Part One: Spatial Strategy and Policies (Regulation 19)
Sustainable drainage and surface water management (SuDS)
Policy DLP46 Sustainable drainage and surface water management (SuDS)
- All new developments should incorporate SuDS and all development proposals should provide details of adoption, ongoing maintenance, and management of SuDS.
- SuDS shall be designed in line with the Black Country Local Standards for SuDS. Preference will be given to systems that contribute to the conservation and enhancement of biodiversity and green infrastructure in the wider area.
- For all major developments, surface water flows must be reduced back to equivalent greenfield rates. If greenfield runoff rates are not considered to be feasible for viability or other reasons, then the developer must submit evidence demonstrating what the constraints to achieving this are and how their development will accommodate runoff rates that are as close as reasonably possible to greenfield rates.
- Under no circumstances will post-development runoff rates that are greater than pre-development runoff rates be permitted.
- New developments shall demonstrate that all surface water discharges have been carried out in accordance with the principles laid out within the drainage hierarchy, whereby a discharge to the public sewerage system is avoided where possible.
- Surface water drainage strategies are required for all major developments, regardless of their size and the flood zone and catchment they are in to meet the requirements of the Lead Local Flood Authority (LLFA). These should take into account all sources of flooding to ensure that future development is resilient to flood risk and does not increase flood risk elsewhere and should look to provide wider betterment.
- A hydrogeological risk assessment is required where infiltration SuDS are proposed for anything other than clean roof drainage in a Source Protection Zone 1.
Justification
12.53. The incorporation of Sustainable Drainage Systems (SuDS) into new developments helps to manage and minimise surface water. SuDS generally are landscaped facilities such as wetlands, retention ponds, soakaways, swales and/or permeable surfaces, the primary function being to reduce the volume and peak rates of water run-off from new development, but they should also fulfil their potential to provide new wildlife habitats and amenity spaces into developments, they should be multifunctional.
12.54. SuDS can also improve water quality by increasing the filtration of pollutants, and thereby helping to support the objectives of the Water Framework Directive. They allow the management of diffuse pollution generated in urban areas by treating water and reducing the level of pollutants that enter rivers and other watercourses therefore resulting in less wastewater requiring treatment. Good SuDS design can be key for creating a strong sense of place and pride in the community for where people live, work and visit, making the surface water management features an integrated part of the development.
12.55. All schemes with the inclusion of SuDS should demonstrate they have considered all four areas of good SuDS design: quantity, quality, amenity and biodiversity. Completed SuDS schemes should be accompanied by a maintenance schedule detailing maintenance boundaries, responsible parties and arrangements to ensure the SuDS are managed in perpetuity.
Evidence
- Black Country Level 1 Strategic Flood Risk Assessment (SFRA) 2021
- Dudley MBC Level 1 Strategic Flood Risk Assessment (SFRA) 2024
- • Black Country Water Cycle Study Stage 1 2020
- Dudley MBC Water Cycle Study Stage 2 2024
Delivery
- Through Development Management and LLFA processes
