Page 121 - Newham SuDS DESIGN & EVALUATION GUIDE
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Detailed Design  9.10.3 SuDS vegetation types  Amenity grass                                                      Detailed Design

      An everyday grass surface that can be used
 There are a number of vegetation types
      in SuDS features allowing regular public use.
 commonly used in SuDS:
   ■
      The great advantage of amenity grass is its
 grass surfaces – a common SuDS ground
      availability as purpose grown turf and most
 cover
      of the time it will establish quickly if properly
   ■
 herbaceous planting - typically used in
      laid on ground that is not too wet. It will grow
 raingardens and bioretention
      well as bases of SuDS features that are
   ■
 wetland and pond planting – usually
      designed to be dry most of the time. It is
 based on native wetland habitats  on the dry shoulders of swales and basins as
      useful for providing a 1m wide cosmetic neat
   ■  trees and shrub planting – used to   edge to longer grass and as amenity green
 enhance the landscape and aid
      space for the community.
 interception losses
         ■  Amenity turf should be grown on a sandy
   ■  green / blue roofs – resilient low planting   loam to aid surface drainage.
 for shallow growing media on roofs.                                                   Parkside, Bromsgrove.
         ■  Seeding is a cheaper and more flexible            Amenity grass shallow detention basin feature,
 These are covered in the following sections.                integrated into site design, manages occasional
 Rectory Gardens Rainpark, Hornsey.  option but can fail easily in adverse
 Forebays, swales and underdrained basins use   conditions. Coir or jute matting is a         extreme rainfall.
 SuDS turf (100-150mm) to filter runoff, with   practical way to provide temporary
 amenity grass for public use.
          erosion protection.
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         ■  A mown edge of amenity grass is often
 9.10.3.1 Grass surfaces  important where SuDS grass and longer
          meadow grass is used to make it clear
 Grass is the most cost effective, flexible and   There are 3 general types of grass surfaces   that the longer grass is deliberate and to
 familiar surface for vegetated SuDS features   used in SuDS landscapes:  give a maintained appearance.
 like filter strips, swales, basins and the edges
   ■  Amenity Grass - for everyday community     ■  Amenity grass is usually mown at 35-
 of wetlands and ponds. Grass surfaces will
 use and to give a cared for appearance  50mm as this is the short-mown grass
 often merge seamlessly with the surrounding
 host landscape.    ■  SuDS Grass – a longer amenity grass used   preferred by many Councils and is familiar
          to the public. This short grass is
 where water may flow or be contained in
 Grass surfaces are reasonably easy to   susceptible to drought and does not
 temporary storage
 establish, simple to maintain, meet the most   provide the flow reduction and filtering
 important requirements in managing runoff     ■  Meadow Grassland - containing a mixture   required in SuDS.
 and can provide biodiversity and amenity   of grasses and flowering plants left long
 benefits.  with an annual cut towards the end of the   Design Note:

 year.    Avoid turf products with plastic mesh (unless they are bio-degradable) as these introduce
 Grass swards must be vigorous and able to
       microplastics to the environment.  Photo-degradable is not the same as bio-degradable as the
 repair themselves if damaged. For this, an
                                     plastic breaks down into microplastics.
 appropriate topsoil depth is necessary.


 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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