Page 78 - Hillingdon SuDS DESIGN & EVALUATION
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Detailed Design  9.3.4  Detailed Design Evaluation Checklist                                Responsibility

           The following table provides a list of key
                                                                  The CIRIA SuDS Manual Table B.3 provides
           considerations for design and evaluation.
                                                                  other aspects for checking which may be
                                                                  incorporated on a case by case basis.




                             Key design points
                                                                Key evaluation points
            Deliverable
                                                                                                  to check
            Design
                             Designers should confirm how all  Confirm allowable attenuation
                                                                rates. Confirm amenity and
                             standards have been achieved
            standards
                             for quantity, quality, amenity and  biodiversity requirements.       LPA
                             biodiversity.
            Confirm          Where positive discharge is        Review the level at which water   LLFA
            method &         made to a watercourse / sewer,     is stored relative to receiving

            locations of     consider likelihood of surcharge   flood plain levels/sewer invert.
            discharge        on storage from the receiving      Infiltration – review how
                             sewer / watercourse.
                                                                groundwater table level has been
                             Infiltration – outline how ground   confirmed and how ground will
                             will be protected from             be protected from compaction
                             compaction during construction.  during construction. Review risk
                                                                of infiltrating close to buildings.
                                                                Review how infiltration on
                                                                brownfield sites has been
  73                                                            assessed.

            Hydraulic        Detailed checklist is contained    The level of analysis required    LLFA
            calculations     Section 9.5.10.                    should reflect the risk of failure,
                                                                scale of development and
                                                                complexity of drainage.
            Detailed         Levels are crucial – check that    Sensibilty check to be performed  LLFA
            consideration    there are no locations where low  for each subcatchment,
            of site and      points might compromise design.   comparing top level of storage,
            drainage         Designer to present drawing        and lowest level of contributing
                             showing detailed levels across     areas.
            design levels
                             the site
            Drainage         Minimise risk of blockage by       Review of inlets, outlets, flow   LLFA
            details          designing protected outlets and    controls, storage, edge details,
                             flow controls                      connection details to receiving
                                                                watercourse / sewers











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