Referenced Document MCU13/0171

                                                               Urban Stormwater Quality Planning Guidelines 2010




Water quality   Stormwater flows from undisturbed and disturbed areas—                 As far as is reasonable and practicable, all run-off from disturbed areas is collected and
outcomes        manage to help protect environmental values                            drained to a sediment basin—up to the design storm event.
                Coarse sediment—coarse sediment is retained on site                    Achieve site discharge water quality through, for example, appropriate sediment basin
                Fine sediment—Site discharge during sediment basin dewatering          design and operation with flocculation as required.
                has a TSS concentration less than 50 mg/L
                Turbidity—Site discharge during sediment basin dewatering has a        A site-specific relationship should be developed between turbidity and suspended solids,
                turbidity (NTU) less than 10% above receiving waters turbidity—        prior to the commencement of construction on large and medium scale construction sites.
                measured immediately upstream of the site
                Nutrients (N & P)—Nitrogen and phosphorus are managed through
                sediment control.
                pH—Site discharge during sediment basin dewatering has a pH            May be further limited to prevent mobilisation of specific elements.
                range 6.5–8.5
                Litter and other waste—Prevent litter/waste entering the site, the     Avoid wind blown litter; remove gross pollutants.
                stormwater system or watercourses that discharge from the site. Also
                minimise or sufficiently contain on-site litter and waste production
                and regularly clear waste bins
                Hydrocarbons and other contaminants—Hydrocarbons and other             See the prescribed water contaminants in schedule 9 of the Environmental Protection
                contaminants are prevented from entering the stormwater system or      Regulation 2008. Waste containing contaminants must be disposed of at authorised
                internal watercourses that discharge from the site                     facilities. Store oil and fuel in accordance with Australian Standard AS1940—no visible oil
                                                                                       or grease sheen on released waters.
                Wash down water—Wash down water is prevented from entering
                the stormwater system or internal watercourses that discharge from
                the site
                Cations and anions—Cations and anions including aluminium, iron
                and sulfate are managed as required under an approved acid sulfate
                soil management plan
Stormwater      Hydraulics and hydrology—Take all reasonable and practicable           Including making best use of constructed sediment basins to attenuate the discharge rate of
drainage/flow   measures to minimise significant changes to the natural waterway       stormwater from the site.
management      hydraulics and hydrology from:
                •   peak flow for the one-year and 100-year ARI event
                    (respectively for aquatic ecosystems and flood protection)
                •   run-off frequency and volumes entering receiving waters
                •   uncontrolled release of contaminated stormwater




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