PPS 15 Planning and Flood Risk (Revised)·Page 45·6.52
Watercourse integration in residential development
Watercourses should be incorporated into open space requirements for new residential development rather than located to the rear of properties. Removal of culverts and re-introduction of natural watercourses should be encouraged where possible.
Consistent with the requirements of PPS 7 'Quality Residential Environments'; incorporating watercourses into the open space requirements for new residential development will be preferred to locating them to the rear of properties where they are difficult to maintain or can become dumping grounds contributing to flood risk. Where possible the removal of culverts and the re-introduction of the natural watercourse should be encouraged.
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/regional/PPS 15 - Planning and Flood Risk (Revised).pdf