220508-R001(B) Engineering and Services Report (OPW) · OPW23/0179

Page 2

                                                                  1




DOCUMENT INFORMATION
 Document Title:                                                      220508-R001
 Reference Number:                                                    220508
 Commissioned By:                                                     Michael Cullen
 Prepared By:                                                         DME Projects Pty. Ltd.
 Author:                                                              Dale Martin
 Reviewed and Approved By:                                            Dale Martin (BEng, RPEQ 16845)



REVISION STATUS
  Revision                        Status                                    Reviewed By                         Date
     A                  For Information & Review                             D. Martin                       13/09/2022
     B              For Approval (Operational Works)                         D. Martin                       13/11/2023



This document must be used only for its intended purpose. Any unauthorised copying, dissemination or use in any form or by any means
is prohibited without written consent. Copyright of this document belongs to DME Projects Pty. Ltd. All Rights Reserved.

Page 3

                                                                        2


Contents
1.0     INTRODUCTION ...................................................................................................................... 3
  1.1      Background ......................................................................................................................... 3
  1.2      Scope..................................................................................................................................... 3
  1.3      Description of the Subject Site ....................................................................................... 3
      1.3.1       Location ........................................................................................................................ 3
      1.3.2       Land Use and Existing Site Conditions ............................................................... 4
      1.3.3       Topography and Stormwater Conveyance .......................................................... 4
      1.3.4       Description of Development.................................................................................... 4
2.0     ACCESS, CARPARKING & EXTERNAL WORKS ............................................................ 4
  2.1      Vehicle Access and Carparking ..................................................................................... 4
  2.2      Pedestrian Access and External Works ....................................................................... 5
3.0     EARTHWORKS ....................................................................................................................... 5
  3.1      Cut and Fill Operations..................................................................................................... 5
  3.2      Basement Excavation ....................................................................................................... 5
4.0     SERVICES ................................................................................................................................ 6
  4.1      Water Reticulation & Sewer Connection...................................................................... 6
  4.3      Communications ................................................................................................................ 6
  4.4      Waste Collection ................................................................................................................ 6
5.0     FLOOD IMMUNITY .................................................................................................................. 7
  5.1      Flood Water Protection..................................................................................................... 7
6.0     STORMWATER AND DRAINAGE ....................................................................................... 7
  6.1      Lawful Point of Discharge................................................................................................ 7
  6.2      Stormwater Drainage System ......................................................................................... 7
7.0     CONCLUSION .......................................................................................................................... 7
APPENDIX A – ENGINEERING DRAWINGS (OPW) ................................................................... 8
APPENDIX B – GEOTECHNICAL REPORT .................................................................................. 9
APPENDIX C – STRUCTURAL ENGINEERING DRAWINGS .................................................. 10
APPENDIX D – DEWATERING AND ASS PLAN FLOOD ........................................................ 11
APPENDIX E – FLOOD SEARCH CERTIFICATE (MCU) .......................................................... 12

Page 4

                                                  3


1.0 INTRODUCTION

1.1      Background
DME Projects has been engaged to prepare an Engineering Report to support an Operational Works
(Access, Frontage Works, Stormwater Drainage work, Earthworks) development application
associated with the approved Dual Occupancy on land at 128 Gympie Tce in Noosaville (refer Noosa
Council MCU22/0171) This report expands on the previous revision to provide technical supporting
information and engineering details for the proposed development including layout, provision of
necessary services, access arrangements and other relevant engineering constraints that require
consideration in the design and assessment processes. This revision also incorporates relevant
engineering design outcomes that were developed in response to various Council requests
throughout the MCU DA Phase.

1.2      Scope
The report provides details on the followings items;

        A summary of proposed external works as per Condition 27 and 28;
        Property access arrangements and car parking for the dwellings as per Condition 29 and 30;
        Site stormwater management as per Conditions 31&32;
        A summary of provision of water, sewer, power, communications and other necessary
         services to each lot;
        Earthworks and retaining (both permanent and temporary) of the proposed basement and
         Geotechnical Stability as per Conditions 39 and 40;

1.3      Description of the Subject Site
1.3.1 Location
The subject site is located at 128 Gympie Tce in Noosaville and and is described as Lot 1 on
MCH3881, within the Noosa Local Government Region. (Subject Site Details below in Fig. 1). Lot 1
has an area of 556m2 with frontage to Gympie Tce to the south and Council land (Chaplain Park)
adjoining the Noosa River to the north.
Fig. 1 Subject Site




                                              (QLD Globe)

Page 5

                                                  4


1.3.2 Land Use and Existing Site Conditions
The site lies within a Medium Density Residential Zone as per the Noosa Plan 2020. The site was
previously developed as motel style short term accommodation however these buildings have been
demolished and removed, and as such the site is currently vacant land.

1.3.3 Topography and Stormwater Conveyance
Levels across the site range from RL 2.0m AHD to 1.4m AHD, generally sloping to the south towards
Gympie Tce. Approximately 10% of the lot, at the northern most portion falls towards the Council
land adjoining the northern boundary. Stormwater runoff from the site follows the topography,
reporting to Councils kerb and channel in Gympie Tce where a network of underground pipes convey
flows to the waterway east of the site and north across Mill St to the River.

1.3.4 Description of Development
The proposed development will deliver a Dual Occupancy with the units being defined by upper and
lower storey. A basement car park will provide off street carparking and storage. Fig. 2. Below
shows an architectural image of the proposed development.
Fig. 2 Proposed Development




                                          (Sparks Architects)


2.0 ACCESS, CARPARKING & EXTERNAL WORKS

2.1     Vehicle Access and Carparking

The Operational Works development application enables vehicle access from Mill Street via the
existing access Easement B on SP305586 as per Condition 29 of MCU22/0171.
The Engineering Drawings (220508 ISSUE D – 31/10/23) can be found in Appendix A and include
detailed driveway and parking area designs to demonstrate compliance with the Condition. Five (5)
carparks are located within the basement at right angles to the access ramp. Detailed vehicle turn
paths have been prepared using Autodesk Vehicle Tracking 2023 and demonstrate that the proposed
carparking and access layouts are functional and practical given the space available. 2xB99 vehicle
parks and 3xB85 vehicle parks are demonstrated in accordance with AS2890.1 Appendix B (including

Page 6

                                                  5


clearance envelopes). Noting the requirements of Condition 30, Table 9.4.1.4 of the Planning
Scheme Parking Code only requires 3 carparks for this development, the provision of 5 compliant
carparks exceeds the minimum requirement and is considered a good outcome for future users of
the development.
A driveway longitudinal section has been provided and demonstrate the driveway grades meet the
requirements of AS2890.1 Section 2.6. Grade changes and transitions have been modelled also to
demonstrate that there is sufficient vertical clearance for vehicles to enter site and the basement. A
ground conflict report has been produced by the software to analyse the tracking of vehicles over
the design surface and shows that a B85 vehicle maintains clearance to the driveway surface at all
times. Minimum headroom as per AS2890.1 Section 5.3 is also demonstrated.
Works within the easement are as per previous drawing issues and require minimal works within the
adjoining lot, limited to extending the concrete pavement to connect the existing surface with the
subject site. The existing infrastructure in the adjoining lot does not require extensive modification
to facilitate access to the proposed development.


2.2     Pedestrian Access and External Works
The site is serviced by existing Council concrete footpaths across the Gympie Tce frontage and within
Council land adjacent to the northern boundary. The proposed works includes pedestrian access to
the existing path at the northern boundary, and construction of a new 2.0m wide concrete footpath
along the frontage of Gympie Terrace as per Condition 27 and 28. The Engineering Drawings refer to
Council Standard Drawing RS-065 for footpath construction details.



3.0 EARTHWORKS

3.1     Cut and Fill Operations
Earthworks will be required to deliver the proposed development and includes excavation for the
basement and installation of fill to achieve the design finished surface levels. The Engineering
Drawings include cross sections at key locations to demonstrate the depth of excavation and filling
as well as an earthworks map showing the extent and depth of earthworks/filling across the site.

3.2     Basement Excavation
The basement extents are shown on Engineering Drawings and require excavation below the existing
surface. The depth of excavation is less than 2.5m and will generate approximately 550m3 of spoil
to be taken off site. A Geotechnical Investigation and Report has been prepared by Pacific Geotech
and can be found in Appendix B. The report addresses the requirements of Conditions 39 and 40,
and informs the structural design. Structural Engineering drawings have been prepared by SCG
Consulting Engineers and can be found in Appendix C. These drawings detail retaining wall
structural details within the permanent works and provide a concept design for a contiguous pile
temporary retaining wall to enable the excavation of the basement. The final design and
implementation of the temporary works will be the responsibility of the construction contractor.

A detailed Groundwater and Acid Sulphate Soils Management Plan has been prepared by ADG
Consulting and can be found in Appendix D. The report addresses the requirements of Condition 32
specifically as well as other general development compliance outcomes.

Page 7

                                                  6


4.0 SERVICES

4.1      Water Reticulation & Sewer Connection
The previous development utilised a water service connection at the south western corner of the
site via a 300dia trunk main that exists adjacent to the southern boundary within the Gympie Tce
road reserve. The development will use the existing main connection location and will require the
installation of new meters in accordance with a Unitywater connection application.

An existing 150dia uPVC sewer reticulation main is located within an easement adjacent to the
northern boundary. It is expected that the proposed development will connect to the network using
the existing property connection stub directly to an existing manhole near the north west corner of
the site. Fig. 3 below shows the existing water and sewer reticulation.
Fig. 3 Existing Water and Sewer Reticulation




                                                                                      (Unitywater Mapping)
4.2      Electrical
It is expected that the proposed development will gain electrical supply from the existing overhead
network in Gympie Tce. The developer will negotiate with Energex for the installation of overhead
equipment that may include an additional property pole within the subject site.

4.3      Communications
Underground communications equipment exists within the Gympie Tce verge and is expected to
provide a suitable point of connection for the proposed lots. The developer will negotiate with
Telstra/NBN to identify connection capability and any upgrades or network extensions that may be
required.

4.4      Waste Collection
It is proposed to utilise Council’s on-street waste collection service with a bin storage for each unit
located within the basement. Residents will transport their own bins to the kerbside for collection via
Mill Street. The bin store has been integrated into the basement to ensure easy access for residents
and screening from the street.

Page 8

                                                  7


5.0 FLOOD IMMUNITY

5.1     Flood Water Protection
Flood immunity is consistent with the MCU approval and is provided by a continuous
bund/impervious walls extending to RL 2.400, being the Defined flood Event as per relevant Council
Flood Search information which can be found in Appendix E. The driveway access across the
western boundary rises to RL = 2.400m before ramping down to the basement. The extents of the
bund/walls is shown in the Engineering Drawings. Non-return devices are included on all
stormwater outlet pipes to prevent ingress of flood water during an event.



6.0 STORMWATER AND DRAINAGE

6.1     Lawful Point of Discharge
The development does not propose to significantly alter the existing site drainage arrangements.
Roof catchments and surface runoff will report to an internal network of pipes discharging to kerb
and channel in Gympie Tce. A small portion of the site will discharge to the rear as surface runoff
but this will be minimal. Both scenarios offer a lawful point of discharge. The Operational Works
outcomes are consistent with the MCU approval.

6.2     Stormwater Drainage System
The proposed stormwater drainage system is in accordance with the requirements of Condition 31
of the MCU approval and is as per the previous engineering design and information provided to
Council during the MCU approval process.



7.0 CONCLUSION

Based on all the information available it is considered that the proposed Operational Works
associated with the Dual Occupancy development at 128 Gympie Tce Noosaville can be readily
undertaken with no significant engineering constraints. The proposal achieves general compliance
with The Noosa Plan 2020 and other relevant standards and codes and is recommended for approval
accordingly.

Page 9

APPENDIX A — ENGINEERING DRAWINGS (OPW)

 

Page 10

APPENDIX B — GEOTECHNICAL REPORT

 

Page 11

10

APPENDIX C — STRUCTURAL ENGINEERING DRAWINGS

 

Page 12

11

APPENDIX D — DEWATERING AND ASS PLAN

 

Page 13

12

APPENDIX E — FLOOD SEARCH CERTIFICATE (MCU)