Skip to content
channel, watercourse, drainage, nature, bach, forest, trees, stream, fall, drainage, drainage, drainage, drainage, drainage

In this episode of the Brookbanks Podcast hosted by Ben Wakeling, guests Paul Coombs, Senior Civils Engineer and Andrew Wilkinson, Director, share their experience and reflections on the evolving landscape of Sustainable Drainage Systems (SuDS).

Understanding SuDS: What, Why & Where

SuDS are designed to replicate natural drainage processes, offering a more sustainable alternative to traditional underground systems. Andrew encourages listeners to explore the evolving regulations such as the National Standards for SuDS (updated July 2025), and compares England’s position to the journey already travelled in Wales, with concepts such as SuDS Approval Bodies (SABS) being in place.

Guidance highlights how SuDS can deliver multiple benefits, improving water quality, enhancing amenity, and supporting biodiversity, while managing flood risk. Essentially, Engineers/Designers want to mimic nature in providing flood protection through use of SuDS, rather than defaulting to concrete or underground “traditional” drainage in order to provide multiple benefits to water quality and amenity and not just dealing with water volumes.

Commuted Sum Costing: A Persistent Challenge

One of the key barriers to SuDS adoption is the commuted sum, the financial value assigned to assets handed over for long-term maintenance. Paul notes that while designers have tools to cost schemes, inconsistent rates and under-utilisation of software often leave this task to commercial teams. He proposes the development of an online calculator to provide consistent, realistic values for SuDS assets, potentially linked to carbon costing tools to support sustainable decision-making.

Adoption & Maintenance: Bridging the Gap

SuDS offer clear benefits to communities and ecosystems, having well maintained watercourses that convey water through catchments allows for wildlife to flourish and improved water quality. But their maintenance requirements can be a sticking point. Traditional drainage systems are easily serviced with standard equipment, whereas SuDS features like swales require different approaches. This can create friction during design reviews, particularly with local authority highways teams accustomed to conventional methods. Education and greater adoption will make these challenges easier to face, as new tools and methods are used.

Looking Ahead: Industry Change & Innovation

While this podcast isn’t a comprehensive training session, it offers valuable insights into the practical realities of SuDS design and adoption. Paul and Andrew’s reflections underscore the need for innovation, collaboration, and consistency in how SuDS are implemented and maintained.

Top view of vibrant foliage and winding paths in a park in Curitiba, Brazil.

Listen Now!

Whether you’re a drainage engineer, developer, or simply interested in sustainable infrastructure, this episode offers practical insights and forward-thinking ideas from two of Brookbanks’ leading experts.

Members on the Podcast

Andrew Wilkinson, Director and Head of Wales Office at Brookbanks
Director

Andrew Wilkinson

Read Profile
Ben Wakeling, Head of Cost and Commercial at Brookbanks
Head of Cost and Commercial

Ben Wakeling

Read Profile
Senior Civil Engineer

Paul Coombs

Read Profile

More News

An aerial view of a Brookbanks construction site.

Brookbanks Webinar: De-risking Infrastructure Design

February 18, 2026

Earlier this month, we hosted a lunch-time webinar exploring how infrastructure design can be strengthened well before construction begins. Led by our Civil Engineering specialists Ryan Meade and Toby Crayden, the conversation focused on the practical steps that help to reduce uncertainty and make the transition from design to delivery smoother and more predictable. Their session looked at the real‑world challenges that commonly appear between early drawings and activity on site. Ryan and Toby shared their experience of how early awareness, clearer coordination and the right conversations at the right time can make a measurable difference to project outcomes.

Read More
A row of red brick houses with blue sky and a field in front of them.

Two Years On: Billions Still Sitting in Unspent Developer Contributions and What That Means for Developers

February 18, 2026

Two years after the Home Builders Federation (HBF) first highlighted the scale of unspent developer contributions, more than £8 billion in S106 and CIL remains unused across England and Wales, with a significant portion dormant for over five years. For developers, it raises a critical question: if infrastructure isn’t being delivered, are these obligations still proportionate or commercially justified? This article explores why the issue persists and how reviewing triggers, outdated requirements and opportunities for modification or claw-back can turn S106 from a fixed liability into an actively managed commercial tool that protects viability and unlocks value.

Read More