Page 118 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads

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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
species is an important aspect of designing
achieve the following:
character, particularly where SuDS are being
SuDS systems and features. Vegetation is an
applied to a greenfield site. Naturalistic
■
General planting design should connect
inherent functional part of any soft-landscape
planting is usually the most appropriate,
with the SuDS landscape, ideally with
SuDS feature as well as being about
providing maximum biodiversity benefits as
grassland, woodland or ornamental
aesthetics, usability and wildlife benefits.
well as being cost effective, resilient and
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.

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