Page 128 - Newham SuDS DESIGN & EVALUATION GUIDE
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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



           London Borough of Newham SuDS D & E Guide                                                     © 2018 McCloy Consulting & Robert Bray Associates  London Borough of Newham SuDS D & E Guide                                                     © 2018 McCloy Consulting & Robert Bray Associates
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