Page 120 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads
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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          ■
           of wetlands and ponds. Grass surfaces will                Amenity Grass - for everyday community                     ■  Amenity grass is usually mown at 35-
                                                                     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.


           Newham Council SuDS D & E Guide                                                                        © 2020 McCloy Consulting & Robert Bray Associates  Newham Council SuDS D & E Guide                                                                        © 2020 McCloy Consulting & Robert Bray Associates
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