Tackling SuDS in Cambridgeshire

The introduction of the Flood and Water Management Act and National Standards for sustainable drainage systems puts added pressure on councils to think about drainage. David Levin from AECOM, pictured, explains how they are helping Cambridgeshire CC tackle this new responsibility.

It has been a long road, but it seems sustainable drainage systems (SuDS) are finally gaining ground. With the introduction of the UK Flood and Water Management Act (2010), all new developments will be required to implement SuDS.

Reducing run-off rates, mitigating flood risk, recharging stressed water tables, and filtering polluted stormwater are all motivating factors for this change in legislation. Crucially, the Act removes the long-referenced road-block to SuDS - an active adoption body. The Act introduces the SuDs Approval Body (SAB), a role to be taken up by county and unitary authorities, who will be responsible for approving and in some cases, adopting and maintaining new SuDS schemes.

SuDS have the potential to become an integral part of the urban landscape. But they come with a health warning; if they aren’t given the care of design and maintenance that we would expect for any other part of the public realm, they won’t deliver the benefits. It seems obvious, but good design that successfully integrates water management with the urban world still seems to be a challenge.

Draft National Standards for Sustainable Drainage Systems were released in December 2011 and outline how Defra expects SuDS to be designed and adopted. No doubt the draft proposals will be finessed to provide consistent expectations and guidance for design, but crucially the National Standards remain focussed on functionality and leave the broader design considerations surrounding place-making, design quality, ecological value, and contextual response to be set out through local plans. This leaves the SAB and local authorities with a challenge - if they want to approve and adopt SuDS that respond to the local agenda and maximise value to communities, they need to embed that vision through local standards and skills.

Embracing a changing landscape

As with the introduction of many new policies, the draft National Standards and the proposed approval and adoption processes raise as many questions as they answer. Many authorities taking on the SAB role are uncertain how it will dovetail with existing processes and roles and are raising a number of questions:

• How will the SAB interact with the Local Planning Authority to ensure applications are assessed efficiently?
• Who will be included in the SAB, and when will it start operating?
• Where will funding for the SAB and SuDS maintenance be sourced in the long-term?
• How will all the various people involved in the process be trained in time?
• As it stands, the SuDS approval and adoption requirements could come into place as soon as October 2012, though Defra is considering an extension into 2013. Whatever the date, the coordination required means that both county and local authorities and their partners need to start testing local issues now while Defra refines the national guidance.

Cambridgeshire County Council has been one of the early movers, deciding that a pro-active approach is the only option. Cambridgeshire believes it can make the journey considerably easier by having the awareness, coordination and a clear vision established locally in advance.

“Given the uncertain timescales of the SAB commencement and the level of development that’s planned in Cambridgeshire, the County Council decided to take a proactive approach to SuDS. Working in partnership with key stakeholders including the Environment Agency and District Councils, the County Council is developing a handbook to promote the use of SuDS in new developments, and to provide support to local planning authorities before the SAB commencement. This handbook will be used as the local standards for SuDS in the county supported by the National Standards. In addition to detailing the local standards for SuDS in Cambridgeshire, the process of developing the handbook also helped raise awareness of the SAB duties, the associated implications, and reinforced on-going partnership working in flood risk management.” Sass Pledger, Flood and Water Manager, Cambridgeshire County Council

Development of Cambridgeshire’s SuDS handbook

Recognising the opportunity to proactively establish clear local standards, build relationships, and define internal processes early on, Cambridgeshire County commissioned AECOM to develop a SuDS handbook. Cambridgeshire receives the lowest rainfall in the UK, and water resources are limited, but conversely water is ever-present on the county’s surface as it has a generally flat topography, a high water table, and predominantly claysoil that makes it difficult for water to infiltrate. It is therefore unsurprising that the county has a long history of innovation in surface water management. In recent years, the area has continued to push the boundaries with the development of Cambridge City’s award-winning SuDS Design and Adoption Guide. Now, Cambridgeshire County’s handbook builds further on the knowledge developed in the area, and brings together local guidance on how stakeholders will work together and on how the SAB will expect SuDS design to respond to local expectations.

It was clear while developing the handbook that including Cambridgeshire-specific standards would be essential to make the National Standards meaningful locally. As part of the process, 20 local SuDS standards were created and refined. These clearly communicate the local design considerations developers need to address when working in the county. Not only does this enshrine good design into local policy, but it also makes development in the county more attractive to developers, as it removes ambiguity regarding the types of acceptable drainage.

Solving problems together

While the National Standards and the handbook will provide crucial guidance and examples of good practice, Cambridgeshire also realised that half the challenge comes in communication and coordination. In developing the contents of the handbook, a series of workshops was held to raise awareness, establish local priorities and secure agreement on how the approval and adoption process will be handled. Establishing understanding and support from the local authorities in the county has been crucial, not only because of their role as the intermediary in handling and enforcing SuDS requirements alongside planning approvals, but in the local knowledge and expertise their staff can bring to the process. Sharing staff expertise in drainage, maintenance, ecology and urban design will be crucial to delivering quality SuDS.

“Successful SuDS are dependent on many disciplines in different organisations coming together; communication and joint working are key to this. This promotes consistency, and opportunities can be realised from perceived constraints leading to more efficient, cost-effective processes and better places for people to live and work.” Simon Bunn, Sustainable Drainage Engineer, Cambridge City Council

Through stakeholder collaboration, checklists were created for the handbook that the SAB will use at various stages of approval and adoption. Four checklists outline the documentation and evidence the SAB will be seeking for design approval, construction verification, maintenance specifications, and asset transfer. While the checklists have been created for the SAB, they will benefit other stakeholders looking for insight into SuDS criteria the SAB is looking for.

In the age of localism, it is unlikely national policy will provide all the answers, and it will be crucial for county and local authorities to outline their own priorities and ensure they can be delivered locally. Cambridgeshire hopes to capitalise on the benefits SuDS can bring to the area, seeing this as both a challenge and an opportunity.

David Levin, Sustainability Consultant, Europe, AECOM