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Amended Stormwater Plan
Attached to the e-mail Information Request Response REC16/0014.
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Log in to see the plans as drawnSITE BASED STORMWATER MANAGEMENT PLAN
For
Elkhorn Investments (QLD) Pty Ltd
Proposed Sub-division at
28 Elkhorn Drive,
Tewantin
Job Ref: SC- 5551
Revision C
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Page 2
SC5551 - 28 Elkhorn Dr, Tewantin 1
AUTHORSHIP INFORMATION
Site Based Stormwater
REPORT TITLE
Management Plan
Affected
Properties
Street Address 28 Elkhorn Drive, Tewantin
RP Description Lot 70 M37807
Prepared For Elkhorn Investments (QLD) Pty Ltd
Date March 2016
Report Status For DA Approval
Prepared By
Name Matt Johnson
Qualifications BE (Civil)
Company Empire Engineering Pty Ltd
Phone Number 07 5477 6437
Reviewed By
Name Sean Dwyer
Qualifications BE (Civil)
Approved By
Name Troy Paulsen
Qualifications BE (Civil), CPEng, RPEQ 6990
REVISION DATE Reviewed/ Approval
A 21.03.16 T.Paulsen
B 06.06.16 T.Paulsen
C 26.10.16
Document Qualifying and Ownership Statement:
The contents of this document represent an assessment of the facts and circumstances pertaining to this
matter, as they are known to the writer at the time of preparation. It is possible that upon completion and
distribution of this document further information may come to hand that impact upon the findings,
recommendations or conclusions drawn in this document. This document and its contents remains the
property of Empire Engineering and cannot be reproduced in whole or in part for any reasons that could be
considered to be outside the exact, intended original use of this document.
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SC5551 - 28 Elkhorn Dr, Tewantin 2
TABLE OF CONTENTS
1.0 Introduction ............................................................................................................. 3
1.1 Background ......................................................................................................... 3
1.2 Scope .................................................................................................................. 3
1.3 Existing Topography ............................................................................................ 3
1.4 Proposed Development........................................................................................ 4
2.0 Water Cycle Management ....................................................................................... 5
2.1 Background ......................................................................................................... 5
2.2 Wastewater Minimisation ..................................................................................... 5
2.3 Stormwater Harvesting Tanks .............................................................................. 5
3.0 Water Quality Management .................................................................................... 6
3.1 Background ......................................................................................................... 6
3.2 Construction Phase.............................................................................................. 6
3.3 Operational Phase ............................................................................................... 7
3.3.1 Water Quality Objectives.................................................................................. 7
3.3.2 Pollutant Export Modelling ............................................................................... 7
3.3.2.1 Rainfall Data................................................................................................ 8
3.3.2.2 Treatment Nodes ......................................................................................... 9
3.3.3 Effectiveness in Pollution Reduction................................................................. 9
4.0 Stormwater Quantity Management....................................................................... 10
4.1 Background ....................................................................................................... 10
4.2 Site Drainage Constraints and Opportunities ...................................................... 10
4.2.1 Drainage Constraints ..................................................................................... 10
4.2.2 Drainage Opportunities .................................................................................. 10
4.3 Modelling Overview............................................................................................ 12
4.3.1 Methodology .................................................................................................. 12
4.3.2 Catchment Areas ........................................................................................... 12
4.2.1 Peak Flow Rates ........................................................................................... 14
5.0 Conclusions .......................................................................................................... 16
APPENDIX A – STORMWATER MANAGEMENT PLAN..................................................... 17
APPENDIX B – STORMWATER QUALITY MUSIC MODELLING ....................................... 18
APPENDIX C – RATIONAL METHOD CALUCATIONS ...................................................... 21
APPENDIX D – WATER SENSITIVE DESIGN CODE ASSESSMENT ................................ 22
Page 4
SC5551 - 28 Elkhorn Dr, Tewantin 3 1.0 Introduction 1.1 Background This report is to accompany and be considered part of an application to Noosa Council for a proposed sub- division at 28 Elkhorn Dr, Tewantin. 1.2 Scope Empire Engineering Pty Ltd was commissioned by Elkhorn Investments (QLD) Pty Ltd to develop a site based Stormwater Management Plan (SWMP) to outline water management strategies for the proposed development that will comply with Council’s relevant planning scheme policies, Queensland Development Code and the Environmental Protection Act (1994) and associated Environmental Protection (Water) Policy 1997. This report presents the results of a SWMP and outlines the proposed measures to be adopted in relation to stormwater quality management and stormwater quantity management for the subject site and the proposed development. 1.3 Existing Topography The subject site is described as Lot 70 M37807 with a combined area of 12,938m2. The site is bounded by Elkhorn Drive and existing residential allotments to the south, existing residential allotments to the west and north, and Noosa River Esplanade to the east. The site is currently occupied by a single residential house with an associated shed. The remainder of the lot is covered in grass and tree/shrubbery. See Figure 1.1.
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SC5551 - 28 Elkhorn Dr, Tewantin 4
Subject Site:
28 Elkhorn Dr,
Tewantin
N
Figure 1.1 Subject Site
The site has a crest approximately 45m off the eastern boundary on the southern end of the site, to
approximately 25m off the eastern boundary at the northern end of the site. This crest is at approximately
RL10.25. The site falls to the west at approximately 2.5% grade to almost RL8.25 in the south-western
corner. The site also falls to the east at approximately 18% to RL2.00 in the south-eastern corner. Under
existing conditions rainfall sheet flows from the site’s crest into either the Noosa River or the adjacent
residential property.
1.4 Proposed Development
Preliminary drawings prepared by KHA Development Managers depict a proposed 11 lot residential sub-
division and associated road.
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SC5551 - 28 Elkhorn Dr, Tewantin 5
2.0 Water Cycle Management
2.1 Background
The purpose of this section of the SWMP is to outline water saving measures that will be implemented in
the design and construction of the proposed development.
2.2 Wastewater Minimisation
To reduce the impact of water demand from the development and to minimise the loading on the existing
sewerage network, it is intended to reduce the wastewater leaving the site through the use of “at source”
measures. This will include:
Water saving shower roses with a AAA rating or better
Dual flush toilet cisterns that do not exceed 6 litres on full flush and 3 litres on half flush
The use of 3 star (or higher) water efficient appliances
2.3 Stormwater Harvesting Tanks
The developer has not opted in to stormwater harvesting tanks.
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SC5551 - 28 Elkhorn Dr, Tewantin 6
3.0 Water Quality Management
3.1 Background
A requirement of the proposed development is that Stormwater quality treatment shall be provided to meet
the design objectives set out in Section 2.4 of DERM’s Urban Stormwater Quality Planning guidelines 2010
and the associated with State Planning Policy (SPP) 4/10 Healthy Waters. The scope typically
encompasses the ‘post construction’ phase of the development however ‘construction phase’ water quality
is briefly addressed.
3.2 Construction Phase
Table 3.1 has been adapted from Table C4.1 of Brisbane City Council’s (BCC) Stormwater Best
Management Practices 2000 and details the typical stormwater pollutants which may be generated during
the construction phase of the development.
Pollutant Sources
Litter Paper, construction packaging, food packaging,
cement bags and off-cuts
Sediment Unprotected exposed soils and stockpiles during
earthworks and building
Hydrocarbons Fuel and oil spills, leaks from construction equipment
Toxic Materials Cement slurry, solvents, cleaning agents, wash waters
pH Altering Substances Cement slurry, wash waters
Table 3.1 –Typical Construction Phase Pollutants
The following measures should typically be implemented prior to the commencement of
construction:
Education of all site workers in sediment and erosion procedures
Specified storage areas for construction materials and plant that are bunded to prevent
any spillages from escaping
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SC5551 - 28 Elkhorn Dr, Tewantin 7
During the construction phase of the development, silt fences should be erected downstream of all
disturbed areas. In addition erosion and sediment control devices should be regularly inspected and
maintained following storm events. An Erosion and Sediment Control Plan will be provided as part of the
operational works application.
3.3 Operational Phase
During the operational stage of the development, the following impacts have been identified in relation to
stormwater runoff and water quality of the receiving waterways:
Gross pollutants which include human derived litter, course sediment and vegetation
Sediment and suspended solids
Nutrients such as phosphorous and nitrogen
To target these potential pollutants stormwater quality improvement devices (SQID’s) are proposed to be
incorporated within the design.
3.3.1 Water Quality Objectives
The water quality objectives (WQO’s) for this site were determined in accordance with Appendix 2 of the
State Planning Policy (SPP) Dec 2013.
Table 3.2 indicates the minimum load reduction targets required to be met:
Pollutant Minimum Reduction Targets
Total Suspended Sediments (TSS) 80%
Total Phosphorus (TP) 60%
Total Nitrogen (TN) 45%
Gross Pollutants (>5mm) 90%
Table 3.2 - Water Quality Objectives
3.3.2 Pollutant Export Modelling
The Model for Urban Stormwater Improvement Conceptualisation (MUSIC) has been utilised to calculate
pollutant loads from the proposed development and to predict performance characteristics of the proposed
treatment train. The pollutants have been generated stochastically and modelling parameters used were
adopted from the Water by Design “Music Modelling Guidelines for South-East Queensland”, and the
updated MUSIC Version 5 recommended parameters for Bio-retention basin nodes. MUSIC modelling
setup and results are attached within Appendix B.
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SC5551 - 28 Elkhorn Dr, Tewantin 8
Under the proposed conditions, the site was ‘split’ into three land use catchment nodes; the roofed area,
driveways and ground level uses. The pollutant export parameters utilised were based on the Urban
Residential pollutant loads, refer Table 3.3 & 3.4.
Parameter Value
Rainfall threshold (mm) 1
Soil storage capacity (mm) 500
Initial storage (% capacity) 10
Field capacity (mm) 200
Infiltration capacity coefficient (a) 211
Infiltration capacity exponent (b) 5.0
Initial depth (mm) 50
Daily recharge rate (%) 28
Daily baseflow rate (%) 27
Daily deep seepage rate (%) 0
Table 3.3 – Rainfall-runoff Parameters Adopted (Urban Residential)
TSS Log TP Log TN Log
Flow Type Surface Type
Mean Std Dev. Mean Std Dev. Mean Std Dev.
Roof N/A N/A N/A N/A N/A N/A
Baseflow
Driveways 1.00 0.34 -0.97 0.31 0.20 0.20
Parameters
Ground Level 1.00 0.39 -0.97 0.31 0.20 0.20
Roof 1.30 0.39 -0.89 0.31 0.26 0.23
Stormflow
Driveways 2.43 0.39 -0.30 0.31 0.26 0.23
Parameters
Ground Level 2.18 0.39 -0.47 0.31 0.26 0.23
Table 3.4 – Pollutant Export Values Adopted (Urban Residential)
3.3.2.1 Rainfall Data
Rainfall data for the site was chosen to give the best representation of actual conditions. A time period of
10 years between 1973 and 1983 was selected from the Cooroy Composite station, using a six minute time
step.
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SC5551 - 28 Elkhorn Dr, Tewantin 9
3.3.2.2 Treatment Nodes
The following devices have been used in the treatment train to reduce these pollutant loads to achieve WQO’s
before discharging into the Elkhorn Drive drainage system.
Bio-Retention Basin – An area of 70m2 designated Bio-retention to treat road, landscape, and roof
catchments to achieve the WQO’s was modelled. An extended detention depth of 200mm with a filter
media of 200mm/hr sandy loam hydraulic conductivity has been modelled. The location of this device
is shown on the attached Appendix A.
3.3.3 Effectiveness in Pollution Reduction
The water quality development model was set up with the incorporation of the above devices to reduce
pollutant export to WQO levels. Table 3.5 indicates the predicted pollutant mean values of stormwater
discharged from the site as calculated by MUSIC:
Pollutant Percentage Load Reduction
Total Suspended Solids (TSS) 82.8%
Total Phosphorus (TP) 62.4%
Total Nitrogen (TN) 49.9%
Gross Pollutants (>5mm) 100%
Table 3.5 - Flow Based Pollutant Load Reduction
The MUSIC modelling results shown above indicate that the treatment train will adequately treat TSS, TP
and TN generated by stormwater runoff in accordance with the targets required under the water quality
objectives stated previously.
Page 11
SC5551 - 28 Elkhorn Dr, Tewantin 10 4.0 Stormwater Quantity Management 4.1 Background The proposed sub-division and associated increase in impervious areas has the potential to create or exacerbate drainage problems to downstream areas and/or drainage infrastructure. The purpose of this section of the SWMP is to determine the general requirements for bulk stormwater management for the proposed development. The design shall ensure that rainfall event discharges are conveyed from the site in a manner that complies with Council’s stormwater planning guidelines and does not result in a worsened drainage situation to downstream infrastructure, without causing a nuisance or annoyance to residents/property owners. Under existing conditions the subject site has a catchment crest beginning approximately 88m east off the south-western corner, to approximately 36m east off the north-western corner. The western portion of the catchment sheet flows over the west boundary into the neighbouring lot. The eastern portion of the catchment sheet flows east into Noosa River Esplanade. Refer to Figure 4.1 on the following page. 4.2 Site Drainage Constraints and Opportunities 4.2.1 Drainage Constraints No lawful point of discharge exists to the downstream western or eastern properties. Earthworks to the western boundary to achieve grade out to the new road must be minimised to avoid large height retaining walls. 4.2.2 Drainage Opportunities It is proposed to discharge all roof areas to a lawful point of discharge (the new road kerb and channel), and the new road will provide a formal underground drainage downstream to an existing connection in Elkhorn Drive. Ground areas of Lots 1-5 will sheet flow over the western boundary, and ground areas of Lots 6-11 will sheet flow into the new road. The drainage system from Elkhorn Drive to Noosa River Esplanade will be upgraded to cater for the proposed development. This proposal will ensure a situation of non-worsening discharge to the downstream boundary conditions.
Page 12
SC5551 - 28 Elkhorn Dr, Tewantin 11
SITE
FALL
FALL
N
Figure 4.1 – Existing Drainage Paths
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Figure 4.1 — Existing Drainage Paths
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SC5551 - 28 Elkhorn Dr, Tewantin 12
4.3 Modelling Overview
4.3.1 Methodology
A Rational Method calculation was conducted to determine that a situation of non-worsening could be
achieved to the downstream (east and west) boundary conditions. The results from a Rational Method
calculation are illustrated in Table 4.3. Full Rational Method calculations have been provided in Appendix
C. Table 4.2 illustrates a large portion of the proposed development will discharge to the existing Elkhorn
Drive drainage system. This is proposed to be upgraded in order to cater for the additional catchment. The
proposed upgrade has been provided in Appendix A.
4.3.2 Catchment Areas
Pre-development and Post-development catchment areas have been provided in Appendix A and below in
Table 4.1 and 4.2. The catchment areas have been significantly reduced for the western boundary
compared to the pre-development scenario. The eastern boundary catchment has remained the same
compared to the pre-development scenario. An additional catchment to Elkhorn Drive is proposed,
requiring upgrades as discussed previously.
Catchment Name Description % Impervious Area (Ha)
Roof 100 0.020
‘A’
Landscape 0 0.302
‘B’ Landscape 0 0.136
‘C’ Landscape 0 0.115
‘D’ Landscape 0 0.094
‘E’ Landscape 0 0.153
‘F’ Landscape 0 0.076
Western Boundary Total Catchment (ha) 2 0.897
Roof 100 0.032
‘G’
Landscape 0 0.366
Eastern Boundary Total Catchment (ha) 0 0.398
Table 4.1 – Pre-Development Catchment Areas
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SC5551 - 28 Elkhorn Dr, Tewantin 13
‘A’ Roof 100 0.018
‘B’ Roof 100 0.018
‘C’ Roof 100 0.018
‘D’ Roof 100 0.018
‘E’ Roof 100 0.018
Roof 100 0.018
‘F’ Hardstand 100 0.030
Landscape 0 0.012
Roof 100 0.018
‘H’ Hardstand 100 0.030
Landscape 0 0.012
Roof 100 0.018
‘I’ Hardstand 100 0.030
Landscape 0 0.012
Roof 100 0.020
‘J’
Landscape 0 0.071
Roof 100 0.018
‘K’ Hardstand 100 0.014
Landscape 0 0.008
Roof 100 0.018
‘L’ Hardstand 100 0.015
Landscape 0 0.011
Road 100 0.118
‘M’
Landscape 0 0.078
Elkhorn Dr Total Catchment (Ha) 70 0.641
Roof 100 0.032
‘G’
Landscape 0 0.366
Eastern Boundary Total Catchment (Ha) 8 0.398
Table 4.2 – Post-Development Catchment Areas
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SC5551 - 28 Elkhorn Dr, Tewantin 14
Catchment Name Description % Impervious Area (Ha)
Hardstand 100 0.046
‘A’
Landscape 0 0.016
Hardstand 100 0.043
‘B’
Landscape 0 0.015
Hardstand 100 0.039
‘C’
Landscape 0 0.015
Hardstand 100 0.031
‘D’
Landscape 0 0.012
Hardstand 100 0.030
‘E’
Landscape 0 0.012
Western Boundary Total Catchment (Ha) 70 0.259
Table 4.2 – Post-Development Catchment Areas (Cont’d)
4.2.1 Peak Flow Rates
The results in Table 4.3 & 4.4 demonstrate that a situation of non-worsening can be achieved to both the
east and west downstream boundary conditions. Refer to Appendix A for details.
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3
Storm Flow Rate to Catchment Boundary (m /s)
Event Western Eastern
‘A’ ‘B’ ‘C’ ‘D’ ‘E’ ‘F’ ‘G’
39% AEP 0.039 0.016 0.014 0.012 0.019 0.01 0.066
Q2 ARI
18% AEP 0.052 0.022 0.019 0.016 0.026 0.014 0.089
Q5 ARI
10% AEP 0.072 0.03 0.026 0.022 0.036 0.019 0.123
Q10 ARI
5% AEP 0.084 0.035 0.031 0.026 0.042 0.022 0.144
Q20 ARI
2% AEP 0.101 0.042 0.037 0.03 0.05 0.027 0.172
Q50 ARI
1% AEP 0.128 0.053 0.047 0.039 0.064 0.034 0.217
Q100 ARI
Table 4.3 – Pre-Development Peak Flow
3
Storm Flow Rate to Catchment Boundary (m /s)
Event Western Eastern
‘A’ ‘B’ ‘C’ ‘D’ ‘E’ ‘F’ ‘G’
39% AEP 0.015 0.012 0.01 0.005 0.01 0 0.059
Q2 ARI
18% AEP 0.02 0.016 0.013 0.006 0.014 0 0.08
Q5 ARI
10% AEP 0.028 0.021 0.018 0.009 0.019 0 0.111
Q10 ARI
5% AEP 0.033 0.025 0.021 0.01 0.022 0 0.129
Q20 ARI
2% AEP 0.041 0.032 0.027 0.01 0.028 0 0.154
Q50 ARI
1% AEP 0.054 0.042 0.036 0.01 0.038 0 0.195
Q100 ARI
Table 4.4 – Post-Development Peak Flow
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SC5551 - 28 Elkhorn Dr, Tewantin 16
5.0 Conclusions
This report has outlined a total water cycle strategy to be adopted in the construction and operational
works phase of the development which satisfies the acceptable solutions set out in Councils planning
scheme policies.
Wastewater minimisation strategies will be adopted to reduce the demand on Council’s existing
infrastructure,
Best practice and practical water quality improvement devices are proposed which include a Bio-
retention Basin areas totalling 70m 2,
A situation of non-worsening can be achieved to the downstream boundary conditions. This is
achieved by reducing the existing catchment areas to the west, maintaining existing conditions to
the east, and providing a formal underground drainage system to an existing manhole in Elkhorn
Drive. The existing manhole in Elkhorn Drive to the outlet into Noosa River Esplanade will require
upgrading to cater for the additional catchment.
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SC5551 - 28 Elkhorn Dr, Tewantin 17
APPENDIX A – STORMWATER MANAGEMENT PLAN
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17
APPENDIX A — STORMWATER MANAGEMENT PLAN
Page 19
LEGEND
SECTION
CONCEPT STORMWATER MANAGEMENT PLAN
Bundaberg Gladstone Sunshine Coast
EMP RE
ENGINEERING
9 Princess Street Bundaberg Qld
PO Box 2052 Bundaberg Qld 4670
T: 07 4154 4894 F: 07 4154 4274
E: [email protected]
4 Goondoon Street Gladstone Qld
PO Box 1743 Gladstone DC Qld 4680
T: 07 4972 5387
E: [email protected]
45 Brisbane Road Mooloolaba Qld
PO Box 102 Mooloolaba Qld 4557
T: 07 5477 6437 F: 07 5444 4216
E: [email protected]
ACN 112761510 ABN 21112761510
Page 20
LEGEND
SW
SW
SW
STORMWATER DRAINAGE NETWORK UPGRADES
Bundaberg Gladstone Sunshine Coast
EMP RE
ENGINEERING
9 Princess Street Bundaberg Qld
PO Box 2052 Bundaberg Qld 4670
T: 07 4154 4894 F: 07 4154 4274
E: [email protected]
4 Goondoon Street Gladstone Qld
PO Box 1743 Gladstone DC Qld 4680
T: 07 4972 5387
E: [email protected]
45 Brisbane Road Mooloolaba Qld
PO Box 102 Mooloolaba Qld 4557
T: 07 5477 6437 F: 07 5444 4216
E: [email protected]
ACN 112761510 ABN 21112761510
Page 21
LEGEND
PRE-DEVELOPMENT CATCHMENT PLAN
Bundaberg Gladstone Sunshine Coast
EMP RE
ENGINEERING
9 Princess Street Bundaberg Qld
PO Box 2052 Bundaberg Qld 4670
T: 07 4154 4894 F: 07 4154 4274
E: [email protected]
4 Goondoon Street Gladstone Qld
PO Box 1743 Gladstone DC Qld 4680
T: 07 4972 5387
E: [email protected]
45 Brisbane Road Mooloolaba Qld
PO Box 102 Mooloolaba Qld 4557
T: 07 5477 6437 F: 07 5444 4216
E: [email protected]
ACN 112761510 ABN 21112761510
Page 22
PRE-DEVELOPMENT DRAINAGE LONGITUDINAL SECTION
Bundaberg Gladstone Sunshine Coast
EMP RE
ENGINEERING
9 Princess Street Bundaberg Qld
PO Box 2052 Bundaberg Qld 4670
T: 07 4154 4894 F: 07 4154 4274
E: [email protected]
4 Goondoon Street Gladstone Qld
PO Box 1743 Gladstone DC Qld 4680
T: 07 4972 5387
E: [email protected]
45 Brisbane Road Mooloolaba Qld
PO Box 102 Mooloolaba Qld 4557
T: 07 5477 6437 F: 07 5444 4216
E: [email protected]
ACN 112761510 ABN 21112761510
Page 23
LEGEND
SW
SW
SW
POST-DEVELOPMENT CATCHMENT PLAN
Bundaberg Gladstone Sunshine Coast
EMP RE
ENGINEERING
9 Princess Street Bundaberg Qld
PO Box 2052 Bundaberg Qld 4670
T: 07 4154 4894 F: 07 4154 4274
E: [email protected]
4 Goondoon Street Gladstone Qld
PO Box 1743 Gladstone DC Qld 4680
T: 07 4972 5387
E: [email protected]
45 Brisbane Road Mooloolaba Qld
PO Box 102 Mooloolaba Qld 4557
T: 07 5477 6437 F: 07 5444 4216
E: [email protected]
ACN 112761510 ABN 21112761510
Page 24
POST-DEVELOPMENT DRAINAGE LONGITUDINAL SECTION
Bundaberg Gladstone Sunshine Coast
EMP RE
ENGINEERING
9 Princess Street Bundaberg Qld
PO Box 2052 Bundaberg Qld 4670
T: 07 4154 4894 F: 07 4154 4274
E: [email protected]
4 Goondoon Street Gladstone Qld
PO Box 1743 Gladstone DC Qld 4680
T: 07 4972 5387
E: [email protected]
45 Brisbane Road Mooloolaba Qld
PO Box 102 Mooloolaba Qld 4557
T: 07 5477 6437 F: 07 5444 4216
E: [email protected]
ACN 112761510 ABN 21112761510
Page 25
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APPENDIX B – STORMWATER QUALITY MUSIC MODELLING
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APPENDIX B —- STORMWATER QUALITY MUSIC MODELLING
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Figure B.1 – MUSIC Model Node Layout
Figure B.2 – MUSIC Model Treatment Train Effectiveness
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Figure B.3 – MUSIC Model ‘Bio-retention’ Node
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20
| Inlet Properties
Low Flow By-pass (cubic metres per sec)
High Flow By-pass (cubic metres per sec)
;~ Storage Properties
Extended Detention Depth (metres)
Surface Area (square metres)
Filter and Media Properties
Filter Area (square metres)
Unlined Filter Media Perimeter (metres)
Saturated Hydraulic Conductivity (mm/hour)
Filter Depth (metres)
TN Content of Filter Media (mg/kg)
Orthophosphate Content of Filter Media (mg/kg)
epee Pe
Is Base Lined? (¥] Yes [7] No
‘Vegetation Properties
© Vegetated with Effective Nutrient Removal Plants
© Vegetated with Ineffective Nutrient Removal Plants
© Unvegetated
—Infitration Properties
Egittration Rate (mm/hr)
Outlet Properties
Overflow Weir Width (metres) 2.40
Underdrain Present? Yes [|] No
Yes No
0.00
ce Lae J
| cance || <Back || W Brish |
Figure B.3 — MUSIC Model ‘Bio-retention’ Node
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APPENDIX C – RATIONAL METHOD CALUCATIONS
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APPENDIX C — RATIONAL METHOD CALUCATIONS
Page 29
Catchment (A) Rational Method Analysis
Site Location:
Tewantin
Q = CIA/360 IFD data from BOM
Where: DURATION1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 129.00 164.00 202.00 223.00 253.00 291.00 321.00
C = Coefficient of discharge 6Mins 121.00 154.00 189.00 210.00 238.00 275.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 99.30 126.00 156.00 173.00 196.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.10 92.90 115.00 128.00 145.00 168.00 185.00
30Mins 59.70 76.00 94.20 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.40 51.60 64.70 72.30 82.70 96.30 107.00
Tc calculated by Friends Equation 2Hrs 25.90 33.40 42.80 48.40 55.90 65.90 73.50
3Hrs 19.60 25.50 33.20 37.90 44.10 52.50 58.90
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.20 16.00 21.50 25.00 29.50 35.60 40.40
Where: 12Hrs 7.72 10.20 14.10 16.60 19.90 24.30 27.90
n = Hortons surface roughness factor 24Hrs 5.09 6.78 9.51 11.30 13.60 16.70 19.30
L = overland sheet flow path length 48Hrs 3.37 4.51 6.38 7.61 9.18 11.40 13.10
S = slope of surface (%) 72Hrs 2.54 3.41 4.88 5.86 7.10 8.83 10.20
Existing Developed Existing Developed
Tc (mins) 17.8 5 n 0.045
L 88
Therefore intensities (I) using Tc are as follows: S 2.5
Tc = (mins) 17.8 5.0 **Standard inlet time adopted
ARI Existing Developed
1 77.23 129.00
2 98.15 164.00
5 121.44 202.00
10 134.68 223.00
20 153.04 253.00
50 177.07 291.00
100 195.27 321.00
1 hour 10 year intensity (1I10)=
72.30
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing Developed
Area (ha) 0.3224 0.0801 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 0 0.8
C10 0.7 0.86 ARI Frequency factor (Fy)
C1 0.560 0.688 1 0.8
C2 0.595 0.731 2 0.85
C5 0.665 0.817 5 0.95
C10 0.700 0.860 10 1
C20 0.735 0.903 20 1.05
C50 0.805 0.989 50 1.15
C100 0.840 1.000 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing Developed Roof 180m2 Post (Minus Roof) % Change to Boundary
1 0.039 0.020 0.005 0.015 -87.8%
2 0.052 0.027 0.006 0.020 -87.8%
5 0.072 0.037 0.009 0.028 -88.1%
10 0.084 0.043 0.010 0.033 -88.5%
20 0.101 0.051 0.010 0.041 -84.7%
50 0.128 0.064 0.010 0.054 -81.1%
100 0.147 0.071 0.010 0.061 -82.1%
Page 30
Catchment (B) Rational Method Analysis
Site Location:
Tewantin
Q = CIA/360 IFD data from BOM
Where: DURATION1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 129.00 164.00 202.00 223.00 253.00 291.00 321.00
C = Coefficient of discharge 6Mins 121.00 154.00 189.00 210.00 238.00 275.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 99.30 126.00 156.00 173.00 196.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.10 92.90 115.00 128.00 145.00 168.00 185.00
30Mins 59.70 76.00 94.20 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.40 51.60 64.70 72.30 82.70 96.30 107.00
Tc calculated by Friends Equation 2Hrs 25.90 33.40 42.80 48.40 55.90 65.90 73.50
3Hrs 19.60 25.50 33.20 37.90 44.10 52.50 58.90
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.20 16.00 21.50 25.00 29.50 35.60 40.40
Where: 12Hrs 7.72 10.20 14.10 16.60 19.90 24.30 27.90
n = Hortons surface roughness factor 24Hrs 5.09 6.78 9.51 11.30 13.60 16.70 19.30
L = overland sheet flow path length 48Hrs 3.37 4.51 6.38 7.61 9.18 11.40 13.10
S = slope of surface (%) 72Hrs 2.54 3.41 4.88 5.86 7.10 8.83 10.20
Existing Developed Existing Developed
Tc (mins) 17.6 5 n 0.045
L 85
Therefore intensities (I) using Tc are as follows: S 2.5
Tc = (mins) 17.6 5.0 **Standard inlet time adopted
ARI Existing Developed
1 76.04 129.00
2 96.64 164.00
5 119.58 202.00
10 132.63 223.00
20 150.71 253.00
50 174.38 291.00
100 192.31 321.00
1 hour 10 year intensity (1I10)=
72.30
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing Developed
Area (ha) 0.1361 0.0656 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 0 0.8
C10 0.7 0.86 ARI Frequency factor (Fy)
C1 0.560 0.688 1 0.8
C2 0.595 0.731 2 0.85
C5 0.665 0.817 5 0.95
C10 0.700 0.860 10 1
C20 0.735 0.903 20 1.05
C50 0.805 0.989 50 1.15
C100 0.840 1.000 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing Developed Roof 180m2 Post (Minus Roof) % Change to Boundary
1 0.016 0.016 0.005 0.012 -33.1%
2 0.022 0.022 0.006 0.016 -33.1%
5 0.030 0.030 0.009 0.021 -33.5%
10 0.035 0.035 0.010 0.025 -34.0%
20 0.042 0.042 0.010 0.032 -28.0%
50 0.053 0.052 0.010 0.042 -22.3%
100 0.061 0.058 0.010 0.048 -23.0%
Page 31
Catchment (C) Rational Method Analysis
Site Location:
Tewantin
Q = CIA/360 IFD data from BOM
Where: DURATION1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 129.00 164.00 202.00 223.00 253.00 291.00 321.00
C = Coefficient of discharge 6Mins 121.00 154.00 189.00 210.00 238.00 275.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 99.30 126.00 156.00 173.00 196.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.10 92.90 115.00 128.00 145.00 168.00 185.00
30Mins 59.70 76.00 94.20 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.40 51.60 64.70 72.30 82.70 96.30 107.00
Tc calculated by Friends Equation 2Hrs 25.90 33.40 42.80 48.40 55.90 65.90 73.50
3Hrs 19.60 25.50 33.20 37.90 44.10 52.50 58.90
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.20 16.00 21.50 25.00 29.50 35.60 40.40
Where: 12Hrs 7.72 10.20 14.10 16.60 19.90 24.30 27.90
n = Hortons surface roughness factor 24Hrs 5.09 6.78 9.51 11.30 13.60 16.70 19.30
L = overland sheet flow path length 48Hrs 3.37 4.51 6.38 7.61 9.18 11.40 13.10
S = slope of surface (%) 72Hrs 2.54 3.41 4.88 5.86 7.10 8.83 10.20
Existing Developed Existing Developed
Tc (mins) 16.9 5 n 0.045
L 75
Therefore intensities (I) using Tc are as follows: S 2.5
Tc = (mins) 16.9 5.0 **Standard inlet time adopted
ARI Existing Developed
1 79.14 129.00
2 100.57 164.00
5 124.43 202.00
10 137.99 223.00
20 156.79 253.00
50 181.40 291.00
100 200.04 321.00
1 hour 10 year intensity (1I10)=
72.30
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing Developed
Area (ha) 0.1149 0.058 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 0 0.8
C10 0.7 0.86 ARI Frequency factor (Fy)
C1 0.560 0.688 1 0.8
C2 0.595 0.731 2 0.85
C5 0.665 0.817 5 0.95
C10 0.700 0.860 10 1
C20 0.735 0.903 20 1.05
C50 0.805 0.989 50 1.15
C100 0.840 1.000 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing Developed Roof 180m2 Post (Minus Roof) % Change to Boundary
1 0.014 0.014 0.005 0.010 -37.7%
2 0.019 0.019 0.006 0.013 -37.7%
5 0.026 0.027 0.009 0.018 -38.1%
10 0.031 0.031 0.010 0.021 -38.6%
20 0.037 0.037 0.010 0.027 -31.4%
50 0.047 0.046 0.010 0.036 -24.7%
100 0.054 0.052 0.010 0.042 -25.0%
Page 32
Catchment (D) Rational Method Analysis
Site Location:
Tewantin
Q = CIA/360 IFD data from BOM
Where: DURATION1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 129.00 164.00 202.00 223.00 253.00 291.00 321.00
C = Coefficient of discharge 6Mins 121.00 154.00 189.00 210.00 238.00 275.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 99.30 126.00 156.00 173.00 196.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.10 92.90 115.00 128.00 145.00 168.00 185.00
30Mins 59.70 76.00 94.20 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.40 51.60 64.70 72.30 82.70 96.30 107.00
Tc calculated by Friends Equation 2Hrs 25.90 33.40 42.80 48.40 55.90 65.90 73.50
3Hrs 19.60 25.50 33.20 37.90 44.10 52.50 58.90
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.20 16.00 21.50 25.00 29.50 35.60 40.40
Where: 12Hrs 7.72 10.20 14.10 16.60 19.90 24.30 27.90
n = Hortons surface roughness factor 24Hrs 5.09 6.78 9.51 11.30 13.60 16.70 19.30
L = overland sheet flow path length 48Hrs 3.37 4.51 6.38 7.61 9.18 11.40 13.10
S = slope of surface (%) 72Hrs 2.54 3.41 4.88 5.86 7.10 8.83 10.20
Existing Developed Existing Developed
Tc (mins) 16.5 5 n 0.045
L 70
Therefore intensities (I) using Tc are as follows: S 2.5
Tc = (mins) 16.5 5.0 **Standard inlet time adopted
ARI Existing Developed
1 79.97 129.00
2 101.64 164.00
5 125.74 202.00
10 139.43 223.00
20 158.43 253.00
50 183.30 291.00
100 202.13 321.00
1 hour 10 year intensity (1I10)=
72.30
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing Developed
Area (ha) 0.0941 0.0482 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 0 0.8
C10 0.7 0.86 ARI Frequency factor (Fy)
C1 0.560 0.688 1 0.8
C2 0.595 0.731 2 0.85
C5 0.665 0.817 5 0.95
C10 0.700 0.860 10 1
C20 0.735 0.903 20 1.05
C50 0.805 0.989 50 1.15
C100 0.840 1.000 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing Developed Roof 180m2 Post (Minus Roof) % Change to Boundary
1 0.012 0.012 0.005 0.007 -47.2%
2 0.016 0.016 0.006 0.010 -47.1%
5 0.022 0.022 0.009 0.013 -47.5%
10 0.026 0.026 0.010 0.016 -48.0%
20 0.030 0.031 0.010 0.021 -38.8%
50 0.039 0.039 0.010 0.028 -30.0%
100 0.044 0.043 0.010 0.033 -29.6%
Page 33
Catchment (E) Rational Method Analysis
Site Location:
Tewantin
Q = CIA/360 IFD data from BOM
Where: DURATION1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 129.00 164.00 202.00 223.00 253.00 291.00 321.00
C = Coefficient of discharge 6Mins 121.00 154.00 189.00 210.00 238.00 275.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 99.30 126.00 156.00 173.00 196.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.10 92.90 115.00 128.00 145.00 168.00 185.00
30Mins 59.70 76.00 94.20 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.40 51.60 64.70 72.30 82.70 96.30 107.00
Tc calculated by Friends Equation 2Hrs 25.90 33.40 42.80 48.40 55.90 65.90 73.50
3Hrs 19.60 25.50 33.20 37.90 44.10 52.50 58.90
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.20 16.00 21.50 25.00 29.50 35.60 40.40
Where: 12Hrs 7.72 10.20 14.10 16.60 19.90 24.30 27.90
n = Hortons surface roughness factor 24Hrs 5.09 6.78 9.51 11.30 13.60 16.70 19.30
L = overland sheet flow path length 48Hrs 3.37 4.51 6.38 7.61 9.18 11.40 13.10
S = slope of surface (%) 72Hrs 2.54 3.41 4.88 5.86 7.10 8.83 10.20
Existing Developed Existing Developed
Tc (mins) 15.8 5 n 0.045
L 62
Therefore intensities (I) using Tc are as follows: S 2.5
Tc = (mins) 15.8 5.0 **Standard inlet time adopted
ARI Existing Developed
1 81.45 129.00
2 103.52 164.00
5 128.06 202.00
10 142.00 223.00
20 161.34 253.00
50 186.66 291.00
100 205.83 321.00
1 hour 10 year intensity (1I10)=
72.30
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing Developed
Area (ha) 0.1532 0.06 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 0 0.8
C10 0.7 0.86 ARI Frequency factor (Fy)
C1 0.560 0.688 1 0.8
C2 0.595 0.731 2 0.85
C5 0.665 0.817 5 0.95
C10 0.700 0.860 10 1
C20 0.735 0.903 20 1.05
C50 0.805 0.989 50 1.15
C100 0.840 1.000 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing Developed Roof 180m2 Post (Minus Roof) % Change to Boundary
1 0.019 0.015 0.005 0.010 -62.7%
2 0.026 0.020 0.006 0.014 -62.6%
5 0.036 0.028 0.009 0.019 -63.0%
10 0.042 0.032 0.010 0.022 -63.4%
20 0.050 0.038 0.010 0.028 -57.0%
50 0.064 0.048 0.010 0.038 -51.0%
100 0.074 0.054 0.010 0.044 -51.4%
Page 34
Catchment (F) Rational Method Analysis
Site Location:
Tewantin
Q = CIA/360 IFD data from BOM
Where: DURATION1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 129.00 164.00 202.00 223.00 253.00 291.00 321.00
C = Coefficient of discharge 6Mins 121.00 154.00 189.00 210.00 238.00 275.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 99.30 126.00 156.00 173.00 196.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.10 92.90 115.00 128.00 145.00 168.00 185.00
30Mins 59.70 76.00 94.20 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.40 51.60 64.70 72.30 82.70 96.30 107.00
Tc calculated by Friends Equation 2Hrs 25.90 33.40 42.80 48.40 55.90 65.90 73.50
3Hrs 19.60 25.50 33.20 37.90 44.10 52.50 58.90
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.20 16.00 21.50 25.00 29.50 35.60 40.40
Where: 12Hrs 7.72 10.20 14.10 16.60 19.90 24.30 27.90
n = Hortons surface roughness factor 24Hrs 5.09 6.78 9.51 11.30 13.60 16.70 19.30
L = overland sheet flow path length 48Hrs 3.37 4.51 6.38 7.61 9.18 11.40 13.10
S = slope of surface (%) 72Hrs 2.54 3.41 4.88 5.86 7.10 8.83 10.20
Existing Developed Existing Developed
Tc (mins) 13.9 5 n 0.045
L 42
Therefore intensities (I) using Tc are as follows: S 2.5
Tc = (mins) 13.9 5.0 **Standard inlet time adopted
ARI Existing Developed
1 86.29 129.00
2 109.67 164.00
5 135.65 202.00
10 150.39 223.00
20 170.87 253.00
50 197.68 291.00
100 217.97 321.00
1 hour 10 year intensity (1I10)=
72.30
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing Developed
Area (ha) 0.076 0 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 0 0
C10 0.7 0 ARI Frequency factor (Fy)
C1 0.560 0.000 1 0.8
C2 0.595 0.000 2 0.85
C5 0.665 0.000 5 0.95
C10 0.700 0.000 10 1
C20 0.735 0.000 20 1.05
C50 0.805 0.000 50 1.15
C100 0.840 0.000 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing Developed % Change to boundary
1 0.010 0.000 n/A
2 0.014 0.000 n/A
5 0.019 0.000 n/A
10 0.022 0.000 n/A
20 0.027 0.000 n/A
50 0.034 0.000 n/A
100 0.039 0.000 n/A
Page 35
Catchment (G) Rational Method Analysis
Site Location:
Tewantin
Q = CIA/360 IFD data from BOM
Where: DURATION1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 129.00 164.00 202.00 223.00 253.00 291.00 321.00
C = Coefficient of discharge 6Mins 121.00 154.00 189.00 210.00 238.00 275.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 99.30 126.00 156.00 173.00 196.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.10 92.90 115.00 128.00 145.00 168.00 185.00
30Mins 59.70 76.00 94.20 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.40 51.60 64.70 72.30 82.70 96.30 107.00
Tc calculated by Friends Equation 2Hrs 25.90 33.40 42.80 48.40 55.90 65.90 73.50
3Hrs 19.60 25.50 33.20 37.90 44.10 52.50 58.90
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.20 16.00 21.50 25.00 29.50 35.60 40.40
Where: 12Hrs 7.72 10.20 14.10 16.60 19.90 24.30 27.90
n = Hortons surface roughness factor 24Hrs 5.09 6.78 9.51 11.30 13.60 16.70 19.30
L = overland sheet flow path length 48Hrs 3.37 4.51 6.38 7.61 9.18 11.40 13.10
S = slope of surface (%) 72Hrs 2.54 3.41 4.88 5.86 7.10 8.83 10.20
Existing Developed Existing Developed
Tc (mins) 8.3 5 n 0.045
L 25
Therefore intensities (I) using Tc are as follows: S 14
Tc = (mins) 8.3 5.0 **Standard inlet time adopted
ARI Existing Developed
1 106.99 106.99
2 135.98 135.98
5 167.93 167.93
10 186.05 186.05
20 211.29 211.29
50 244.32 244.32
100 269.30 269.30
1 hour 10 year intensity (1I10)=
72.30
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing Developed
Area (ha) 0.398 0.357 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 0 0
C10 0.7 0.7 ARI Frequency factor (Fy)
C1 0.560 0.560 1 0.8
C2 0.595 0.595 2 0.85
C5 0.665 0.665 5 0.95
C10 0.700 0.700 10 1
C20 0.735 0.735 20 1.05
C50 0.805 0.805 50 1.15
C100 0.840 0.840 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing Developed % Change to Boundary
1 0.066 0.059 -10.9%
2 0.089 0.080 -10.9%
5 0.123 0.111 -10.9%
10 0.144 0.129 -10.9%
20 0.172 0.154 -10.9%
50 0.217 0.195 -10.9%
100 0.250 0.224 -10.9%
Page 36
SC5551 - 28 Elkhorn Dr, Tewantin 22 APPENDIX D – WATER SENSITIVE DESIGN CODE ASSESSMENT [OCR of page images] $C5551 - 28 Elkhorn Dr, Tewantin 22 APPENDIX D — WATER SENSITIVE DESIGN CODE ASSESSMENT
Page 37
SC5551 - 28 Elkhorn Dr, Tewantin 23
column 1 column 2 Outcome
Specific Outcomes Probable solutions (if code assessable) Provided
Water reuse S1.1 Development complies with the water S1.1 – Complies, refer SWMP
O1 Development uses a combination of detention quality standards in Table 2 of the SEQ
and retention systems to capture run-off from areas
on the site; Regional Plan Implementation Guideline No.
AND 7 for Water Sensitive Urban Design;
O2 Water storage devices must have sufficient
S2.1 No solution provided S2.1 – No stormwater harvesting is
capacity having regard to local rainfall pattern and proposed due to type of development and
the catchment area of roof or other hard standing Council preference
surface; S3.1 Captured water is plumbed to be
S3.1 – No stormwater harvesting is
available for all external uses including
proposed due to type of development and
AND gardening, irrigation, ponds, filling swimming Council preference
O3 Captured water is utilised for all non-potable pools and outdoor cleaning, as well as all
uses on site;
ground floor toilet cisterns and washing
machine cold taps;
Page 38
SC5551 - 28 Elkhorn Dr, Tewantin 24
column 1 column 2 Outcome
Specific Outcomes Probable solutions (if code assessable) Provided
AND
S3.2 – N/A
S3.2 Where the captured water is used for
AND toilet flushing and/or laundry use, an
automatic or manual interchange device that
allows alternate use of captured water or the
reticulated water supply is installed to
ensure that there is a continual supply of
water for sanitary flushing and laundry use.
O4 On-site detention does not adversely impact S4.1 No solution provided S4.1 – Detention is not required due to
proposed upgrades of the downstream
on water requirements downstream of the site drainage network
where the water is required to sustain the ecology
and hydrology of downstream systems
(environmental flows);
S5.1 – N/A
AND
O5 Within the Shire Business Centre site, as S5.1 No solution provided
shown on Map SBC, on-site detention measures
are contained within the developed areas of the
site, clear of drainage lines and Open Space
Precincts.
Page 39
SC5551 - 28 Elkhorn Dr, Tewantin 25
Run-off treatment S6.1 & S7.1 - Complies, refer SWMP
O6 Run-off that leaves the site is treated so as S6.1 & S7.1 Development complies with the
not to adversely impact on the ecology and
water quality standards in Table 2 of the
hydrology of downstream environmental flows;
SEQ Regional Plan Implementation
AND
Guideline No. 7 for Water Sensitive Urban
O7 Within the Shire Business Centre site, as
Design.
shown on Map SBC—
a) run-off treatment occurs within the site ; and
b) drainage lines are only used for final polishing
of run-off.
Town water supply connections S8.1 – N/A
O8 Backflow devices or similar systems ensure S8.1 A suitable backflow prevention device
water reuse facilities have no impact on the quality
of the town mains water. is installed to protect the potable water
within the reticulated water supply in
accordance with AS/NZS 3500:2003
Plumbing and Drainage.
Use of natural treatments and systems S9.1 & S10.1 - Complies, refer SWMP
O9 Natural treatment strategies, including grass S9.1 & S10.1 Development complies with
swales and bio-retention systems, vegetated
filtration strips and gross pollutant traps, are used the water quality standards in Table 2 of the
wherever practicable; SEQ Regional Plan Implementation
AND
O10 Within the Shire Business Centre, as shown Guideline No. 7 for Water Sensitive Urban
on Map SBC— where necessary, drainage lines are Design.
ecologically enhanced to ensure that the water
quality polishing functions are of high standard.