2014-11-17 General Committee Agenda

GENERAL COMMITTEE MEETING AGENDA   17 NOVEMBER 2014




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GENERAL COMMITTEE MEETING AGENDA                                                             17 NOVEMBER 2014

                          Date:   6 November 2014
               Your Reference:                                             cay
               Mr Dennis Pitman                                            Catchments & Creeks Pty Ltd
               51 Garnet St                                                ABN 34 078 164 119
               COOROY Qld 4563                                             P.O. Box 314
                                                                           Ferny Hills, Qld 4055
                                                                           WIH: 07 3351 3505
                                                                           Mobile: 0417 733 396
                                                                           E-mail: [email protected]
                                                                           Specialists in creek engineering, soil
                                                                           erosion, stormwater management
                           FLOOD IMPACTS OF PROPOSED GARNET STREET UPGRADE

               Executive summary
               In brief:
               e   Even though debris blockage in excess of 20% is possible at this site, it would appear to me
                   that in this case 20% blockage is an acceptable value to use for most design purposes;
                   however, | have expanded on this issue in Table 1.
                e  Inregards to potential adverse impacts on your property, the biggest concern | have with
                   the road upgrade proposal is the placement of crash barriers along the floodway. | believe
                   that in this environment it would be reasonable to expect 100% blockage of solid steel crash
                   barriers (this is a design condition that was regularly adopted in Brisbane City Council).
                Introduction
                | refer to your e-mail of 4 November 2014 concerning the potential flood impacts of the proposed
                Garnet Street upgrade and our meeting on the same day. In preparing this report | have
                reviewed the following reports:
                e  16 June 2010, letter from Sunshine Coast Council to Max Watterson & Associates
                e  4March 2013, Water Technology report to Sunshine Coast Council: ‘Garnet Street Upgrade,
                   Cooroy — Technical Review of Proposed Culvert Upgrade Works’
                e  29 July 2014, Hydrology & Water report prepared for Peet Limited: ‘Garnet Street Culvert
                   Upgrade Hydraulic Assessment’
                e  14 October 2014, Noosa Council ‘Planning & organisation Committee Meeting Agenda
                e  17 October 2014, letter from Hydrology & Water to Noose Council: ‘Proposed Garnet Street
                   Culvert Upgrade — Additional Flood Model Results’
                e  23 October 2014, letter from D.Pitman to Noosa Council
                It is noted that in conducting this review | have not performed the following tasks:
                e  checking the catchment hydrology
                e  checking the set-up and operation of any numerical models
                e  checking the development codes relating to minimum floor levels, and road and culvert
                   design, adopted by Noosa Council

                Printed: 06 November 2014       CREEKS: CORRIDORS OF OPPORTUNITY                Page ‘li

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