Page 40 - Oxford City SuDS DESIGN & EVALUATION
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Concept Design  7.4.6  Introducing sub-catchments           When integrating SuDS into a development,

           Many drainage designs adopt an approach
                                                                  the site should be divided into sub-
           where all flows are taken to the lowest point
                                                                  catchments to maximise treatment and
           of the site and attenuated in a single location,
                                                                  storage capacity.
           often referred to as a ‘pipe-to-pond’ or ‘pipe
           to box’ approach.
                                                                  The sub-catchment boundary is usually
                                                                  defined as the surface area which drains to a
           The ‘pipe to pond’ approach can result in
           unsightly, polluted and sometimes hazardous
                                                                  considered as a mini-watershed.
           pond or basin features that offer little
           amenity or wildlife benefit. The ‘pipe to box’         particular flow control, and can be
                                                                  Flows are conveyed from one sub-catchment
           approach results in below-ground structures            to the next along one or more management
           that provide no amenity or wildlife benefit at
                                                                  trains, following the modified flow routes
           all. All end of pipe solution may fill with silt       determined early in the design process.
           and generate management problems.
                                                                  Each sub-catchment contributes flows to the
                                                                  following sub-catchment or to an outfall.










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           Controlled flows are released from one sub-
           catchment feature to the next, as here at Birchen
           Coppice Primary School, Kidderminster.




























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