Page 37 - Newham SuDS DESIGN & EVALUATION GUIDE

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Concept Design 7.4.2 Building the Management Train ■ Source Controls: green and blue roofs, 7.4.3 Collection of runoff from hard surfaces Concept Design

The way that runoff is collected from roofs,
A successful management train begins with
Surface collection in channels, gutters and
permeable surfaces, filter strips, protected
source control, and uses surface conveyance,
permeable pavements, or as sheet flow onto
roads, car parks and other hard surfaces is a
wherever possible, to link subsequent SuDS
critical consideration in any SuDS design.
grass surfaces, keeps runoff at or near the
filter drains, together with some swales
and basins, provide the first stage of
components in series. Integration of the
surface, enabling cost-effective and visually
Conventional drainage techniques such as
legible design.
treatment, intercepting primary pollution
management train should be considered from
gully pots and pipes, promote the
the Concept Design stage and throughout
and reducing runoff flow rates.
concentration of flows and mobilisation of
Collection of runoff at or near the surface
the design process.
be preceded by source controls, and meet
so that management of runoff at or near the
for simple removal of blockages.
The management train provides potential for
‘interception losses’ along its whole length, as ■ Site Controls: these features will normally pollutants, forcing runoff deep underground, also reduces maintenance costs, and allows
remaining storage requirements.
surface is difficult to achieve.
well as through soakage into the ground, Permeable surfaces will often store the
evaporation, and transpiration through the whole attenuation volume. Where the is
Highway runoff is intercepted using a chute
leaves of vegetation. It also reduces the rate insufficient storage at source, additional
gully and taken into a conveyance swale at this
at which runoff flows through the site, and open conveyance and storage structures, retrofit SuDS project. Devonshire Hill, Haringey.
provides treatment of runoff as it passes such as basins and protected wetlands or
through each SuDS component. ponds, will manage remaining runoff
volumes on most sites.
Selecting SuDS components within the
management train: ■ Regional Controls: where it is difficult to
store all the runoff within a development
boundary, clean water can be conveyed to
31 open storage features within public open 32
space or other parts of a development to
contribute to open space amenity.
Flow Controls can be incorporated in green Permeable paving and planted open channels
roofs to manage volumes and provide source collect runoff from hard surfaces at Bewdley
control, transforming them into ‘blue roofs’.
School, Worcestershire.

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