Page 121 - 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.

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