Page 37 - Lewisham SuDS DESIGN & EVALUATION
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7.4.3  Collection of runoff from hard surfaces

      The way that runoff is collected from roofs,           Surface collection in channels, gutters and
      roads, car parks and other hard surfaces is a          permeable pavements, or as sheet flow onto
      critical consideration in any SuDS design.             grass surfaces, keeps runoff at or near the
                                                             surface, enabling cost-effective and visually         Concept Design
      Conventional drainage techniques such as               legible design.

      gully pots and pipes, promote the
      concentration of flows and mobilisation of             Collection of runoff at or near the surface
      pollutants, forcing runoff deep underground,           also reduces maintenance costs, and allows
      so that management of runoff at or near the            for simple removal of blockages.
      surface is difficult to achieve.



                                                             Highway runoff is intercepted using a chute
                                                             gully and taken into a conveyance swale at this
                                                             retrofit SuDS project. Devonshire Hill, Haringey.














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                                                               Permeable paving and planted open channels
                                                                collect runoff from hard surfaces at Bewdley
                                                                                      School, Worcestershire.





























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