Page 73 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads

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Detailed Design 9.0 Design and Evaluation Stage 3 – 9.1 Objectives of Detailed Design ■ ■ meet the requirements for NPPF and Detailed Design

Detailed Design should develop and refine
Detailed Design
the agreed SuDS strategy from the Concept
NSTS along with Local SuDS Standards
and Outline design stages. Outputs from the
and SuDS related planning policies
detailed design should:
The SuDS strategy will be reasonably fixed by Detailed Design stage. The
confirm how the SuDS scheme maximises
■
opportunities for amenity and biodiversity
provide sufficient information to give the
management train, selection of SuDS features and general means of storing
runoff will have been evaluated and defined at earlier design stages.
the scheme will appear and operate
function passively.
The development and refinement of Concept and Outline designs at Detailed LPA and LLFA a full understanding of how ■ deliver schemes which are legible and
Design stage will demonstrate that the project objectives can be delivered
upon and will be presented with either the detailed planning application or 9.2 What Detailed Design should demonstrate

to discharge planning conditions, or reverved matters, depending upon the
The SuDS Detailed Design considers in detail ■ proportionate analysis to confirm
requirements of the LPA. all the influencing factors on the scheme with attenuation volumes with allowances for

Competent design details ensure that runoff over-arching requirements as follows: climate change and urban creep, and
is collected, conveyed, cleaned, stored, controlled flow rates for each sub-
controlled and discharged from site in an ■ the use of Source Control techniques catchment and final site discharge rates
effective manner that provides wider provides a controlled flow of clean water
benefits. through the site ■ materials and plant varieties specified
accord with local landscape character
Failure of individual elements of the design ■ demonstrate that the modified flow
can: route(s) provides for extreme flows and ■ demonstrate safe design for contractors,
67 ■ invalidate expected storage volumes and where possible connectivity corridors for operatives and general users of the site 68

flow rates biodiversity through the site
■ that SuDS which are being offered for
■ prevent adequate treatment ■ carefully consider all site levels to ensure adoption meet the relevant standards of

■ negatively impact or miss opportunities to that the system will function as intended the adopting body.
contribute to amenity use in ‘day to day’ and also extreme

■ create hazards to wildlife or miss conditions
opportunities to support biodiversity ■ demonstrate that individual SuDS
■ cause local ponding, flooding and components meet respective design

inconvenience to the public criteria
■ increase maintenance difficulty and cost.

Design Note :

Schemes invariably evolve and change from concept stage. The designer should therefore
Grey to Green project, Sheffield City Council. confirm no material changes to drainage strategy from that agreed with LPA at the Concept
Groundbreaking project integrating SuDS into
the heart of Sheffield, replacing redundant or Outline design stages. Any materials changes should be discussed and agreed with the
roadway with exciting planting, to a sequence LPA prior to detailed design submission.
of landscape cells leading to the River Don.

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