Page 72 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads
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Design and Evaluation Stage 3 –
      Detailed Design  9.0                                                                                                   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
                                                                                                                                ■
                                                                                                                                 provide sufficient information to give the
                                                                                                                                                                                       opportunities for amenity and biodiversity
           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.


           Newham Council SuDS D & E Guide                                                                        © 2020 McCloy Consulting & Robert Bray Associates  Newham Council SuDS D & E Guide                                                                        © 2020 McCloy Consulting & Robert Bray Associates
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