ATTCH 3 - IR Response - Erosion, Coastal Processes and Stormwater (Dr Trevor Johnson)

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753345 2
14 November 2017

In respect of Burgess Creek, a review of available historical photographs (see attached) shows that the
mouth of the creek has not altered position significantly over the period of assessment. While there
have been changes in discharge location on the beach itself, the alignment of the creek adjacent to the
subject property has not altered. There has been no effect on the subject site as a consequence of
these beach changes, primarily because the site is significantly separated in the vertical dimension from
the creek. It is considered that development on this site will have no effect on the physical processes
which affect the location of the mouth of the creek. Similarly, on the basis of historical data, there is no
likelihood that the creek will have an erosive impact on the property.

In relation to the fore dune system, it is proposed that the site should be separated from the coastal
dune system by appropriate fencing. Access to the beach from the site is expected to be restricted to
the existing path which runs north from the site across Burgess Creek. However, it is also recognised
that the dunes are in public land accessible to all from the beach, and that there is currently no legal
restriction on persons accessing the dune area.

In relation to item 9, MUSIC modelling was undertaken in respect of the proposed development of the
site. This modelling demonstrated that an area of infiltration of 100 m? on each house lot would be
effective in controlling stormwater runoff from the site. A brief report outlining the modelling is
contained in the attached Stormwater Management Plan, and the MUSIC model itself can be provided
to Council for assessment purposes.

A similar exercise was undertaken in respect of stormwater runoff quantity. Under existing conditions, it
is unlikely that any runoff is generated from the site, because the soil is clean beach sand with high
permeability. It was calculated that the provision of a small infiltration basin with an area of about 200
m? on each house lot would be sufficient to handle all runoff up to the 1% Annual Exceedance
Probability (AEP) design storm event. This sizing is based on a long-term permeability of only 1m per
hour. In comparison, the permeability of clean beach sand would be expected to be in excess of about
8 m per hour. Consequently, the sizing is considered to be highly conservative.

The basins will contain only beach sand and be vegetated with sparse dune grass for stability
purposes. The basins will be located along the eastern boundary of each lot, such that any overtopping
for extreme events will occur as shallow sheet flow into the beach dunes.

It is proposed that the bio-retention system and the detention basin be incorporated in the same
physical basin. Consequently, an allowance of 100 m? for stormwater management on each proposed
lot is sufficient to ensure compliance with the requirements of the SPP and Council’s planning scheme.

Item 10 deals with the stormwater disposal strategy for the site. This is outlined in the attached
Stormwater Management Plan. Effectively, all runoff from the site will be captured and redirected to
bio-retention and detention basins along the eastern boundary of each lot. No stormwater will be
discharged from the site for all storms with AEPs in excess of 1%.

In relation to item 11, stability analysis indicates that the disposal of stormwater in the manner proposed

will have no adverse impact on slope stability. No stormwater outlets are proposed into Burgess Creek,
and all runoff will be disposed of by infiltration.

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753345 3
14 November 2017

It is understood that Council officers have also raised concerns in respect of the stability of David Low
Way following the completion of earthworks and house construction on the subject site. This issue has
been considered in the context of the geology of the site, and also the fact that a vegetated buffer will
be maintained between the road and the developed part of the site. There will be no impact on the
stability of any existing road components as a consequence of the development of the site.

Yours sincerely

7ef—

Dr Trevor Johnson
Engineering Consultant

Encl: Historical Aerial Photographs
Stormwater Management Plan

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753345
14 November 2017

APPENDIX A

Historical Aerial Photographs

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PRINT DATE: 24 Mare, 2017-437pm BY: JAMES WEIDMAN

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terms of the retainer. Cardno Limited does not and shall not
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‘third party arising out of any use or refance by third party .
Beach Erosion Assessment

Cardo (Ole) Pty Ltd | ABN S7 051 074 992 con the content ofthis document.
‘Aerial imagery Copyright Nearmap Ply Lid, 2016.

Kenlynn Ply Ltd

Page 6

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PRINTDATE: 26a), 2017-43pn BY: JAMES WEIDMAN

© Carcno Limited All Rights Reserved.
This documents produced by Cardno Limited soley forthe
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Castaways Beach

Beach Erosion Assessment
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terms ofthe retainer. Cardno Limited does not and shall nat
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2004 Aerial Image
Castaways Beach

Beach Erosion Assessment
Kenlynn Ply Ltd

Page 15

  
     

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Date Size
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‘on the content ofthis document
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Date Size
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2012 Aerial Image

Castaways Beach
Beach Erosion Assessment
Kenlynn Ply Ltd

Page 17

 

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Page 18

 

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Date Size
24/03/2017 A3
WE17035 1

Project Reference Revision

  
   

Scale
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Figure 14

2017 Aerial Image
Castaways Beach

Beach Erosion Assessment
Kenlynn Pty Ltd

    

Cardo (Qld) Pty Lid] ABN57 O51 074 992 onthe t
‘Aetial Imagery Copyright Nearmap Pty Ltd, 2016

Page 19

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Figure 15

Historical Dune Alignments
Castaways Beach

Beach Erosion Assessment

Kenlynn Pty Ltd

 

Cardno (Qk) Pty Lt | ABN 57 051 074 982

‘Aerial imagery Copyright Nearmap Ply Lid, 2016.

 

Page 20

753345
14 November 2017

APPENDIX B

Stormwater Management Plan

CAUsers\tejohnson\Documents\cardno\castaways info request. docx

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global environmental solutions

Castaways Beach

Stormwater Management Plan

Report Number 620.12166-R01
3 November 2017

Kenlynn Pty Ltd
c\- Peter Macgregor
63 Longman Terrace

Chelmer QLD 4068

Version: v0.1

Page 22

Kenlynn Pty Ltd
Castaways Beach
Stormwater Management Plan

Report Number 620.12166-R01
3 November 2017
Version v0.1

Page 2

 

Castaways Beach

Stormwater Management Plan

PREPARED BY:

SLR Consulting Australia Pty Ltd
ABN 29 001 584 612

Level 2, 15 Astor Terrace

Spring Hill QLD 4000 Australia

(PO Box 26 Spring Hill QLD 4004)
+61 7 3858 4800 +61 7 3858 4801

[email protected] www.sirconsulting.com

‘This report has been prepared by. SLR Consulting Australia Pty Ltd
with all reasonable skill, care and diligence, and taking account of the
timescale.and resources allocated to it by agreement with the Client.

Information reported herein is based on the interpretation of data collected,
which has been accepted in good faith as being accurate and valid.

This report is for the exclusive use of Kenlynn Pty Ltd,
No warranties or guarantees are expressed or should be inferred by any third parties.
This report may not be relied upon by other parties without written consent from SLR.

. SLR disclaims any responsibility to the Client and others
in respect of any. matters outside the agreed scope of the work.

DOCUMENT CONTROL

 

Reference Date Prepared

Checked Authorised

 

620.12166-RO1-v0.1 3 November 2017 Michael Della

T. Johnson T, Johnson

 

 

 

SLR Consulting Australia Pty Ltd

Page 23

Kenlynn Pty Lid
Castaways Beach

Report Number 620.12166-R01
3 November 2017

 

Stormwater Management Plan Version v0.1
Page 3

Table of Contents

4 INTRODUCTION 4

2 HYDROLOGIC ANALYSIS 6
2.1. Overview 6
2.2 Development Layout 6
2.3 Rational Method 7
2.4 WBNM Model 7
2.5 Summary 8

3 WATER QUALITY ANALYSIS 9
3.1 Overview 9
3.2. MUSIC Model

4 CONCLUSION 11

TABLES

Table 1 Allotment Areas 6

Table 2 MUSIC Madel Results 10

APPENDICES

Appendix A Subdivision Proposal Plan

SLR Consulting Australia Pty Lid

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Kenlynn Pty Ltd Report Number 620.12166-RO1

 

Castaways Beach 3 November 2017
Stormwater Management Plan Version v0.1

Page 4
1 INTRODUCTION

It is proposed to construct a residential subdivision at the subject site located at 2 David Low Way,
Castaways Beach, described as Lot 71 MCH 2854 (refer Locality Plan below). The proposed layout of
the site is shown in Appendix A.

159%
CPT REET

 

Image 1. Locality Plan

Noosa Council issued an Information Request dated 7 September 2017, including the following item:

Issue — Water Quality of Burgess Creek and Stability at Stormwater Outlet points

The proposed subdivision has the potential to increase hardstand area which changes frequent
flows, peak runoff velocities and water quality. The State Planning Policy (SPP) requires
developments of this nature to demonstrate that they provide mitigation measures in stormwater

SLR Consulting Australia Pty Ltd

 

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Kenlynn Pty Ltd Report Number 620.12166-R01

Castaways Beach 3 November 2017
Stormwater Management Plan Version v0.1
Page 5

 

runoff to manage frequent flows to not change to 1% AEP (sic) and achieve pollution reduction
targets of 80% reduction of Total Suspended Solids, 60% reduction of Total Phosphorous and
45% reduction of Total Nitrogen compared to a non-mitigated scenario. Additionally, Specific
Outcomes O01, O9 and O10 of the Water Sensitive Design Code of the Noosa Plan requires
developments to not adversely affect water quality, water flows or ecological values of the
receiving environment. For this development, further information is needed to confirm the
receiving environment will not be adversely impacted. The concerns with flow management are
to do with scour at the stormwater outlets, impact of scour on slope stability. Concerns with
changes to water quality have to do with potential for nutrient increases to Burgess Creek,
especially when it is closed as well as impacts of locally increased nutrients to dunal vegetation.

The application is unclear whether runoff from the development will discharge via groundwater
or overland flow to Burgess Creek or elsewhere. The size and location of any required
stormwater management devices that will result from the proposed subdivision and the impacts
it could have on site stability, asset management etc. may potentially affect lot layout/
easements etc.

Information Required

9. Demonstrate that the proposed development will meet the environmental objectives for
water quality management as required by the SPP and The Noosa Plan.

10. Provide a preliminary stormwater strategy which identifies the proposed stormwater outlet
locations and flow paths as a result of the proposed development.

11. Provide advice from a suitably experienced and qualified geotechnical engineer to
confirm that the proposed stormwater discharge strategy will not affect stability on
landslip areas or cause erosion.

This Stormwater Management Plan addresses Items 9 to 11 from the above Information Request.

SLR Consulting Australia Pty Ltd

 

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Kentynn Pty Ltd Report Number 620.12166-R01

 

Castaways Beach 3 November 2017

Stormwater Management Plan Version v0.1
Page 6

2 HYDROLOGIC ANALYSIS

2.1 Overview

As shown by the topographic data contained in the AJS Surveys Plan in Appendix A, the existing site
generally drains in a westerly direction towards David Low Way, then in a northerly direction along a
gully (on the eastern side of David Low Way), before discharging into Burgess Creek to the north of
the site.

The proposed layout consists of 6 residential allotments (as shown in Appendix A). It is proposed that
each lot is regraded in one of the following ways:

° Scenario 1 — high point at David Low Way, and lot falls to its eastern boundary, or

¢ Scenario 2 — high point near the middle of the lot, and the lot falls both to its eastern and
western boundaries.

A basin (or basins) will be constructed in each lot to intercept the runoff from that lot, ie. at its eastern
boundary for Scenario 1, or at both the eastern and western boundaries for Scenario 2. The total area
of the basin(s) in each lot will comprise the following characteristics:

e Area = 100 m?
« Detention Depth = 300 mm

Each basin will be vegetated, and will act as both a bioretention and detention basin. Further details
on the bioretention basin analysis are contained in Section 3.

The basins are sized so that they can capture and infiltrate the entire volume of runoff from each lot for
all flood events up to the 1% Annual Exceedance Probability (AEP) event, ie. there will be no
overland flow discharged from the site for events less than or equal to the 1% AEP event.

Thus, there will be no discharge of stormwater runoff or associated pollutants to Burgess Creek
following the development.

2.2 Development Layout
The area of each allotment within the development (refer Appendix A) is summarised in Table 1.

Table 1 Allotment Areas

 

 

 

 

 

 

 

 

Lot No. Lot Area Covenant Area Developable Area Building Envelope

(m?) (m*) (m*) (m*)

711 3336 2142 1194 829
712 1219 170 1049 665
713 4211 173 1038 653
714 1143 176 967 567
715 946 209 737 388
716 1819 773 1046 349
Average 1005 575

 

SLR Consulting Australia Pty Ltd

 

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Kenlynn Pty Ltd Report Number 620.12166-R01

Castaways Beach 3 November 2017
Stormwater Management Plan Version v0.1
Page 7

 

As shown in Table 1, the average developable area available within each lot is approximately
1005 m2, with an average building envelope of approximately 575 m?.

Consequently, for the stormwater analysis of the subject site, an average lot size of 1,000 m? was
adopted, with a fraction impervious of 60% (i.e. building envelope of 600 m’).

A single basin has been modelled for each lot. If the lot is graded such that it falls to the east and the

west, the total basin size (100 m?) can be split proportionally according to the size of the two
catchments.

2.3 Rational Method

The peak discharge from one of the proposed new residential allotments was estimated using the
Rational Method.

A time of concentration of 5 minutes was adopted for a developed lot, in accordance with the
Queensland Urban Drainage Manual (QUDM, 2017) recommended roof drainage system travel times.

The 1% Annual Exceedance Probability (AEP) rainfall intensity for Castaways Beach for a duration of
5 minutes is 319 mm/h.

The 10% AEP runoff coefficient (C10) for a residential allotment assuming 60% fraction impervious is
0.82.

The peak 1% AEP discharge from an average allotment using the Rational Method was therefore
calculated to be 0.087 m/s.

2.4 WBNM Model
A WBNM hydrologic model of a typical allotment was established. The design rainfall data for the
catchment was determined in accordance with Australian Rainfall & Runoff. The information used is
as follows (Source: Intensity-Frequency-Duration application on the Bureau of Meteorology website):

2 Year ARI, 1 hour Intensity 51.5 mm/h

2 Year ARI, 12 hour Intensity 10.4 mm/h

2 Year ARI, 72 hour Intensity 3.65 mm/h

50 Year ARI, 1 hour Intensity 94.2 mm/h

50 Year ARI, 12 hour Intensity 22.1 mm/h

50 Year ARI, 72 hour Intensity 8.71 mm/h

Regional Skewness 0.10
Geographical Factor F2 4.40
Geographical Factor F50 17.58

SLR Consulting Australia Pty Ltd

 

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Kenlynn Pty Ltd Report Number 620.12166-R01

Castaways Beach 3 November 2017
Stormwater Management Plan Version v0.1
Page 8

 

The design rainfall losses adopted for the analysis were:
Pervious Area: Initial Loss = 0 mm
Continuing Loss = 2.5 mm/h
Impervious Area: Initial Loss = 0 mm
Continuing Loss = 0 mm/h

A Lag Parameter of 1.30 was used in the WBNM model. Studies carried out using WBNM have found
that the average value of the Lag Parameter across a wide range of catchments is between 1.30 and
1.80 (ref. WBNM User Manual). Thus, the adopted value of 1.30 is within the accepted bounds.

The WBNM model was run for a range of storm durations, from 10 minutes to 72 hours, with the 15
minute event producing the peak discharge of 0.082 m%/s for the 1% AEP event. This value is
consistent with the flow estimate calculated using the Rational Method (as discussed in Section 2.3).
Consequently, it was considered that the WBNM model could be used to calculate the discharge
hydrographs from a developed allotment.

As discussed in Section 2.1, it is proposed to construct a basin or basins with a total area of 100 m?
within each developed allotment, to receive the stormwater runoff from that lot. If only one basin is
constructed along the eastern boundary, it would be approximately 16.7 metres long (across the lot)
and 6 metres wide. For two basins, appropriate basin sizes can be determined based on the
catchment areas draining to each basin.

The captured stormwater runoff will infiltrate into the existing sand within the basin(s). An infiltration
rate of 1,000 mm/h was adopted for clean beach sand. There is no topsoil present on the site, and no
plan to import any for the proposed development.

The WBNM model, with the inclusion of the detention/infiltration basin, was again run for a range of
storm durations, from 10 minutes to 72 hours. The peak depth in the basin for the 1% AEP event was
achieved with the 60 minute event, producing a maximum depth of 299 mm.

As discussed in Section 2.1, each basin will comprise a detention depth of 300 mm. Consequently,

there would be no overtopping of the basin for all flood events up to and including the 1% AEP flood
event.

2.5 Summary

As discussed above, the proposed stormwater strategy is to grade each allotment to a detention basin
or basins located at the downstream boundary(s) of that lot. The basin(s) will capture and infiltrate the
stormwater runoff from its respective lot for all floods up to and including the 1% AEP event.

Consequently, there is proposed to be no surface discharge from each lot which could affect stability
on landslip areas or cause erosion.

This addresses Items 10 and 11 of Council's Information Request.

SLR Consulting Australia Pty Ltd

Page 29

Kenlynn Pty Ltd Report Number 620.12166-R01

Castaways Beach 3 November 2017
Stormwater Management Plan Version v0.1
Page 9

 

3 WATER QUALITY ANALYSIS
3.1 Overview

As discussed in Section 2.1, it is proposed to construct a basin(s) within each lot to receive the
stormwater runoff from that lot.

As demonstrated in Section 2.4, the basin(s) will be sufficient to capture the runoff from all events up
to and including the 1% AEP flood event

The performance of the basin(s) in treating the stormwater runoff from each lot was therefore analysed
using MUSIC.

3.2 MUSIC Model

A MUSIC model of a typical 1,000 m? allotment was setup, including the proposed bioretention basin
at the downstream end of the lot. The layout of the MUSIC model is shown in Image 2.

 

©)

Urban [Mixed]

 

 

 
 
   

 

Bioretention
Receiving Node

Image 2. MUSIC Model Layout

A mixed catchment approach was adopted, using six minute rainfall data from Cooroy station
(#40059) in the analysis, in accordance with MUSIC Modelling Guidelines (Version 1.0 — 2010).

The Urban node comprised an area of 0.1 ha, and a fraction impervious of 60%. Standard parameters
for the Rainfall-Runoff and Pollutant Concentrations were adopted, in accordance with the MUSIC
Modelling Guidelines.
The properties of the bioretention basin were as follows:

e High Flow Bypass = 0.082 m*/s

e Extended detention Depth = 0.3 m

e Surface Area = 100 m?

e Filter Area = 100 m?

e Unlined Filter Media Perimeter = 50 metres

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Kenlynn Pty Ltd Report Number 620.12166-R01

Castaways Beach 3 November 2017
Stormwater Management Plan Version v0.1
Page 10

 

e Saturated Hydraulic Conductivity = 180 mm/h
e Exfiltration Rate = 180 mm/h
e Filter Depth = 0.5 metres

Default values were adopted for the TN Content of Filter Media (800 mg/kg) and the Orthophosphate
Content of the Filter Media (55 mg/kg).

The adopted infiltration rate of 180 mm/h is significantly lower than the value used for the hydrologic
analysis (as discussed in Section 2.4). Thus, the MUSIC analysis is considered to be conservative.

It is noted that the size of the bioretention basin is large compared to the size of the contributing
catchment, being 100/1000, or 10% of the catchment. In comparison, a typical bioretention basin
which complies with the load reduction targets for Queensland is 1.5% of the contributing catchment
area. Thus, the proposed bioretention basins are in the order of 6.7 times their required size.

The results of the MUSIC model analysis are shown in Table 2.

Table 2 MUSIC Model Results

 

 

 

 

 

Pollutant Source Load Residual Load Reduction Water Quality
(kglyr) (kg/yr) Achieved Objective
Total Suspended Solids 192 0.3 99.8% 80%
Total Phosphorus 0.38 0.00098 99.7% 60%
Total Nitrogen 22.8 0.00761 99.6% 45%
Gross Pollutant 22.8 0 400% 90%

 

These results demonstrate that the bioretention basins provide acceptable outcomes in relation to the
water quality treatment of each proposed allotment, and hence addresses Item 9 of Council's
Information Request.

SLR Consulting Australia Pty Ltd

 

Page 31

Kenlynn Pty Ltd Report Number 620.12166-R01

 

Castaways Beach 3 November 2017
Stormwater Management Plan Version v0.1

Page 11
4 CONCLUSION

It is proposed to construct a six lot subdivision on the subject site at 2 David Low Way, Castaways
Beach.

It is proposed to regrade the developable area within each lot in one of the following ways:
* Scenario 1 — high point at David Low Way, and lot falls to its eastern boundary; or

e Scenario 2 — high point in the middle of the lot, and the lot falls both to its eastern and western
boundaries.

The basin(s) will capture and infiltrate the stormwater runoff from all events up to and including the 1%
AEP flood event.

Consequently:

e the proposed development will meet the environmental objectives for water quality
management as required by the SPP and The Noosa Plan; and

e the proposed stormwater discharge strategy will not affect stability on landslip areas or cause
erosion.

SLR Consulting Australia Pty Ltd

 

Page 32

Appendix A
Castaways Beach
Stormwater Management Plan

 

Report Number 620.12166-RO1
3 November 2017

Version v0.1

Page 12

APPENDIX A

SUBDIVISION PROPOSAL PLAN

SLR Consulting Australia Pty Ltd

Page 33

 

 

 

 

This plan has been prepared as a proposed subdivision
and should not be used for any other purpose.

The dimensions, areas and total number of lots shown
hereon are subject to field survey and are also to the
requirements of council and any other authority which
may have requirements under any relevant legislation.
Certificate of Title for this site has not been obtained
Therefore, no reliance should be placed on the
information on this plan for any financial dealings
involving the land

 

 

iz

 

Covenant (Bushfire Risk and
Stormwater Management) Area

 

 

 

Environmental Covenant (Habitat Protection) Area

 

 

Building Envelope

=== New Road

  
 
   
    
   
   
 

fotal Area
F396 m2

Total Area
L807 m2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

   

 

SASAUNS STV

10 'd

ene LL

 

NA

   

PSLb PID ‘alepWNS |

NW1d 1VWSOdOdd NOISIAIGENS

 

 

 

 

 

 

Easement Schedule
Identifier Benefit Type
A 712 Access/Services/Council
B 711,713 Access/Services/Council
Cc 711,712,714 Access/Services/Council \
D 711-713,715 Access/Services/Council
E 711-714,716 Access/Services/Council
F 711-715 Access/Services/Council V
& Note:
Statistics Table Building Envelopes reflect
ue : — ; minimum building setbacks
fea rang? S42 = 3338 as per Schedule 1 of the
Area average 1601 m \ =:
Road 72m? Hh \\ Noosa Planning Scheme.
Park Nil
Covenant 5052 m* Contour Note:
Total Site Area 9677 m* Contour intervals are at 1.0m (minor) and 5.0m (major)
Scale 1:750 — Lengths are in Metres.
T REVISIONS Te L Josuil 1 L 1 L : . 1 1 ° 1 1 1 weal
} fe lo 0 10 20. 30 40 #250 #60 70 80 90 100 110
aumvevor Lea leave | ammo | LEVEL DATUM: |SITE: Proposed Lots 711-716 & Emt's A-F & Cov H,J-N & P-V. CLIENT: SCALE 4:750(A3)
craoni us fensexco vow | eewespmtrses SRT aap osumnt ence Kenlynn Pty Ltd =| pran rer: $0054-P5

 

 

 

 

 

 

 

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[OCR of page images]
CAD FILE->N\@500d5 \853I\ACAD\PLANNING\8531-8.d0g

PLOT DATE-> 06 Nov, 2017-4.40pm

 

LEGEND

DEVELOPMENT BOUNDARY
Q100 FLOOD LINE

CUT

FILL

RIPARIAN ZONE
VEGETATION LINE
EXISTING CONTOURS
DESIGN CONTOURS

TREE TO BE RETAINED

 

 

 

LAYOUT PLAN

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

° 15 20
SCALE foe 4500 (A1)
: 7 , DRAWING NUMBER:
© corner SURVEYOR: CLIENT PROIET: ae ee aon Siaaehae PLANNING
DESIGNED:
SERS 2 DAVID LOW War, ee REPARTNERS 8531-B
Seyi of Te De KENLYNN PTY LTD RaW 38 Eee BULK EARTHWORKS FULL Seat
WRITTEN PERMISSION OF SHEEHY CASTAWAYS BEACH 2 [DRIVEWAY REVISED nov'7 | RT Foeckep. PM —DW STRUCTURAL AND CIVIL LAYOUT PLAN 1 2] l l l l
Tee ere coe oa 1 [DRIVEWAY REVISED AND TURNAROUND ADDED | ocT ‘17 | SB Firm HGT)BED9 Seee FaN(O7}898 S659 OF DRAWh
"AMENDMENTS DATE [INTIALS| DATE: JUNE “17 A.C.N.009 899 905 No. OF DRAWINGS:

 

 

 

 

 

 

 

 

 

 

 

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                                                    Member Firm


[OCR of page images]
CAD FILE->N\ 500d \853I\ACAD\PLANNING\8531-C.dwg

PLOT DATE-> 06 Nov, 2017-4.40pm

 

LEGEND

 

 

 

 

DEVELOPMENT BOUNDARY
Q100 FLOOD LINE
RIPARIAN ZONE
VEGETATION LINE
EXISTING CONTOURS
DESIGN CONTOURS

-2.0m to -3.0m

-2.0m to -1.0m

-1.0m to 0.0m

0.0m to 1.0m

1.0m to 2.0m

 

 

LAYOUT PLAN

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

° 15 20
SCALE foe 4500 (A1)

: 7 , DRAWING NUMBER:

© corner SURVEYOR: CLIENT PROIET: ae ee aon Siaaehae PLANNING
DESIGNED:

SERS 2 DAVID LOW War, reas [cornu REPARTNERS 8531-C
Seyi of Te De KENLYNN PTY LTD RaW 38 Eee BULK EARTHWORKS GRADATION PULL SEAN
WRITTEN PERMISSION OF SHEEHY CASTAWAYS BEACH 2 [DRIVEWAY REVISED nov'7 | RT Foeckep. PM —DW STRUCTURAL AND CIVIL LAYOUT PLAN 1 2] l l l l
Tee ere coe oa 1 [DRIVEWAY REVISED AND TURNAROUND ADDED | ocT ‘17 | SB Firm HGT)BED9 Seee FaN(O7}898 S659
INFRINGEMENT OF COPYRIGHT. “AMENDMENTS DATE TINTIALS | DATE JUNE “17 A.C.N.009 899 905 No. OF DRAWINGS: