Page 57 - Newham SuDS DESIGN & EVALUATION GUIDE
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Concept Design  7.5.3  Preliminary water quality considerations  7.5.4  Preliminary amenity considerations        Concept Design

      Amenity relates both to the usefulness and
 At the Concept Design stage it is necessary
      the appearance of SuDS features. Ideally
 to show how water quality is managed:
      SuDS features should be integrated into the
      landscape, to minimise dedicated land take
      and management obligations.
   ■
 The design will also consider:
 A simple assessment of risk using the
      Key amenity elements to consider when
 ‘treatment stage’ approach is acceptable
 on low and medium risk development. If
 groundwater.
         ■
          Legibility – can the design be understood
 the risk screening (SuDS Manual p571)    ■  Sensitivity of the receiving watercourse or   designing SuDS features include:    ■  Multi-functionality – all parts of the SuDS
 demonstrates that  the ‘simple index     ■  Environmental and technical constraints   by users and managers?  landscape should be available for use by
 approach’ is appropriate, then the   such as contamination, protected     ■  Accessibility – can all parts of the SuDS   people when not performing a SuDS
 ‘treatment stage’ is acceptable.  landscapes, SSSI, SAC, AONB, Ancient   function.
          scheme be easily reached, both for
 Woodland and existing biodiversity
   ■  All sites should demonstrate source   recreation and maintenance? All parts of     ■  Visual character – all elements of the
 control to remove silt, heavy metals and   features.  the scheme must be safe by design. It is   SuDS design must be attractive (or at
 hydrocarbon pollution at the beginning of     ■  The LPA and LLFA will not accept the   not usually appropriate to fence SuDS   least visually neutral, e.g. inlets, outlets
 the management train.  gully pot as a method of treatment. Table   features for safety reasons (except   and control structures) and safe.
 26.15 of the CIRIA SuDS Manual denotes   toddler fences where young children may
   ■  Unless permeable pavement is used to
 that conventional gully and pipe drainage   not be fully supervised).
 collect runoff, where the pavement   provide zero treatment.
 provides high water quality treatment,
 51   there will usually be a second feature to                                                                    52
 manage additional volumes and provide
 additional treatment.   7.5.5  Preliminary biodiversity considerations
      There are key biodiversity requirements that
      should be demonstrated at the Concept
      Design stage:

 Design Note:    ■  Clean water – ‘a controlled flow of clean     ■  Topographical diversity – variation in

  Where there is a high risk of pollution, a formal risk assessment is required.  water’ is provided by the use of source   vertical and horizontal structure allows for
          control at the beginning of the                       complex habitat development. This is
 High-risk development:
          management train. Subsequent surface                  implicit in SuDS design, e.g. swales, basins,
 Trunk roads and highways – follow the guidance and risk assessment process set out in HA   conveyance and open SuDS features will
 (2009)                                                         ponds and wetlands.
          ensure connectivity and habitat
 Haulage yards, lorry parks, highly frequented lorry approaches to industrial estates and waste   opportunities.     ■  Ecological design - the creation of
 sites, sites where chemicals and fuels (other than domestic fuel oil) are to be delivered,   habitats within the development.
 handled, stored, used or manufactured and industrial sites. Discharges may require an     ■  Connectivity - habitat connections     ■  Sympathetic management – through
 environmental licence or permit obtain pre-permitting advice from the environmental   outside and within the development   considered management, a mosaic of
 regulator. Risk assessment is likely to be required.  ensure that plants and animals can travel   habitat types can be created, ensuring

 CIRIA The SuDS Manual 2015  between habitat areas.             maximum ecological value.



 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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