Page 33 - 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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