Page 32 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads
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Concept Design  7.3  What Concept Design demonstrates                                                                  7.4  Concept Design process                            A topographical survey, expressed both as             Concept Design

                                                                                                                             7.4.1  Flow route analysis
           The SuDS Concept Design will demonstrate
                                                                  Evaluation will begin with:
           an understanding of how proposed
                                                                     ■
                                                                                                                             The natural hydrology, and the way that a
                                                                     existing flow route analysis for the existing
           development will impact on:
                                                                                                                                                                                    spot levels and contours, provides the basic
                                                                                                                             development affects how rainfall behaves on
                                                                     site
              ■
                                                                                                                             a site, are assessed initially by flow route
                                                                                                                                                                                    template for existing and future flows.
               the site and its natural hydrology
                                                                     ■
                                                                     a modified flow route analysis for the
                                                                                                                             analysis.
                                                                                                                                                                                    Geology indicates whether rainfall will flow
              ■
               historical drainage elements where these
                                                                     proposed development.
                                                                                                                                                                                    from the site as runoff, infiltrate into the
               are present
                                                                                                                             consider how a site behaves naturally before
              ■
                                                                                                                                                                                    these two ways.
               the ecology of the site and its
                                                                     ■
                                                                                                                             development. This analysis can be applied to
                                                                     Runoff collection – how rainfall is
               surroundings                                       Preliminary design will include:                           The first step in flow route analysis is to            ground, or leave a site in a combination of
                                                                     collected and conveyed to source control                re-development and retrofit sites, and is              Designers should be mindful that a site that
              ■  the landscape character of the locality             features.                                               informed largely by topography and geology.            infiltrates naturally may not continue to
                                                                                                                             There may be a number of other factors                 infiltrate once it has been developed.
              ■  natural flow routes.                                ■  Source control – runoff managed as close
                                                                                                                             influencing the analysis, including:
                                                                     as possible to where rain falls.
                                                                     ■  The management train – SuDS                              ■  historical drainage e.g. sewers or land
                                                                     components and storage features linked                      drains
                                                                     in series, which convey flows along                         ■  discharge locations
                                                                     modified flow routes through the
                                                                     development.                                                ■  contamination issues
                                                                     ■  Sub-catchments – small discrete areas                    ■  existing landscape features
  27                                                                 that manage their own runoff.                               ■  habitat considerations.                                                                               28
                                                                     ■  Maintenance – effective performance and                                                                    The final treatment stage at Hopwood Motorway
                                                                     reasonable care costs.                                                                                           Service Station. Monitoring has demonstrated
           Australia Road, London, where permeable paving                                                                                                                            that water of a very high quality (near drinking
           provides source control prior to SuDS Basins.                                                                                                                                                water standards) leaves site.





























           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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