Page 117 - Oxfordshire SuDS DESIGN & EVALUATION
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9.9.3 Key design criteria for biodiversity in the developed landscape

      9.9.3.1 Clean water


      Clean water is critical as soon as possible for        Connectivity is inherent in the management
      all open water features in the landscape.              train principle but must be considered                Detailed Design
      Clean water is delivered using initial pollution       carefully where one feature links to the next.
      prevention measures to prevent                         Surface conveyance and overflow routes,
      contaminants reaching water, source control            with a minimum use of pipework and
      features and further site controls along the           inspection chambers, is helpful in retaining
      management train.                                      wildlife links.

                                                             There should be a direct connection between
                                                             the SuDS landscape and the blue/green
      9.9.3.2 Structural diversity
                                                             infrastructure that receives the ‘controlled
      Structural diversity both horizontally and             flow of clean water’ from the development.
      vertically within water features, the landscape
      and in vegetation generally provides habitat
      variety for wildlife. Structural diversity is          9.9.3.4 Prevent pollution to habitat
      inherent in many SuDS features particularly
                                                             Permanent vegetation should cover all soil
      swales, basins, wetlands and ponds that can
                                                             surfaces to prevent silt runoff and planting
      easily be enhanced for habitat creation.
                                                             should be designed to avoid the use of
      Ornamental planting should mimic natural               fertilizer, pesticides and herbicides.
      vegetation by developing a complex vertical                                                                  112
      structure of trees, shrubs and herbaceous

      cover.                                                 9.9.3.5 Maintenance for wildlife

                                                             Sympathetic maintenance enhances
                                                             biodiversity but should be compatible with
      9.9.3.3 Connectivity
                                                             the aspirations of the local community to
      Connectivity between wetland habitat areas             ensure acceptance of a more natural
      both within and outside the site encourages            landscape character.
      colonisation into and throughout the
      development landscape. These connections
      are particularly important both for animals on
      the ground but animals like bats use
      individual trees and woodland edges to travel

      from one place to the next and use SuDS
      wetlands to feed.







      Oxfordshire County Council SuDS D & E Guide                                                       © 2018 McCloy Consulting & Robert Bray Associates
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