Page 128 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads

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Detailed Design 9.11 SuDS Components Source Controls providing storage Source Controls providing collection & Detailed Design
conveyance
Competent design and detailing of SuDS
Providing storage throughout the site
components ensures that runoff is collected,
(distributed storage components), means
Water must either be kept at or near the
that every opportunity for storage across the
conveyed, cleaned, stored, controlled and
surface to allow runoff to flow into SuDS
discharged from site in an effective manner.
site is exploited, greatly reducing the overall
structures, or it must be collected through
volume and size of site controls.
permeable surfaces.
The general principles of SuDS component
Source controls remove most silt, heavy
design are considered in the SuDS Manual
The simplest method of collection of runoff
2015 Sections 11-23. The purpose of this
basins, wetland and ponds to be designed as
section is to outline some of the key
as sheet flow from a hard surface. Where
considerations, experiences and practical metals and heavy oils from runoff, allowing from an impermeable surface is to intercept it
site assets.
runoff flows directly from hard surfaces to
detail solutions of commonly used SuDS filter strips or swales then runoff must leave
components garnered over many years by ■ green/ blue roofs the hard surface effectively without the risk
the authors. ■ raingardens of ponding.
Pershore High School, Worcestershire.
The following classifications are not rigid, for ■ bioretention ■ swales Low risk access road with 1.2m wide filter strip
example a permeable pavement can be source control and conveyance swale.
considered as both source control and site ■ permeable pavements ■ filter drains
control where it provides the required site
storage:
Collection and connection Site Controls

Where runoff is collected from roofs, Where runoff is collected at the surface, a
123 conveyance to the SuDS component may be depression in the ground, mimicing hollows in 124

required. Historic urban design shows us a the natural landscape, is the easiest and most
Strutts Centre, Belper.
A retrofit downpipe shoe and number of surface collection methods cost effective way to manage large volumes Pershore High School, Worcestershire.
brick channel into a raingarden. including spouts, surface channels and rills. of water in the landscape. Swale conveyance into pond site control for
final treatment and storage.
How runoff is collected and conveyed under Where landscape is limited, storage
crossing points such as footpaths and roads opportunities within pavements and on roofs
is a primary consideration of any SuDS should be explored.
design. Design details such as road gullies Careful design can maximize opportunities
can artificially increase the depth and cost of
with different design volumes in different
SuDS.
places providing maximum opportunities for
■ channels & rills multi-functional use and biodiversity.

■ filter strips ■ basins

■ pipe connections ■ wetlands

■ ponds

■ storage structures

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