setting up a £100 million water efficiency fund. This will support collaborative and innovative work needed to deliver a transformative, sustained and measurable reduction in demand. There are two workstreams with the fund:

The Water Efficiency Campaign will promote behaviour change that encourages people and businesses to use less water.

The Water Efficiency Lab will fund the development of new technologies and processes for water efficiency. It will be open for applications later in 2025.

quarry to a reservoir. Once completed after 2030 these reservoirs alone have the potential to produce 670m litres of extra water per day.

We are also supporting plans for nine new large-scale water transfer projects to transport water across company regions. Most use new pipelines, with the Grand Union Canal scheme combining a new pipeline with existing canal infrastructure In addition, PR24 allows £2bn to build over 300km of interconnectors, joining up supply systems to improve resilience and help keep water available during drought.

As well as addressing leakage, we must reduce overall water demand

Also included in PR24 is funding of the early development of 12 water recycling plants which accelerate the natural water cycle by reusing treated wastewater and two desalination sites.

In total, our decisions have allowed funding of £5bn to expand supply. This includes 424m extra litres per day –currently over three million people’s usage – to be delivered by 2030 through new and upgraded groundwater sources, expanded water treatment works and relocating abstractions.

This diverse range of options should enable us to reduce abstraction from sensitive sources such as our unique chalk streams.

STEP CHANGE

Five years ago, I wrote an article for this magazine arguing for smarter regulation to promote smarter water resources. The leakage challenge and subsequent leakage targets, the development funding for large supply infrastructure, and the launch of RAPID are improving the picture, but there’s still a way to go. What’s needed now is enhancing the co-ordination of delivery, robust tracking of company delivery, identifying opportunities and synergies (such as between water and energy sectors), and advocating a stronger national view on planning.

We also need to bring the public on this journey with us – raising awareness of the water security challenges we face in England and Wales and ensuring there is understanding and support for the actions we all need to take. That’s why Ofwat is investing in a major public education campaign on water efficiency to be delivered in the coming years, as well as co-ordinating the smart meter rollout.

It is important that we take a collaborative approach to ensuring our water resilience. That includes supporting a common understanding and public action on reducing personal consumption, promoting innovative approaches to efficiency, and facilitating cross-regional and cross-sector partnerships to deliver new supply infrastructure at pace. We must continue to face this challenge together. o

Water companies have committed to delivering a 50 per cent reduction in leakage from 2017-18 levels by 2050

FLOOD

£33,366

£42,512

£52,290-

£30,195

POLICY TEAM WELCOMES NEW MEMBER OF STAFF

THE POLICY TEAM is delighted to welcome Isabel Thompson. Isabel joined CIWEM as a policy officer in March, following marine policy internships at the Marine Biological Association and the Marine Stewardship Council. She also worked for the charity Seas Your Future as a science educator aboard the Tall Ship Pelican. Here she tells us about herself...

WHAT DID YOU STUDY AT UNIVERSITY AND WHY?

I studied marine biology and oceanography (MSci) at the University of Southampton. I have a deep love for nature and the ocean, and have always wanted to explore the natural world whilst learning skills that mean I can make a positive contribution.

WHAT IS YOUR FAVOURITE SPOT TO ESCAPE TO IN NATURE?

My favourite regular escape spot is the south coast. I enjoy road trips with friends to surf, scuba dive or just swim in the sea, no matter how cold the water!

WHAT ATTRACTED YOU TO THE ROLE OF POLICY OFFICER?

It’s an excellent opportunity to expand my knowledge beyond the marine environment and learn more about the freshwater realm. I know that through discussions with my colleagues and with the wonderful community of experts I will learn an incredible amount and be able to make a positive contribution to the natural world that I love so much.

WHAT DO YOU HOPE TO ACHIEVE IN THE ROLE?

The overarching hope is to contribute towards positive policy change. On a smaller scale it’s to be able to contribute towards important documents, facilitate conversations that help change people’s minds about green solutions and empower people to use their positions for good.

JFRM BEST PAPER AWARD 2024

OZIUS DEWA, DONALD Makoka, and Olalekan A Ayo-Yusuf have been selected as the winners of the Journal of Flood Risk Management Best Paper Award 2024 for their paper, “Measuring community flood resilience and associated factors in rural Malawi”. There were also four highly commended articles for this year’s award:

1. “Assessing Greek small and mediumsized enterprises’ flood resilience capacity: Index development and application” by Antonis Skouloudis,

Walter Leal Filho, Panagiotis Vouros, Konstantinos Evangelinos, Ioannis Nikolaou, Georgios Deligiannakis and Thomas Tsalis

2. “Evaluation of an early flood warning system in Bamako (Mali): Lessons learned from the flood of May 2019” by Nanée Chahinian, Matias Alcoba, Ndji dit Jacques Dembélé, Fréderic Cazenave and Christophe Bouvier

3. “Toward an adequate level of detail in flood risk assessments” by Tobias Sieg, Sarah Kienzler, Viktor Rözer,

NEW EDITORS-INCHIEF AT JFRM

THE JOURNAL OF Flood Risk Management, sister title to The Environment, in January welcomed Professor David Proverbs and Professor Nigel Wright as co-editors in chief. They took over from Dr Paul Samuels, who led the journal for 11 years.

David is associate pro vicechancellor for enterprise and business innovation at De Montfort University and an independent member of the Environment Agency’s Regional Flood and Coastal Committee. He is a visiting professor at universities in the UK, China and Brazil. Nigel is professor of water and environmental engineering at the University of Birmingham, visiting professor at the Chinese Academy of Sciences, and runs his own strategic consultancy.

The new co-editors are committed to the continued development of the journal as a forum for research and practice that encompasses a wide range of disciplines and authors from across the globe.

Kristin Vogel, Henning Rust, Axel Bronstert, Heidi Kreibich, Bruno Merz and Annegret H Thieken

4. “Can hydrological models assess the impact of natural flood management in groundwaterdominated catchments?” by Hèou Maléki Badjana, Hannah L Cloke, Anne Verhoef, Stefan Julich, Carla Camargos, Sarah Collins, David M J Macdonald, Patrick C McGuire and Joanna Clark

The editors considered the 76 papers published in the four regular issues of Volume 16.

Nigel Wright David Proverbs

COME RAIN OR SHINE

CIWEM policy director Alastair Chisholm on how a national rainwater management strategy could reimagine approaches to rain

THE RHYTHMIC DRUMMING of rain on our roofs and pavements has long been a familiar soundscape of the United Kingdom.

Yet our approach to managing this ubiquitous element has remained stubbornly fragmented, often viewing it as either a nuisance to be drained away or a resource considered only within the confines of centralised water management

plans. This siloed perspective is no longer fit for purpose in an era defined by increasing climate volatility and mounting pressures on our water infrastructure. It’s time for a paradigm shift: a national rainwater management strategy that recognises the inherent potential of rainwater as both a valuable resource and a crucial element in mitigating flood risk, managed effectively right where it falls.

ASSET OR LIABILITY?

Currently, national strategies treat rain disparately: it is considered an asset in water resource management and a liability in flood risk management. This segregation leads to inefficiencies and missed opportunities, focusing on centralised assets and responsibilities rather than embracing a distributed and local approach.

The consequences of this binary approach are becoming increasingly apparent. We face the dual challenges of escalating surface water flood risk – with nearly 1.8 million properties at high risk by 2060, according to the latest assessment by the Environment Agency – and growing water stress, particularly in densely populated areas. The summer drought of 2022 starkly illustrated how

Capturing rainwater from rooftops can provide a reliable source of water for non-potable uses

rapidly the UK can move from relative water comfort to significant pressure.

The traditional response to managing surface water runoff has relied heavily on directing it into combined sewer systems, a practice that exacerbates the issue of storm overflow discharges and strains the capacity of our wastewater treatment infrastructure.

The current planning-led approach to encouraging SuDS has proven inadequate

When sewer capacity is challenged, the current approach often involves constructing large, energy-intensive storage tanks, a symptomatic ‘end-ofpipe’ solution that fails to address the root cause. This reliance on centralised, grey infrastructure is not only environmentally costly but also overlooks the significant potential of managing rainwater at its source.

SUSTAINABLE DRAINAGE: THE ENABLER

A more sustainable and forwardthinking approach lies in embracing the principles of sustainable drainage systems (SuDS). These encompass a wide array of techniques designed to capture, store, infiltrate, attenuate and convey surface water runoff in a way that mimics natural processes.

These nature-based solutions, ranging from swales and filter strips to permeable pavements and green roofs, offer a multitude of benefits beyond just drainage. They can enhance water quality through natural filtration, mitigate the urban heat island effect, and provide valuable amenity and biodiversity benefits. SuDS are often designed to handle significant rainfall events, offering a considerable capacity improvement over traditional highway drainage that is designed to manage rainfall events with a return period of every year or two at most.

However, the widespread adoption of SuDS at the requisite scale continues to face hurdles. While the still uncommenced Schedule 3 to the Flood and Water Management Act 2010 aimed to mandate SuDS in new development and remove the automatic right to connect surface water to public sewers, the

direction for delivery remains uncertain under this government.

The current planning-led approach to encouraging SuDS has proven inadequate, suffering from inconsistent design and delivery, and a lack of clear mechanisms for adoption and long-term maintenance (see ‘To have and to hold’, pp. 24-26). Even apparent rules within the planning system, like the National Planning Policy Framework, are open to interpretation by planners. This creates an adversarial environment where planning conditions and decisions are often challenged, causing delay and public expense.

This deficiency means new developments are often contributing unnecessarily to flood risk because they are insufficiently resilient, and are placing additional burden on water companies’ drainage infrastructure. Meanwhile, developers increasingly express a willingness to work with more of a rules-based approach, provided it is proportionate and enables seeking clarity and a consistent approach nationwide.

RAINWATER HARVESTING

Alongside SuDS, rainwater harvesting and reuse present a vital opportunity to unlock the resource potential of rainfall. Capturing rainwater from rooftops and stormwater from hard surfaces can provide a reliable source of water for nonpotable uses such as garden watering, toilet flushing and washing machines, and achieve significant reductions in per capita water consumption.

Furthermore, rainwater harvesting tanks can also provide crucial stormwater attenuation, especially when equipped with smart technology that allows for proactive drawdown in anticipation of rainfall events. A ‘smart SuDS’ approach can effectively bridge the gap between water resource management and flood risk mitigation at the property and development scale. But even non-smart rainwater tanks frequently used for toilet flushing will have spare capacity to store stormwater most of the time.

REGULATORY REVIEW NEEDED

Despite the clear benefits, the widespread implementation of rainwater harvesting and reuse is hampered by outdated regulations and guidance. The legal definition of “wholesome water”

in the Water Industry Act 1991 currently prevents statutory water companies from providing or adopting domestic water reuse schemes for non-potable purposes. This regulatory barrier should be urgently reviewed and updated to enable more ambitious water efficiency standards and unlock the potential of rainwater reuse. Revising Part G of the Building Regulations to require more efficient fixtures and fittings and to include an optional standard necessitating water reuse for toilet flushing would drive significant progress. Then, of course, we need clarity over whether the government is going to drive delivery of consistent quality SuDS with a clear mechanism for adoption and maintenance, either through Schedule 3, the planning system or some third way.

NATIONAL RAINWATER MANAGEMENT STRATEGY

To truly transform our approach to rainwater management, we need a national rainwater management strategy. This must better integrate development planning and regulation with wider water management planning and delivery. It will require collaboration across government departments, regulators, risk management authorities and local authorities. Key components of the strategy should include the following measures.

Rainwater harvesting and reuse present a vital opportunity to unlock the potential of rainfall

Introducing a mandatory framework for SuDS in new developments, setting clear standards for design, delivery, adoption and maintenance. This could involve implementing Schedule 3 or exploring alternative, streamlined mandatory mechanisms that learn from the experience in Wales and potentially leverage existing frameworks for highway adoption and surface water drainage charges. But it must be mandatory. The strategy will also need to make the right to connect surface water to the public sewer system conditional on first having maximised SuDS options. This fundamental shift will incentivise onsite rainwater management and reduce the burden on combined sewers. Any strategy should ensure that approval

and adoption mechanisms apply equally to both new development and retrofitted SuDS. If we’re going to have a mechanism for new development it should also work for the ongoing maintenance of retrofit SuDS.

We should also be actively encouraging the integration of smart SuDS technology, such as smart rainwater harvesting tanks, within wider SuDS approaches through updated guidance and standards. Doing so will help maximise the dual benefits of water resource management and stormwater attenuation.

We’ll need to update the legal definition of “wholesome water” to enable the widespread adoption of non-potable water reuse in homes by statutory water companies.

And finally, Part G of the Building Regulations must be revised to mandate more ambitious water efficiency standards and to encourage rainwater harvesting and greywater reuse.

By embracing a national rainwater management strategy, we can move away from treating rainwater as a mere waste product to be disposed of and instead recognise its potential as a valuable resource and a vital component of a resilient and sustainable water future. Managing rainwater where it falls is not just a drainage solution; it’s an opportunity to enhance water security, reduce flood risk, improve water quality and create more liveable communities. The time to reimagine rain is now. o

For more information on rainwater harvesting as part of Enabling Water Smart Communities, visit ewsc.org.uk

CIWEM CONVERSATIONS

NOW YOU’RE TALKING

CIWEM fellow Fola Ogunyoye and graduate member Rebecca Wardle come together to discuss mentoring, hybrid working and the joys of conference chitchat

FOLA OGUNYOYE IS director at TJAY Consultancy, specialising in flood and coastal risk management and resilience. He’s been in the industry for nearly 35 years, having worked as a contractor, researcher and in operational management before moving into consultancy 26 years ago, the past four years of which he has spent running his own business. He became a fellow of CIWEM in 2010.

Rebecca Wardle is a flood and coastal risk management advisor at the Environment Agency (EA), working with risk management authorities like drainage boards and local authorities to help them manage and deliver their flood defence projects and strategies. She has worked in the sector for around two years, having previously been employed as a project manager in construction. Rebecca joined CIWEM as a graduate member in 2024.

They met at the EA’s office in Kettering, Northamptonshire in February 2025, where they began discussing how support in career progression today compares with when Fola started out in the sector…

RW: There are clear steps in the EA, as an organisation, but I also think you make your own luck. If you want it, go get it. I try and get involved as much as I can because that’s how you learn what else is out there.

FO: When I was at the EA, more than 20 years ago, very few people were chartered with CIWEM. When I looked within my hierarchy, the first person I found who was chartered was the regional general manager – the number one person in the whole region – so that was quite a challenge. I contacted CIWEM and did it on my own, which was not easy, but then I was able to get one or two people to look over what I was doing and it was as a result of that that I got chartered in 1996.

When I started at Posford Duvivier (now Royal HaskoningDHV) in 1998, I got involved as a mentor straight away because I knew what it meant not to have one, and eventually took on the role of supervising mentor for the graduate scheme. I was always able to tell my story to young graduates, which encouraged them to properly engineer their journey under mentors who can support them. But it’s definitely a two-way benefit –sometimes I think I gain more than I give. I get so much from the enthusiasm, the bright ideas, and working with someone who’s trying to forge their path.

Mentoring is definitely a two-way benefit – sometimes I think I gain more than I give

RW: I’ve had a couple of official mentors but there are also people who probably do fulfil that role, but it’s not labelled as such. They’ve perhaps come up against the same barriers that I have, and they can help by talking through them. That more informal route works better for me, but others might prefer a more defined setup. Working as a team also naturally provides mentorship. Today is our team’s office day so we’re all bouncing ideas off each other – if you’re doing something you’ve not done before but someone else has, you go and speak to them.

FO: When I was junior and working more in offices, there were a lot of principals around – you’re seeing what they’re doing, you’re engaging with and learning from them. You can’t put a value on that, the impact is huge. After a while, of course, I became the person that people came to. Comparing that to now, post-Covid, where people are having less of that sort of interaction, there’s a lot that’s missing. But if you’ve never been in that situation, you don’t know that you’re missing it.

Garden watering is one potential use for harvested rainwater

RW: In this role I’m predominately working from home, but we do come in regularly as a team and prioritise that. For me, I live over an hour’s drive from here, so would I have taken this job if I couldn’t work from home? Probably not. That’s a massive positive of flexible working, in that you can get the right people for the job, and location doesn’t matter as much.

There’s a lot to be said for being in the office around other people – but there’s also a lot of distraction that comes with that. I get in touch with people on Teams to ask them things. If you’re willing to do that, I don’t think it’s the same as being in the office, but it’s close enough and it’s almost more focused.

I wouldn’t apply for a job that didn’t let me work from home because it’s about

that work/life balance as well. I’m so much less tired because I’m not spending two hours in the car every day. It’s all about flexibility though – empowering people to make the right choice for them but have the responsibility to make the right choice for the business as well.

FO: These days, now that I work mostly from home, I take every opportunity to attend meetings in person because I need to see other human beings.

RW: I know what you mean. For me, it’s the informal chitchat and things you can get involved in, hands on. The EA had our Minecraft game, RiverCraft, at last year’s Flood & Coast conference, for example. Also, you can get into surprising conversations where you

PLANET POSSIBLE

broaden your sectoral experience. Seeing people in person who are passionate about things, it draws you into topics you might not even know existed.

FO: Conferences are a really good, inexpensive way to bring new knowledge and training to people, especially those at the start of their careers. When I was running a team I would always try to get my graduates to CIWEM’s Rivers and Coastal Group conference because they would really get a lot out of it. I’m attending this year’s Rivers and Coastal Group Conference in fact – it’s just a great opportunity to engage. o

Join the CIWEM Member Platform and find a mentor or mentee at ciwem.org/ membership/mentoring

EACH MONTH ON CIWEM’s Planet Possible and MiniPod podcasts, host Niki Roach tells the stories of the people paving the way for positive planetary and societal change. May’s main episode is on pharmaceuticals, with Baroness Natalie Bennett, former leader of the Green Party, plus there’s a May audio special featuring a discussion of the 2025 winners of the Ofwat Innovation Fund. Each month we publish an edited excerpt of the latest episode of Planet Possible on the CIWEM website. Sign up to our digital newsletter to receive it direct to your inbox on the last Thursday of the month. Find Planet Possible in all the usual places, including Apple Podcasts, Google Podcasts and Spotify. Or visit planetpossible.simplecast.com

Fola Ogunyoye and Rebecca Wardle

Scenario Testing and Decision Support

Collaborative Platform – Land managers, engineers and ecologists easily access and contribute to the data, sharing insights leading to more sustainable river management practices.

Visual Superiority – Provides a transformational change to the way projects are presented to stakeholders, providing more confidence of predicted outcomes, and increasing the likelihood of design implementation.

For case studies and more visit www.storm-geomatics.com or call Mike Hopkins on 01608 664910

We have been providing safe access over water for more than 20 years. Our pontoon hire service facilitates works in the civils, construction and utilities sectors. We will support you with: Pumping

Hand Placed Concrete Bagwork MSE Soil Filled Bagwork

Biodegradable bags and liners enabling the hand placement of concrete in and around watercourses.

The real savings are not in material costs, but in the time saved in having a ready-toinstall product, and not having to dewater the watercourse to place the bagwork.

more information... T 01629 818450

SoluForm MSE Bagwork is supplied pre-filled with a high quality sand rich topsoil, supplied in a form that is ready to use and assemble on site once it arrives.

It aims to establish and promote vegetation growth on, and inside the bagwork, giving the bagwork structure an improved appearance.

BRAVE NEW WORLD

CIWEM president Hannah Burgess FCIWEM reflects on 22 years in flood and coastal erosion risk management

I JOINED THE flood and coastal erosion risk management (FCERM) industry in 2003, a geographer fresh out of university. So much has changed over these two decades, as climate change bites and our approach to assessing flood risk evolves to include multiple sources.

The biggest change I’ve observed has been a growing recognition of the scale of surface water flood risk. The latest statistics from the Environment Agency tell us that in England alone, 4.6 million properties are at risk of flooding from this source. Greater understanding and action to manage multiple sources of flooding was driven by the floods of summer 2007, where thousands of properties were affected by surface water flooding. Recently, there’s been an increasing focus on schemes that tackle more than one flooding source, driven by the partnership working between flood management organisations set out in the Flood and Water Management Act for England and Wales and in similar legislation elsewhere in the UK.

AN END TO SILOES

There has also been a growing recognition of the need to work across sectors and break out of silos to design places that better manage flood risk and coastal change. That will mean working with land use planners and major infrastructure providers but let’s be clear – engineered FCERM schemes alone cannot solve these challenges.

The increasingly rapid adoption of new technology is enabling decision making that relies on digital representations of our river systems and coastlines. We’ve gone from one-dimensional river models to integrated catchment models that can read real-time data and run hundreds of ‘what if’ scenarios.

There is also an increasing urgency to manage flood risk on a catchment basis. This is not a new concept but it is challenging to bring together decision

making on flood management, water resources and water quality, as well as environmental improvements. It is still the case, unfortunately, that multiple strategic plans, led by different parts of different organisations, drive catchment management in different directions. These silos are being broken down in some places, however, for example with ground-breaking projects like the Severn Valley Water Management scheme.

When it comes to adaptation, the situation on our coast is most acute

What has been most rewarding is seeing an increasingly diverse FCERM community that reflects the communities that we serve. It has been a while since I have been the only woman in a meeting, which was common at the start of my career. The establishment of initiatives such as Women in FCERM and WEM Pride mark great strides forward in diversity and inclusion, although there remains much to be done.

UNDERSTANDING RESILIENCE

Climate change is today’s problem to solve – we cannot simply kick the can down the road. If we do not adapt at pace now then our natural environment will respond in an unmanaged way to increasingly severe rainfall, rising sea levels and higher rates of coastal erosion. Communities will need support to adapt and become more resilient in light of climate change. How can the industry ensure this adaptation takes place?

We need to mainstream adaptation and resilience now, building on the many successful coastal and flood management pilots of the last 10-15 years and learning lessons where things didn’t work.

That means being clear on what we mean by resilience when it comes to working with communities – with being the operative word here.

Nor is it an action undertaken by one organisation. Resilience is a set of ongoing actions undertaken by a range of players, including residents and businesses, that ‘nibble away’ at a flood risk issue faster than the issue is aggravated by climate change. It’s residents making homes more resilient. It’s community flood action groups, supported by risk management authorities, to build the resources and attributes within a community that enable it to address its problems and improve its wellbeing. It’s planners trying to reduce flood risk to existing communities through new development. And it’s through combining multiple funding streams to tackle multiple sources of flooding through a range of capital and maintenance interventions. All of these should embrace technological advances such as AI where appropriate to maximise the efficiency and effectiveness of decision making.

ADAPTATION

Adaptation is often harder than resilience because it involves recognition that we cannot engineer our way out of climate change. The situation on our coast is most acute, with the latest analysis from the national assessment of flood and coastal erosion risk (NaFRA2) telling us that by 2105 over 10,000 properties will be at risk from coastal erosion (up from 3,500 today). In many places we will need to retreat in a managed way to avoid communities becoming blighted by this risk. As flood and coastal professionals, we must fight for those communities at risk. That means taking measured risks and innovating. We cannot stand still. We must rise to the challenge of climate change. o

HANNAH BURGESS

MY ROUTE TO CHARTERSHIP

PIERGIORGIO COSTA

Piergiorgio Costa MCIWEM C.WEM, a civil engineer and hydraulic modeller at Binnies, shares his route to becoming a chartered water and environmental manager

AS A CIVIL engineer and hydraulic modeller, I deliver flood risk studies and river restoration solutions using hydraulic modelling techniques to support the design. My role has also recently involved developing water resource management schemes. I’m really proud of my work as my expertise contributes to safeguarding communities, enhancing the environment and optimising water resources.

CHOOSING A CHARTERSHIP

I chose CIWEM because of my commitment to making a positive impact on the environment through my work and the alignment of the institution’s values with mine. I decided to become chartered early in my career as it was the best fit for my experience and my vision for career development. This decision reflects my dedication to sustainable practices and professional growth, ensuring that my work contributes to a healthier and more resilient environment. I became chartered in September 2023 after around a year spent doing the application process and preparing for the interview.

PREPARING

MY APPLICATION

Preparing my CIWEM application began with collecting information about the process and identifying gaps in my competencies. I then aligned my future career to address these gaps. Although achieving certain competencies was challenging due to the availability of certain types of work, such as projects at the detailed design stage, I found the process easier than I originally thought. I used the competency requirements to support my request to my employer to be involved in specific type of projects; in return they have always supported my needs and facilitated the achievement of certain skills. This journey has strengthened my abilities and prepared me for professional growth in water and environmental management.

Chartership forced me to expand my experience and link every piece of work to a broader context

Working with a mentor was crucial for my success, and I always recommend it to anyone starting this journey. I was extremely lucky as one of my colleagues volunteered to help and be my mentor. We are still in touch, and I’ll never thank him enough for the huge support. Given the positive impact of the mentoring process on me, I decided to become a mentor myself and am currently supporting two colleagues through the chartership process.

PREPARING FOR THE

PROFESSIONAL INTERVIEW

I used the competency report as a starting point to expand on each required competency. I then delved into the details of each one, defining all the drivers and regulations relevant to my work. This thorough approach ensured I was well-prepared, demonstrating

my comprehensive understanding and ability to apply these competencies effectively in my role.

On the day of the interview, I felt a bit anxious but very focused and excited. Unexpected IT issues occurred, causing the video call to malfunction. However, the interviewers were calm and kind, and after a few attempts, I managed to fix the issue. I received positive feedback on how I handled the situation, which boosted my confidence and showcased my problem-solving skills.

MY TOP TIPS FOR GETTING CHARTERED

1. Start with determination, set a target date and work consistently through a series of milestones leading up to the interview.

2. Find a good mentor: their support and guidance are incredibly useful throughout the process.

3. Use the chartership requirements as a guide and seek experience in a variety of fields to meet these comprehensively.

HOW HAS BEING CHARTERED BENEFITTED YOU?

Significantly! It forced me to expand my experience and link every piece of work to a broader context. I gained a deeper understanding of the main drivers and regulations relevant to my field, and I now have a clearer grasp of a project’s entire lifecycle, from concept to realisation. This comprehensive perspective has enhanced my professional capabilities and confidence.

NEXT STEPS

I aspire to become an engineering manager. I aim to apply my experience not only in flood risk management but also across various fields such as dams and irrigation plants. By expanding my expertise, I hope to help communities who suffer the critical issue of water scarcity. This ambition reflects my commitment to developing innovative solutions and contributing to sustainable water resource management. o

Want to become a chartered water and environmental manager? Find out more at ciwem.org/membership/ chartered-member

Partnering with

Whether your current focus is on talent development, driving innovative sustainability solutions, information sharing or expanding revenue streams, CIWEM can help support your organisational goals. We build a personal and bespoke relationship with each partner to achieve our common goals with 3 main areas of focus:

Get in touch with us and we’ll talk you through our three partnership levels and help you choose the right one for you.

Barbara Orth | Head of Partnerships

+44 (0)20 7269 5828

SUPPLIER AND INSTALLER OF FLOOD DEFENCE SYSTEMS

Lakeside Flood Solutions 01792 561117

sales@lakesidefloodsolutions.co.uk www.lakesidefloodsolutions.co.uk

PROPERTY FLOOD

RESILIENCE MANAGEMENT AND SOLUTION PROVIDERS

Watertight 0800 093 3463 enquiries@watertightinternational.com www.watertightint.com

DELIVERING SUCCESS

HYDROLOGY & ENVIRONMENTAL SCIENCE TRAINING COURSES

UK Centre for Ecology & Hydrology +44 (0)1491 838800

UKCEHtraining@ceh.ac.uk www.ceh.ac.uk/training

UKCEH, Maclean Building, Crowmarsh Gifford, Wallingford, Oxfordshire OX10 8BB

MANUFACTURER OF FLOOD RESILIENCE PRODUCT GreenBlue Urban Ltd 01580 830800 hello@greenblue.com greenblue.com

Northpoint, Compass Park, Bodiam, East Sussex TN32 5BS

TO ADVERTISE YOUR PRODUCT AND SERVICES HERE TO 11,000 CIWEM MEMBERS PLEASE CONTACT LEE MORRIS ON 0203 900 0102 OR EMAIL CIWEM@SYONMEDIA.COM

As a trusted UK water and wastewater technology manufacturer with a strong civils support team, Marsh Civils can help you and your team deliver project success.

Environmental Land Management Solutions Limited

Environmental contracting peatland specialists

www.marshcivils.co.uk

ICS Consulting provide innovative and leading-edge solutions to our clients. Our tools and processes are at the forefront of investment decision making and are used by companies operating in an asset rich environment where balancing cost, risk and performance is challenging. We develop end to end solutions, integrating customer and stakeholder needs with asset understanding to enable our clients to produce balanced, well-evidenced investment and delivery plans. Our multi-disciplinary team includes economists, market researchers, asset managers, engineers, IT developers and data modellers / analysts. +44 (0) 1977 621188 info@icsconsulting.co.uk www.icsconsulting.co.uk

Tetra Tech is home to industryleading scientists and engineers who are Leading with Science® to develop holistic and integrated solutions that evaluate, manage and protect water resources. Tetra Tech leverages industry-leading technical expertise, in-depth local knowledge, and sustainable approaches to provide resilient water futures for our clients. +44 (0) 113 278 7111 tetratech.com

To ensure your company is

A DAY IN THE LIFE OF AN...

ENVIRONMENTAL CONSULTANT

Jessica Knaggs MCIWEM tells us about a typical day as an environmental consultant at the engineering consultancy Arcadis

JESSICA KNAGGS HAS worked in the water and environmental sector since 2020. She joined the graduate scheme at Arcadis in late 2021 and has been in her current role for two years.

TELL US ABOUT YOUR ROLE

My role is to support clients in understanding and fulfilling their environmental requirements and helping them secure and deliver projects. All the while informing the design to champion environmental best practice. This can include supporting the coordination of environmental impact assessments for large projects or completing surveys to understand how proposed developments will impact watercourses and what can be done to mitigate negative impacts.

I have established a multi-disciplinary geomorphological working group at Arcadis to raise the profile of geomorphology – the study of landforms and landform evolution, in particular hydrogeomorphology which looks at the relationships between rivers and the landscape – and share knowledge and upcoming opportunities on this topic.

As part of this I have given presentations to various teams at Arcadis to introduce geomorphology as it is quite a niche area of environmental management.

WHAT DOES A TYPICAL DAY LOOK LIKE?

The start to my normal day is commuting, sometimes walking along the paths next to the River Ouse – if it is not flooded! I am able to work flexibly and I like to go into the office around four days a week. I enjoy working around other people as I feel more focused, achieve more and have the opportunity to engage with colleagues to talk about their project work, which is interesting as they mostly sit within different teams.

A typical day for me consists of a couple of meetings and some report writing, or design discussions with different technical teams. I try to attend

our internal community of practice meetings on water management or environmental impact assessments where I can build my knowledge of industry best practice. I also value opportunities to learn about other Arcadis project work.

WHAT SKILLS DOES THE JOB REQUIRE?

I love making an impact through my project work

The main skills I use on a daily basis are time management, communication (both in person and virtual) and presentation. It is also useful to be a problem solver and a creative thinker because some problems require innovative solutions. You also need a good understanding of environmental management and a willingness to continue learning by taking on different project roles. Also, be prepared to get stuck in and try something out of your comfort zone – part of being an environmental consultant is being adaptable and comfortable with learning in a new role.

WHAT DO YOU LOVE ABOUT WHAT YOU DO?

I love making an impact through my project work and feeling like I am improving quality of life for people. I also really enjoy working with likeminded people and being able to gain more knowledge on topics I am interested in through webinars and workshops, conferences and varied project work.

TELL US ABOUT A PROJECT YOU HAVE BEEN WORKING ON RECENTLY

I recently worked on a project to complete a hydrogeomorphology assessment for a UK local authority. This included a desk-based assessment and hydrogeomorphology survey to understand how a change in the floodplain infrastructure may impact the river. The river at the site is very active

and has evidence of a changing river shape over the past 100 years. However, in its current alignment the watercourse is confined by roads, rail and natural topographic features. Through the hydrogeomorphology assessment I was able to understand the natural processes (including erosion, deposition and transportation) occurring in this watercourse and identify opportunities to allow the river to become more natural.

ARE THERE ANY CHALLENGES THAT AFFECT YOUR WORK?

There can be a challenge around getting people to understand how important environmental management is and seeing it as an essential part of a project, rather than a last-minute addition.

HOW DO YOU BENEFIT FROM YOUR MEMBERSHIP OF CIWEM?

I often attend CIWEM’s webinars, take part in panel discussions and go to inperson events, gaining more knowledge on water management as a result. I’ve also been able to test out my public speaking skills which has allowed me to grow in confidence in my role. o

Become a member of CIWEM to access a wide range of webinars and other learning events. Visit ciwem.org/membership

TIME TO SKILL

Darren Eckford, CIWEM’s director of learning and organisational development, on the

exciting developments at this year’s Flood & Coast conference in Telford

THE FLOOD & Coast conference is a space for challenge and progress. It’s where we grapple with the big questions, exchange ideas and, crucially, share solutions.

This year we’re giving attendees more flexibility to shape their own learning experience. Alongside our headline programme – which takes on the sector’s most pressing challenges and opportunities – we’re introducing two new themed stages: one focused on technical skills, the other on critical people skills. Whether you’re deepening your understanding of property flood resilience installation, brushing up on adaptive pathways or exploring how to lead high-performing teams, this is about helping every attendee build the knowledge they need, for when they need it. No matter your role or level of experience, these sessions offer something to stretch and support you.

TOWARDS CONSTRUCTIVE DELIVERY

It’s part of a broader shift in tone – one that I’m particularly excited about. For too long, conversations in our sector have been dominated by constraints and caveats. But that’s changing. Flood & Coast 2025 is all about enabling action – equipping professionals with the tools, knowledge and confidence to shape sustainable outcomes for the communities they serve. It’s a move from cautious debate to constructive delivery.

That principle of empowerment also underpins the new approach we’re taking for early career professionals. Instead of a standalone stage, we’re launching a daily welcome session for early careers attendees – giving them a clear route into the programme and a helping hand in navigating the event.

We all remember what it felt like to walk into our first industry conference. This is

about removing the barriers, offering guidance and integrating early careers professionals into the wider event in a way that feels inclusive and meaningful.

Inclusivity is also central to another exciting development: our new local authority zone. We know that local government initiatives deliver half of all flood and coastal capital investment – yet they’re often underrepresented at events like this. By giving councils free space to exhibit their work, we’re creating a platform to showcase their projects, share insights and connect with partners. It’s an important recognition of the role they play – and a tangible step towards greater collaboration across the sector.

GOODBYE TO TELFORD

And, of course, this year’s conference marks something else: our final time hosting Flood & Coast in Telford. It’s been a fantastic venue and the event has flourished here, but we’re ready for the next chapter. In 2026, we move to Liverpool – to a city-centre location that opens up all sorts of opportunities for engagement, accessibility and growth.

Flood & Coast 2025 is all about enabling action

Liverpool City Council has already shown extraordinary support, including a £30,000 contribution to help us bring the event to the northwest. Their enthusiasm matches ours, and we’re working closely with them on new outreach ideas – from hosting a ‘communities morning’ where those affected by flooding can access expert advice, to building in site visits so that delegates can see frontline innovation for themselves.

Personally, I’m thrilled with the direction we’re heading. This past year has been one of energy, optimism and ambition – and I see that reflected in every part of Flood & Coast 2025. It’s an event that listens, adapts and leads. I’m proud of what we’ve achieved – and even more excited about what comes next. I look forward to seeing many of you there. o

Flood & Coast 2025 opens on 3 June. For tickets, visit floodandcoast.com

A workshop at Flood & Coast 2024

CIWEM

Using grey solutions to support blue-green infrastructure

Helping to make urban climate resilience a reality

By supporting ‘green by default’ best practice and complementing it with engineered grey infrastructure, we are helping to pioneer eﬀ ective hybrid water management solutions that can:

• reduce the urban heat island eﬀ ect

• boost biodiversity

• increase water circularity

• create amenity value

We work closely with our partners to create smart solutions including tree tanks, blue-green roofs, irrigation, rainwater attenuation and inﬁ ltration tanks.

See how we could help develop your hybrid water management solutions for a more climate-resilient future.

Scan to learn more

We are at Flood & Coast 2025

Stop by Stand E37 and learn how our Leading with Science® approach to complex water issues empowers organisations through resilient long-term solutions in flood risk and coastal erosion.