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9.10.2 The Principles of SuDS planting selection & design


      SuDS vegetation choice and design should               SuDS planting is often naturalistic in
      achieve the following:                                 character, particularly where SuDS are being
                                                             applied to a greenfield site. Naturalistic
         ■  General planting design should connect                                                                 Detailed Design
                                                             planting is usually the most appropriate,
          with the SuDS landscape, ideally with              providing maximum biodiversity benefits as
          grassland, woodland or ornamental
                                                             well as being cost effective, resilient and
          planting creating linkages for visual              most likely to have modest long term
          benefit and biodiversity. The design
                                                             maintenance requirements.
          criteria set out in the Biodiversity section
          (9.9) should be followed where                     In built up areas a more formal and
          appropriate.                                       ornamental design style may be required for
                                                             raingardens, bio-retention features and green
         ■  Vegetation should permanently cover the

          ground, both in summer and winter, to              / blue roof surfaces. Recent research by the
                                                             Royal Horticultural Society (RHS) has
          prevent erosion of the soil surface.
                                                             demonstrated that ornamental plants, close
         ■  The matrix of roots, stems and leaves of         to the wild type, especially from the northern

          vegetation slows the flow of runoff,               hemisphere can provide similar benefits to
          filtering water and encouraging silt to            wildlife as native planting but the capital cost
          settle out in components like filter strips,       and management can be more difficult and
          swales and basins.                                 expensive.

         ■  A vigorous growth of vegetation,                 Contract arrangements should always allow             114
          particularly when forming an extensive             for additional or remedial works to ensure the
          root mat, encourages natural losses into           integrity of vegetation surfaces that perform
          the ground throughout rainfall events.             a SuDS function.

         ■  Planting design should avoid fertilizer,

          pesticides or herbicides wherever possible
          to avoid leaching of chemicals into the
          SuDS and groundwater. They should use
          careful plant selection and a soil
          conditioner such as ‘green waste
          compost’ as an alternative to suppress
          weed growth and improve soil fertility.








                                 Strutts Centre, Belper.
             Brick channels collect roofwater for linear
                raingarden with garden style planting.


      Enfield Council SuDS D & E Guide                                                                            © 2018 McCloy Consulting & Robert Bray Associates
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