Delegated Report - Code - Planning OPW25 0057 · OPW25/0057

               47.    Subsoil drains are to be cleaned out and accumulated sediment manually removed from the
                      surface of basin and coarse sediment forebays at Off Maintenance and as required during
                      the maintenance period.
               48.    All stormwater quality treatment devices must be maintained by the development in
                      accordance with Water by Design (2009) Maintaining Vegetated Stormwater Assets (Version
                      1) until they are accepted as Off Maintenance by Council.
               49.    Any defects in WSUD devices identified during the maintenance period must be reviewed
                      and a report recommending required rectification works submitted to Council and endorsed
                      by Council’s delegate. Works to repair the device and prevent the problem occurring in the
                      future must be completed and the device maintained for a minimum period of 12 months prior
                      to the WSUD device being accepted as Off Maintenance.
               50.    Prior to council accepting the bioretention devices Off Maintenance, maintenance checklists
                      including the full cost of maintaining the devices in accordance with Water by Design (2009)
                      Maintaining Vegetated Stormwater Assets (Version 1) must be submitted to Council.
                      Erosion and Sediment Control
               51.    Prescribed Water Contaminants (as defined in Schedule 10 of Environmental Protection
                      Regulation 2019) must not be released from the site or to waters within the site, or be likely
                      to be released should rainfall occur, unless all reasonable and practicable measures are
                      taken to prevent or minimise the release and concentration of contamination. These
                      measures must be designed, implemented and maintained in accordance with “Best Practice
                      Erosion and Sediment Control” published by the International Erosion Control Association
                      (Australasian Chapter) (IECA, 2008), to the extent that such measures and practices are also
                      consistent with the following:
                      a.      Minimise Erosion:
                              i.       For areas of the site which drain to a sediment basin, implement drainage and
                                       erosion control measures prior to rainfall which prevent or minimise rill erosion
                                       and gully erosion
                              ii.      For areas of the site which do not drain to a sediment basin, implement drainage
                                       and erosion control measures prior to rainfall (including contingency measures)
                                       which prevent or minimise erosion, including rain drop erosion, chemical erosion,
                                       rill erosion and gully erosion
                              iii.     Prior to the sealing of the plan of survey for the development, all site surfaces
                                       must be effectively stabilised using methods which have achieved effective short-
                                       term stabilisation and which will continue to achieve effective stabilisation in the
                                       medium to long-term. For the purpose of this condition, an effectively stabilised
                                       surface is defined as one that does not, or is not likely to result in visible evidence
                                       of soil loss caused by sheet, rill or gully erosion or lead to sedimentation, or lead
                                       to water contamination.
                      b.      Manage concentrated stormwater flows
                              iv.      Prior to each rainfall event ensure concentrated stormwater flow paths are
                                       provided with capacity in accordance with IECA (2008) Table 4.3.1 and are
                                       structurally stable in all rainfall events for the following sources:
                                       a)    From stormwater catchments upslope of the area of disturbance which are
                                             either stable or external to the site, ensure stormwater is diverted or
                                             managed either:
                                             i.    around the site or through the site without causing erosion and
                                                   without contaminating the flow; or
                                             ii    if it is impractical to convey the flows around or through the site,
                                                   convey the flows into appropriately sized sediment basins without
                                                   causing erosion.

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Document Set ID: 23977399
Version: 6, Version Date: 22/08/2025