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Detailed Design  9.12 Management of the SuDS landscape

           9.12.1 The principles of SuDS

           management

                                                                  Importantly, where SuDS form part of a
           All designed landscapes require some level of
                                                                  landscape (which would be present
           management. Where maintenance is not
                                                                  regardless of SuDS), this minimal attention
           carried out development will evolve towards
                                                                  should be considered as site care and not
           woodland or an urban wasteland.

           This document introduces a ‘passive
                                                                  and pipe work is not needed which reduces
           maintenance’ approach for SuDS. This does              dedicated SuDS care. The cleaning of gullies
                                                                  overall management costs.
           not imply no maintenance but rather that
           much of the care for SuDS is site                      Passive maintenance is therefore linked to
           management rather than dedicated SuDS                  integrated SuDS design.
           maintenance.

           Hydrocarbons and other organic based
           pollution such as which wash off hard

           surfaces is broken down by natural processes
           (passive treatment), within many SuDS
           components meaning that there is no long
           term build up of organic pollution. Heavy
  139      metals and inorganic pollutants are trapped
           within Source controls at low concentrations
           and therefore form no threat to amenity
           features or aquatic environments.

           This is different to ‘intervention’ maintenance
           which is required for conventional drainage
           to remove toxic liquor from gully sumps or oil
           and grit from interceptors and separators
           which can be costly and in many cases  not
           completed, rendering the treatment function
           redundant. Intervention maintenance can also
                                                                                         Hopwood Park MSA M42.
           be required for SuDS to remove silt, however                 A light tracked excavator removes aquatic
           through the use of source controls this                    vegetation to de-water next to the wetland,
           requirement will be minimised.                                          before moving to a wildlife pile.











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