SRA Annual Report 2019-20: Guidance on Sustainable Drainage Systems (SuDS)
Activities in 2019-20
Somerset-specific guidance on Sustainable Drainage Systems (SuDS) is being produced to encourage the creation of high quality, multi-benefit, integrated SuDS at new sites across the county. This project is being led for Somerset Rivers Authority by Somerset County Council using contractors JBA Consulting. Work in 2019-20 has included surveys, workshops, and the preparation of draft Somerset Local Standards for new housing developments, commercial properties and community facilities. By law, new developments must not increase flood risks. They must also prepare for future climate change.
The draft Somerset Local Standards draw upon some of the problems identified and lessons learned through the Somerset SuDS Review. Between 2016 and 2018, 20 recently-built sites were inspected for the SRA by the county council, working closely with SRA partners and contractors JBA Consulting. Sites included big housing estates, retirement apartments, industrial units and offices, an arts centre, and a hotel and pub. In total, 438 elements of 113 SuDS features were inspected.
The draft Somerset Local Standards therefore cover issues such as water quantity, water quality, biodiversity and amenity.
They set out key principles and specify requirements.
Three brief examples: firstly, new developments in the Tone catchment must deal with higher flood risks from the River Tone.
Secondly, the question of who maintains SuDS has long concerned the Board of Somerset Rivers Authority and the public. Somerset Local Standards make it clear that planners expect to see a full maintenance and operational management schedule for the entire lifetime of a development.
Thirdly, the draft local standards spell out that SuDS should be integrated as part of landscape designs and made accessible for residents to enjoy. In practice this means creating more imaginative public spaces such as car parks and play and recreation areas, and offering people chances to boost their health and wellbeing through features such as paths for walking around SuDS.
The aim is to have detailed guidance finalised and agreed later this year for adoption by Somerset’s Local Planning Authorities. Some delays were caused in spring 2020 by the effects of the coronavirus pandemic.
A thorough and detailed Somerset SuDS website is also being created. This features far too many subjects to list here individually, but broadly they include:
- different elements of SuDS
- a detailed guide to the planning process for different kinds of developments, including the important pre-application stage
- design standards, design challenges, and local design considerations (with special attention paid to Internal Drainage Boards, district councils, and Exmoor National Park Authority)
- plus case studies, construction, inspection, operation and maintenance
A section for residents on Living with SuDS includes the opportunity to download a free copy of Simple SuDS for Local People, a very useful guide written by self-declared ‘floodies’ Teresa Bridgeman, who chairs West Somerset Flood Group, and Phiala Mehring of Reading University.
Take attenuation basins and underground storage facilities, for example
Across Somerset, attenuation basins and underground storage facilities are often used to hold water, but local SuDS could do much more. Well-designed SuDS should look, feel and operate like natural features within a landscape, and they should be easy and safe to maintain. A lot could be improved if people considered – and committed themselves to – integrating SuDS from the very earliest stages of site design. New SRA-funded SuDS guidance will help people to create well-designed schemes by outlining clear local requirements, promoting early engagement, and emphasising the multi-functional benefits that can be achieved.
Below are four examples of some Somerset attenuation basins and underground storage facilities.