Page 140 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads
P. 140

Detailed Design  The safety considerations in basin, wetland   3.  Permanent pond depth need not exceed                4.  All hard engineered structures should be           7.  Where unsupervised toddlers may be                Detailed Design
                                                                                                                                                                                       expected a 600-700mm picket fence
                                                                                                                                 set back 1m from permanent water edge,
                                                                     600mm as this is a common depth of
           and pond design should be considered
                                                                                                                                 which will prevent drowning in the event
                                                                     natural ponds and where most biological
                                                                                                                                                                                       should be considered as this stops most
           carefully.
                                                                                                                                                                                       toddlers and allows adults to easily step
                                                                                                                                 of concussion.
                                                                     activity occurs. However, a depth 600mm
           1.  The profile of the structure should allow
                                                                     without regular maintenance means that
                                                                                                                                                                                       over the fence for rescue.
                                                                                                                             5.  Protective fencing will not keep children
               easy and safe access for people and
                                                                     vegetation will cover the pond in time.
                                                                                                                                 out of ponds and merely acknowledges a
               maintenance machinery. Slopes should
                                                                                                                                                                                    8.  There must be an acceptance by the
                                                                     Most wetland edge plants cannot colonise
                                                                                                                                                                                       community that open water is part of a
               not exceed 1 in 3 or 1 in 4 and in larger
                                                                                                                                 dangerous condition. Well designed
                                                                     beyond 1.2m depth of permanent water.
               basins access ramps with a more gentle
                                                                                                                                                                                       sensitively communicate health and safety
                                                                                                                                 accessible for rescue if this is required.
               slope should be considered. The idea of a
                                                                     the pond, with surrounding shallower
               series of slopes and level benches is now             Therefore, an deeper area in the centre of                  ponds should be easy to exit and                      landscape character. It is useful to
                                                                                                                                                                                       messages identifying the presence of
                                                                     benches can be considered if open water                 6.  Pond depths and profiles should not be
               accepted as an appropriate detailing for                                                                                                                                permanent and temporary water using
                                                                     is desired. Effective storage of 600mm                      designed for ease of open water
               SuDS basins and ponds.                                                                                                                                                  well designed informative signage.
                                                                     over permanent water depth of 1.2m                          swimming. This can be achieved by
           2.  The overall depth of temporary storage                provides a total potential stored depth of                  varying the profile of the pond                    9.  The use of ‘danger – deep water’ signs
               should not normally exceed 600mm as                   1.8m and the design must take this into                     throughout.                                           and lifebuoys should be avoided, as they
               this depth is critical for a feeling of safety        account.                                                                                                          imply that risks have not been sufficiently
               in water. The bottom of the temporary                                                                                                                                   catered for by design.
               storage dry basin should slope gently so
               that most of the time the base is firm and                                                                    This project failed to adequately consider
               dry. Shallow micropools and wetland                                                                           health and safety when designing attenuation
                                                                                                                             features into a residential pocket park.  There is
               habitat should be integrated carefully into
                                                                                                                             now no public access allowed.  There should be
               the basin as they will not be visible when                                                                    no need for such measures if properly
  135          the basin is full of water.                                                                                   designed.                                                                                                    136


















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           Newham Council SuDS D & E Guide                                                                        © 2020 McCloy Consulting & Robert Bray Associates  Newham Council SuDS D & E Guide                                                                        © 2020 McCloy Consulting & Robert Bray Associates
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