Rain falling on buildings and hard surfaces cannot infiltrate into the ground so it needs to be drained artificially in order to prevent problems of localised flooding. The traditional method of dealing with surface water has been to pipe it away from developments and discharge it to the sewerage system or nearby watercourses. This has implications for water quality, the ecology and amenity of watercourses and downstream flooding.
Leeds City Council supports sustainable drainage systems which provide an alternative to the traditional approach. Sustainable drainage seeks to mimic more natural drainage processes by allowing rainfall to soak into the ground where possible or by delaying discharges. This reduces both the volume and rate of surface water runoff.
The background and principles of sustainable drainage in Leeds are covered by the existing Supplementary Planning Guidance No. 22 - Sustainable Drainage in Leeds
This guidance is available as a download on this page. Alternatively paper copies can be purchased for £10 (plus postage), or can be collected, from the Development Enquiry Centre, The Leonardo Building, 2 Rossington Street, Leeds LS2 8HD. Tel: 0113 247 8000 for further details.
General guidance for the management of surface water runoff has been outlined in council's 'Minimum Development Control Standards for Flood Risk'. For all sites, we will require a Flood Risk Assessment (Drainage Impact Assessment), which addresses the flood risk associated with the run-off generated by the proposed development.