Page 119 - Newham SuDS DESIGN & EVALUATION GUIDE
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Detailed Design  9.10 Planting design for SuDS  9.10.2 The Principles of SuDS planting selection & design         Detailed Design


 The choice of vegetation cover and plant
                                                             SuDS planting is often naturalistic in
      SuDS vegetation choice and design should
                                                             character, particularly where SuDS are being
      achieve the following:
 species is an important aspect of designing
 SuDS systems and features.  Vegetation is an
                                                             applied to a greenfield site. Naturalistic
         ■
          General planting design should connect
                                                             planting is usually the most appropriate,
 inherent functional part of any soft-landscape
          with the SuDS landscape, ideally with
 SuDS feature as well as being about
                                                             providing maximum biodiversity benefits as
          grassland, woodland or ornamental
                                                             well as being cost effective, resilient and
 aesthetics, usability and wildlife benefits.
 Vegetation type and species selection can
          benefit and biodiversity. The design
                                                             maintenance requirements.
 significantly affect hydraulic and pollution
          criteria set out in the Biodiversity section
 control functionality as well as the   planting creating linkages for visual   most likely to have modest long term
          (9.9) should be followed where                     In built up areas a more formal and
 contribution to amenity and biodiversity.
          appropriate.                                       ornamental design style may be required for
 The SuDS plant palette will often vary from     ■           raingardens, bio-retention features and green
 conventional landscape design for reasons of   Vegetation should permanently cover the   / blue roof surfaces. Recent research by the
          ground, both in summer and winter, to
 SuDS functionality, different ground                        Royal Horticultural Society (RHS) has
 conditions and to protect the wider   prevent erosion of the soil surface.  demonstrated that ornamental plants, close
 environment from chemical contamination.    ■  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
 Strutts Centre, Belper.
 Contemporary ‘prarie’ planting in raingarden   filtering water and encouraging silt to   wildlife as native planting but the capital cost
 collecting roof runoff and access road runoff.  settle out in components like filter strips,   and management can be more difficult and
          swales and basins.                                 expensive.

 113     ■  A vigorous growth of vegetation,                 Contract arrangements should always allow             114
 9.10.1 Objectives of planting design for SuDS   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.
 SuDS planting design should satisfy general     ■  augmenting biodiversity by structure,
 planting design criteria and relies on an   species richness and careful management     ■  Planting design should avoid fertilizer,
 awareness of the landscape maintenance   (refer to the Biodiversity section 9.9)  pesticides or herbicides wherever possible
 requirements. In addition, planting should     ■  creating attractive surroundings and   to avoid leaching of chemicals into the
 fulfill specific SuDS functions, such as:  SuDS and groundwater. They should use
 community amenity  careful plant selection and a soil
   ■  preventing soil erosion
   ■  protection of the environment by avoiding   conditioner such as ‘green waste
   ■  trapping silt and pollution from runoff   the need for herbicides, pesticides or   compost’ as an alternative to suppress
 fertilizer treatment.  weed growth and improve soil fertility.
   ■  encouraging interception (evaporation,
 infiltration and transpiration)

   ■  enabling long term infiltration by opening
 soil profiles through the root growth cycle
                                 Strutts Centre, Belper.
             Brick channels collect roofwater for linear
                raingarden with garden style planting.


 London Borough of Newham SuDS D & E Guide                                                     © 2018 McCloy Consulting & Robert Bray Associates  London Borough of Newham SuDS D & E Guide                                                     © 2018 McCloy Consulting & Robert Bray Associates
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