Page 36 - 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.





























           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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