Information Request OPW25 0042 [As Published] · OPW25/0042

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                        Provide a table identifying each property fronting Serenity Close for the section of
                        Serenity Close which grades to the sag and provide an explanation of how the direction
                        of drainage for each property has been determined (in particular, where it is assumed to
                        not fully drain to Serenity Close).
                 2.     Clarify what design blockage values have been adopted for the stormwater inlets in the
                        design case in the overland flow assessment.
                 3.     Clarify what climate change assumptions have bene adopted in the overland flow
                        assessment.
                        It is suggested that SPP2-4.5 and a planning horizon of 2100 be adopted consistent with
                        the current methodology of ARR.
                 4.     It is noted that 1% AEP (2100) immunity for the staff facilities building is achieved by the
                        use of a levee (block wall).
                        It would be preferable if the levee was only used to achieve freeboard rather than 1%
                        AEP (2100) immunity.
                 5.     Provide further contours or sections in the location of RIP 3B and RIP 5 to demonstrate
                        that surface levels or an overland flow path (which may be informal) will allow and
                        surcharge flows from these devices to flow to a lawful point of discharge without
                        impacting any of the development buildings or facilities.
                 6.     It is noted that a gabion rock wall is specified as the method of retaining along the edge
                        of the overland flow swale in places. Given the ability of water to seep into this type of
                        retaining (large voids), it is unclear if this method of retaining is suitable for the edge of
                        a drainage channel and if a more suitable method is available that provides better long-
                        term performance of the channel and adjoining areas.


                 Issue – Overland Flow Channel
                 The design of the Overland Flow Channel includes roughness assumptions consistent with
                 mown grass or rock at a maximum batter of 1:2. Council has concerns with the ability to
                 provide long-term stabilisation for a grass or rock 1:2 batter.
                 Information Required
                 7.     Provide additional detail demonstrating how long-term stabilisation will be provided to
                        the batters of the Overland Flow Channel. The additional detail must be prepared by a
                        suitably qualified person (RPEQ) and include treatment options consistent with the
                        current hydraulic design assumptions of the Overland Flow Channel (i.e., turf or rock).
                        Where long-term stabilisation of the proposed 1:2 turfed/rocked batter isn’t achievable,
                        provide a revised set of drawings amending the Overland Flow Channel to include a
                        reduced batter (i.e., a 1:3 vegetated batter).


                 Issue – Extent of Vegetation in Overland Flow Channel
                 The higher order development plans suggest that the trapezoidal channel will include
                 landscaping (beyond turf) in the Overland Flow Channel. This is Council’s preferred outcome.
                 However, the inclusion of vegetation within this channel is inconsistent with the current
                 hydraulic design assumptions and could lead to flow breaking out of the channel and cause
                 flooding.
                 Information Required
                 8.     Confirm the Overland Flow Channel will be vegetated to achieve a natural channel
                        design and meet the required hydraulic design assumptions.




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Document Set ID: 23692869
Version: 3, Version Date: 16/04/2025

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                 Item – Construction Traffic
                 A Traffic Impact Assessment has not been provided as part of the application material.
                 Council recognise that the haulage operations are likely to cause impacts to the local road
                 network and associated road infrastructure.
                 Information Required
                 9.     Provide a Traffic Impact Assessment (TIA) to assess the impacts of construction traffic
                        associated with the prescribed works. The TIA must be prepared by a suitably qualified
                        person (RPEQ) with Traffic Management Design qualification, in accordance with the
                        Department of Transport and Main Roads Guidelines, and must include, but not be
                        limited to:
                        a.      a Road Safety Audit;
                        b.      Pavement Impact Assessment;
                        c.      a Traffic Management Plan – the Traffic Management Plan must be developed in
                                accordance with the Queensland Manual of Uniform Traffic Control Devices
                                (MUTCD) and the Queensland Guide to Temporary Traffic Management (GTTM);
                        d.      proposed haulage route – including the scheduled duration of excavation/haulage
                                works, number of haulage vehicles exiting the site per hour, and the type of
                                haulage vehicle (i.e., truck or truck and dog); and
                        e.      the receiving location(s) of the exported spoil.
                 3.     DUE DATE FOR RESPONSE TO INFORMATION REQUEST

                 The due date for providing the requested information is 22 July 2025. Email your response to
                 [email protected]. Please advise Council of your response to this information request
                 in accordance with section 13 of the Development Assessment Rules.
                 If you do not provide a response before the due date, it will be taken as if you have decided
                 not to respond to the information request and Council will continue with the assessment of
                 your application.
                 4.     OTHER DETAILS

                 You can follow the progress of this application online at www.noosa.qld.gov.au. The “Online
                 Services” page can be accessed via "Quick Links" on the left hand side of the screen.
                 Should you have any further queries in relation to the above, please do not hesitate to contact
                 me on the number above.
                 Yours faithfully,




                 Daniel Epps
                 Senior Development Engineer




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Document Set ID: 23692869
Version: 3, Version Date: 16/04/2025