Reference Document - Storm Water Management Plan 132001.210327.1

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                 5         Flooding
                 The site is not identified as being impacted by flooding as per NSC Flood Hazard Mapping.



                 6         Lawful Point of Discharge
                 The lawful Point of Discharge (LPD) for the subject lot is the downslope eastern boundary of the site.
                 This lawful point of discharge is compliant with Section 3.9.1 requirements of QUDM.



                 7         Developed Case
                 7.1       Proposed System
                 It is proposed to reuse the existing rubble pit which had been sized for the existing dwelling and to install
                 a new second rubble pit for the new garage and new home office, refer to attached drawings in the
                 Appendix.
                 The roof area of the existing garage, guest pavilion and dilapidated roof section which are being
                 removed is of similar size to the proposed family room and new roof section (within 10m2). Therefore,
                 it is proposed to connect the roof area of the proposed family room to the existing stormwater downpipe
                 outlet and existing rubble pit.
                 The new garage and new home office are proposed to discharge to a new 2.4m long ‘Evertrench Large’
                 (or approved equivalent) stormwater disposal system. This rubble pit system has been sized in
                 accordance with the Moreton Bay Regional Council Stormwater for domestic buildings fact sheet. The
                 rubble pit has been positioned to avoid sheet flow being directed towards any buildings or structures.
                 Further, sizing was checked using additional industry adopted soak well design guidance.

                 7.2       Stormwater Quality Management
                 Stormwater quality measures do not apply for this development approval.
                 The State Planning Policy states that stormwater management design objectives do not apply for
                 premises smaller than 2500m2. This lot has an area of 1,105m2.

                 7.3       Stormwater Quantity Management
                 The minor increase of 56m2 in impervious area for this renovation does not require any stormwater
                 mitigation. The site is also located within 100m from Sunshine Beach. Detention is not required this
                 close to the ocean as it will not coincide with the peak flows in a storm event.




                 28 August 2024


Document Set ID: 23245585
Version: 1, Version Date: 16/09/2024