Further information re Request to Change Approval MCU 132003.221132.8

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            Our Ref: B09182.W.Ol.MS.ip.A uthorities.docx
            Contact: Andrew McPhail
                                                                                                                                              BROWN
                                                                                                                                                     Smart Consulting

            RPS Australia Asia Pacific
            C/ Brown Consulting (QLD)Pty Ltd
                   -




           PO Box 997
           BUDDINA QLD 4575


                                                                                                                                                             17 April 2013
           Attention: Sian Davis




           Dear Sian,


           Proposed Residential Development Lake Doonella, Noosa Stage C            -




           Stormwater Management Plan (Quantity)

           Updated Management Strategy

           Brown  Consulting (QLD) Pty Ltd have previously prepared a Flood Investigation & Stormwater
           Management Plan (Report No. B09182.W-02A dated October 2011) for Stockland Pty Ltd for the
           proposed Stage C Residential Development at Lake Doonella, Noosa.

           A  hydrological analysis was previously undertaken to determine the change in peak flows from the
           proposed Doonella Subdivision and the mitigation provided by the pl:Oposed stormwater detention
           measures. Hydraulic modelling was also undertaken to detennine
                                                                             post development flood levels to
           confirm proposed lot and road levels had appropriate flood immunity
                                                                               along the environmental corridor
           through  the site.


           Since the submission of this report, Sunshine Coast Regional Council
                                                                                                                                        (SCRC)has indicated that the use
           of the environmental corridor for detention                                           (referred              to as   the Dodonaea Close Detention Basin)
           outlined in the Stonnwater Management Plan was not acceptable.
                                                                             Subsequent meetings with SCRC
           have led to the design change process. New peak flow
                                                               management options have been proposed, with
           Option 3 deemed to be viable. This was indicated in an email from Senior Development Planner
           Dennis Wallace dated 30 March 2013 (refer to Attachment 1) in which it stated:


                   Oftbe SW7I1 options submitted, onlY Option 3 was a presented as viable and doem’, appear to provide significant
                   benefits over the originalproposal in regard to soil Irydrology and impacts ojC).."isting vegetation, On this basis, council
                   would be willi11g to amend the approval(s) to allow for the originallY proposed Dodollaea detention
                                                                                                                             area, provided we
                   can also do thefollowing:


                                 Allow forfaunapassage, includillg afauna underpass;
                                  Rebabilitate tbefau11a corridor area post construction disturbances a11d the
                                                                                                                  changes to tbe soillrydrology
                                  and vegetation that will resultfrom the detention area;

                                  Obtai11 an Op lForks revegetation/ rehabilitation approvalfor tbe above.


           This letter report presents the analysis and results for the new peak flow
                                                                                        management strategy
           (Option 3) for the proposed residential subdivision as requested by Council. It is noted that                                                             post
           construction rehabilitation of the environmental corridor is outside the
                                                                                                                                         scope of this letter,



           Level 6,199 Grey Street South Brisbane QLD 4101 Australia                                           Brown Consulting (QLD)Pty Ltd
           PO Box 10349 Adelaide Street Brisbane QLD 4000 Australi~                                            ABN 38 109 428 506
           Telephone +61 738953444                         Facsjmile +61 738953400                             brownc{)nsulting.com.nu