Page 68 - Newham SuDS DESIGN & EVALUATION GUIDE
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Outline Design  8.6  Affordability                          more expensive but avoids extensive pipe                   8.8  Outline information required for SuDS evaluation                                                        Outline Design

           The design of SuDS is influenced by the type
                                                                                                                             8.8.1
           of development and how important each
                                                                  work, gullies, manhole, dedicated SuDS
                                                                                                                             The information required at Outline Design
                                                                                                                                                                                    The Outline SuDS Design will show what the
           component is to the appearance and
                                                                  storage and in some situations oil
                                                                                                                                                                                    scheme will look like, how it will function and
                                                                                                                             stage will depend on whether a Concept
           functionality of the scheme.
                                                                  interceptors. The open graded sub-base
                                                                                                                             Design has been provided and the level of
                                                                                                                                                                                    confirm any additional information provided
                                                                  provides 30% void storage which is
           An urban renewal project in the city will
                                                                                                                                                                                    since Concept Design Stage.
                                                                                                                             information included at that stage.
           require a different approach to the visual
                                                                  of maintenance into the future.
           quality than a simple SuDS design for a
                                                                                                                             plan form, confirming site layout and SuDS
           suburban layout.                                       confirmed by a flow control and a low level                The design information should be provided in
                                                                  Completing a cost comparison for permeable
                                                                                                                             infrastructure together with a SuDS Design
                                                                  pavement demonstrates the wider
           SuDS components are cost effective when                                                                           Statement presenting all information that
                                                                  considerations of drainage, surfacing and
           compared to conventional drainage but cost                                                                        cannot be conveyed on plan.
           savings are only realised through good SuDS            engineering profiles that have to be
                                                                  considered.
           design.
                                                                                                                             8.8.2  Outline Design – information checklist
           A good example of cost effective SuDS                   Evidence for the cost effectiveness of
           design is the use of permeable pavement as                                                                        Information recommended in the ASA Practical
                                                                   SuDS can be found here: http://www.
           a replacement for impermeable surfaces. The             susdrain.org/resources/evidence.html                      Guidance
           cost of the profile construction is marginally
                                                                                                                                ■  Flood Risk Assessment (FRA) – a review              ■  ground investigation review
                                                                                                                                 of critical elements
                                                                                                                                                                                       ■  evidence of third party agreement for
  63       8.7  Management of the SuDS resource                                                                                 ■  Outline Design Strategy Statement                   consent to discharge or agreement in               64
                                                                                                                                                                                       principle.
           The future maintenance of SuDS is influenced           In other locations a SuDS feature can                         ■  Outline Design Plan – layout
           by design. Wherever possible the idea of               contribute to landscape infrastructure e.g.
           ‘passive maintenance’ should be considered             the ‘rain garden’ or ‘bio retention’ element in               ■  the plan will incorporate preliminary
                                                                                                                                 landscape proposals
           with SuDS components integrated into the               design.
           everyday management.
                                                                  Wherever possible maintenance should be
                                                                                                                             Additional information to inform evaluation of the scheme:
           Although there will be situations where                allocated to site care rather than SuDS

           dedicated SuDS components are appropriate              management.
           e.g. a pond or wetland, many SuDS features                                                                           ■  topographical information and flow route            ■  sensitive receptors for runoff where
                                                                  This reduced dedicated maintenance                             analysis                                              appropriate e.g. SSSIs
           can be incorporated into multifunctional
                                                                  obligation can sometimes be reduced to just
           space e.g. courtyards, play basins and                                                                               ■  destination and discharge route of rainfall         ■  offsite works that may be required
                                                                  checking inlets, outlets and control
           recreational space.                                                                                                   via infiltration or runoff
                                                                  structures.                                                                                                          ■  general maintenance principles

                                                        Design Note :                                                           ■  infiltration investigation results where            ■  design life of any products used and
                                                                                                                                 appropriate
              Well designed SuDS are not ‘land hungry’ in that they can be integrated into both hard and                                                                               requirements for potential replacement.
              soft landspace spaces which are available within development. Making SuDS cost effective                          ■  existing utilities plan confirming existing
                      reinforces the requirement to consider SuDS layout at Concept Design stage.                                watercourses or sewer locations




           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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