Afforestation is the process of planting trees, either to replace those removed during forest harvesting or as a means of land use conversion. Afforestation is part of several natural water retention measures as it can contribute to a more natural and sustainable hydrologic cycle.

'Hard-edged' conveyance channels to move water between components in a SuDS 'train'.ﾠ Typically narrower than swales, but may also include vegetated aspects.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

Gently sloping vegetated strips of land that provide opportunities for slow conveyance and infiltration. Designed to accept runoff as overland flow from upstream and to slow the progress of this runoff.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission