Appendix 3 - Stormwater quality management plan

Operational Management and Maintenance Manual for Stormwater Quality Improvement Devices                                                                     CC-3668



                                                                                                                 Maintenance         Preventative / Corrective
     Aspect            Performance Indicator           Inspection Frequency          Inspection Activities
                                                                                                                  Frequency           Maintenance Activities
 Batter Slopes and Base Invert (cont.)
 Unusual Odours, None detected.                                                    Check for any unusual                           Remove and replace vegetation
 Colours        or                                                                 odours,     colours or                          and filter media affected by
 Substances (e.g.                                                                  substances.                                     grease, oil, fuels or other
 oil and grease)                                      Immediately following                                                        substances, as required.
 Litter and Debris Maximum 1 piece per 4m2.           first 3 storm events after   Check for debris and litter                     Remove both organic and
                                                      construction complete.       (including organic litter)    As inspection     anthropogenic litter and debris
                                                      Then 2 monthly during        within the bioretention       results dictate   to ensure flow paths and
                                                      wet season / 4 monthly       system.                                         infiltration are not hindered.
 Algal or     Moss   Maximum 10% of surface           during dry season            Identify any algal or moss                      Resolve why the filter media is
 Growth              covered in algae and no moss                                  growth.                                         constantly wet, allow the
                     growth.                                                                                                       bioretention system to dry out
                                                                                                                                   and remove algae by hand.
 Outlet
 Erosion             Outlet is structurally sound                                  Identify any scouring of                        Repair damage to the outlet
                     and there is no evidence of                                   the outlet from high                            resulting from scour and if
                     erosion or subsidence /                                       velocity flows.                                 necessary      install      scour
                     settlement, including around                                                                                  protection or energy dissipation.
                     edges of rock protection or
                     tow of weir for large
                     systems.
 Damaged       or    No damage that poses a risk                                   Check the outlet structure                      Repair and/or replace damaged
 removed             to public safety or structural   Immediately following        for any damage or loss of                       or lost infrastructure.
 structures          integrity.                       first 3 storm events after   infrastructure.
 Sediment, litter    No blockage.                     construction complete.       Check for accumulated         As inspection     Remove accumulated sediment,
 or debris                                            Then 2 monthly during        sediment, debris and          results dictate   debris    and      organic and
                                                      wet season / 3 monthly       litter (including organic                       anthropogenic litter to ensure
                                                      during dry season            litter) within the outlet                       the functioning of the outlet
                                                                                   structure.                                      structure is not impeded.
 Downstream          No              downstream                                    Check         for      any                      Remove sediment where it is
 outfall             impediments to the release                                    impediments       to   the                      impeding the conveyance of the
                     of water, no erosion or                                       release of water from the                       outfall. Repair damage to the
                     damage to the outfall                                         bioretention system (e.g.                       outfall profile resulting from
                     structure, and no evidence                                    erosion,     damage     to                      scour or rill erosion and if
                     of     malfunction    (e.g.                                   structure,        sediment                      necessary re-profile.
                                                                                   accumulation, etc).



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