Council archive · source document
Amended Stormwater Plan · MCU18/0019
Attached to the e-mail Response to Info Request (Amended Proposal Plans Part 2 & Amended Stormwater Plan) - MCU18/0019.
Plans and drawings: the text below has words only, no drawings.
SITE BASED STORMWATER MANAGEMENT PLAN
For
KNOWLES GROUP
Proposed Aged Care Facility at
Goodchap St,
Noosa
Job Ref: SC- 7440
May 2018
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Page 2
SC7440 – Goodchap St, Noosa 1
AUTHORSHIP INFORMATION
Site Based Stormwater
REPORT TITLE
Management Plan
Affected
Properties
Street Address Goodchap St, Noosa
Lots 4-9 on RP138011 &
RP Description
Lots 13-17 RP151414
Prepared For Knowles Group
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 Troy Paulsen
Qualifications BE (Civil), CPEng, RPEQ 6990
Company Empire Engineering Pty Ltd
Phone Number 07 5477 6437
REVISION DATE Reviewed/ Approval
A 15.12.17 T.Paulsen
B 03.05.18
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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SC7440 – Goodchap St, Noosa 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
3.0 Water Quality Management .................................................................................... 5
3.1 Background ......................................................................................................... 5
3.2 Construction Phase.............................................................................................. 5
3.3 Operational Phase ............................................................................................... 6
3.3.1 Water Quality Objectives.................................................................................. 7
3.3.2 Catchment Areas ............................................................................................. 7
3.3.3 Pollutant Export Modelling ............................................................................... 7
3.3.3.1 Rainfall Data................................................................................................ 8
3.3.3.2 Treatment Nodes ......................................................................................... 9
3.3.4 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............................................................................................ 10
4.3.1 Methodology .................................................................................................. 10
4.3.2 Catchment Areas ........................................................................................... 11
4.3.3 Roughness Coefficients ................................................................................. 11
4.3.4 Storm Events ................................................................................................. 11
4.3.5 Outlet Condition ............................................................................................. 12
4.3.6 On-Site Detention .......................................................................................... 12
4.4 Modelling Results .............................................................................................. 13
4.5 Impacts on Existing Infrastructure ...................................................................... 14
5.0 Flood Hazard Overlay ........................................................................................... 18
6.0 Conclusions .......................................................................................................... 19
APPENDIX A – STORMWATER MANAGEMENT PLAN..................................................... 20
APPENDIX B – STORMWATER QUALITY MUSIC MODELLING ....................................... 21
APPENDIX C – XP-STORM MODELLING .......................................................................... 25
APPENDIX D – SPEL SPECIFICATIONS ........................................................................... 30
APPENDIX E – RATIONAL METHOD CALCULATIONS .................................................... 31
Page 4
SC7440 – Goodchap St, Noosa 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 aged care facility at Goodchap St, Noosa. 1.2 Scope Empire Engineering Pty Ltd was commissioned by Knowles Group Pty Ltd to develop a Site Based Stormwater Management Plan (SBSWMP) 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 Lots 4-9 on RP138011 & Lots 13-17 RP151414with a total area of 6,740m 2. The site is bounded by Good Chap Street to the north-east, Val Crescent to the north-west and south-west, and existing residential property boundaries to the south-east. See Figure 1.1.
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SC7440 – Goodchap St, Noosa 4
Subject Site:
Goodchap St,
Noosa
N
Figure 1.1 Subject Site
The site currently grades from east to west at approximately 5%. The allotments are existing residential
allotments each occupied by single dwellings. Underground stormwater infrastructure exists on Val
Crescent that is deemed the lawful point of discharge for the site.
1.4 Proposed Development
Schematic architectural drawings prepared by Elevation Architecture depict a aged care facility development
with associated driveway and basement car parking facilities.
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SC7440 – Goodchap St, Noosa 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
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.
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SC7440 – Goodchap St, Noosa 6
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
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.
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SC7440 – Goodchap St, Noosa 7
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 2016.
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 Catchment Areas
Table 3.3 illustrates the proposed roof, carpark/hardstand, and landscape areas to be treated as part of the
development site.
% Impervious
(Per MUSIC
Node Description Area (Ha)
Modelling
Guidelines)
Combined Roof 100 0.400
Post-development Carpark/hardstand areas 100 0.085
Catchments Landscape 25 0.189
Total MUSIC Model Catchment (Ha) 0.674
Table 3.3 - Post Development Sub–Catchment Areas
3.3.3 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. 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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SC7440 – Goodchap St, Noosa 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 Tables 3.4 & 3.5. The pollutants have been generated stochastically in the
modelling scenario.
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 3.4 – 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 0.34 -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 3.5 – Pollutant Export Values Adopted (Urban Residential)
3.3.3.1 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. The Mean Annual Rainfall for this period is 1595mm, and the Mean Annual ET is 1201mm. See
attached Appendix B for details.
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SC7440 – Goodchap St, Noosa 9
3.3.3.2 Treatment Nodes
The following devices have been used in the treatment train to reduce these pollutant loads to achieve WQO’s.
Stormwater Harvesting – A 200kL volume of stormwater harvesting has been included in the
model. The re-use has been modelled for both irrigation (777kL/year) and toilet/laundry use (7.2kL
per day) as per the MUSIC modelling guidelines Section 4.2 for the site area and a 90 bed facility;
SPEL ‘SPELFilter’ Cartridges – Standard underground cartridges were required to achieve the
WQO’s. The filters use an upflow treatment process, through a spiral wrapped media configuration
that maximises surface treatment area. Refer to Appendix D for specifications. The design
proposed is:
o 4 Cartridges;
SPE ‘StormSacks’ GPT – A number of baskets installed to the top of field inlets to trap coarse
sediment prior to entering the drainage system was modelled in line with the cartridge system. The
design proposed is:
o 3 Baskets;
3.3.4 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 3.6 indicates the predicted pollutant mean values of stormwater
discharged as calculated by MUSIC:
Pollutant Percentage Load Reduction
Total Suspended Solids (TSS) 84.0%
Total Phosphorus (TP) 67.3%
Total Nitrogen (TN) 60.6%
Gross Pollutants (>5mm) 100%
Table 3.6 - 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.
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SC7440 – Goodchap St, Noosa 10 4.0 Stormwater Quantity Management 4.1 Background The proposed development has the potential to alter the existing hydrologic and hydraulic characteristics of the subject site unless suitable mitigation is achieved via careful hydraulic design of the proposed stormwater management drainage system. With urbanisation there is potential for sites 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 mitigated and conveyed from the site in a manner that complies with Council’s Urban 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. 4.2 Site Drainage Constraints and Opportunities 4.2.1 Drainage Constraints The increase of impervious areas will impact on the existing downstream boundary condition compared to pre-development peak flows. Therefore, a volume of detention will be required to limit flows to that of pre- development. 4.2.2 Drainage Opportunities The existing drainage in Val Crescent provides sufficient depth for connection to provide quality and quantity objectives. 4.3 Modelling Overview 4.3.1 Methodology The software package XP-STORM V2017.2, has been used to model the site in its current and post- developed state. The modelling has been undertaken to determine detail design parameters of on-site detention to replicate pre-development peak flow rates. As the development falls within the ‘Urban Residential’ development category (QUDM), the minor (10yr ARI) and major (100yr ARI) storm events were primarily sized for underground and overland design flows respectively. All events ranging from 2, 5, 10 20, 50 and up to the 100yr were analysed to compare pre/post development discharges ensuring ‘non-worsening’ discharge. The development modelling and analysis undertaken was based on the information provided by the detailed site survey and preliminary architectural layouts. A Rational Method “check” was conducted and compared with the pre-development model to confirm there were no gross errors, refer to Appendix E for Rational Method results.
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SC7440 – Goodchap St, Noosa 11
4.3.2 Catchment Areas
The subject site has been modelled in its existing pre-development and proposed post-development states
with the catchment areas illustrated in Tables 4.1 & 4.2. In its pre-development state the subject site was
modelled as one hydrologic node to replicate the existing drainage situation for the lot. XP-STORM model
layouts and outputs are included in Appendix C of this report.
Node Description % Impervious Area (Ha)
Landscape 0 0.512
‘PRE’
Roof 100 0.162
Total Catchment (ha) 24 0.674
Table 4.1 - Pre Development Node Sub-Catchment Areas
Node Description % Impervious Area (Ha)
‘TANK’ Roof 100 0.400
Carpark/hardstand areas 100 0.085
Landscape 0 0.189
Total Catchment (ha) 72 0.674
Table 4.2 - Post Development Sub–Catchment Areas
4.3.3 Roughness Coefficients
The conduits and links used within the model are based on the ultimate design scenario for the internal
roadways and overland flow paths. Mannings “n” roughness coefficient values are specified as 0.014 for
RCP pipes and 0.011 for uPVC pipes.
For overland flow within the sub-catchment areas a Mannings “n” value of 0.014 for concrete areas and
0.045 for vegetated areas was adopted.
4.3.4 Storm Events
Storm patterns were setup using Australian Rainfall and Runoff (ARR 1987) storm patterns for Area 3 with
intensity frequency duration data taken for the local area. Storm durations of 10, 15, 20, 25, 30, 45, 60 and
90 minutes were investigated for the pre and post developed scenarios.
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SC7440 – Goodchap St, Noosa 12
4.3.5 Outlet Condition
The subject site is not impacted by regional flooding, refer Section 5.0. The Val Crescent gully inlets have
been modelled with an assumed upstream catchment to estimate the HGL rise through the different storm
events.
4.3.6 On-Site Detention
It is calculated from the development site plan that the proposed development will increase impervious
areas on the site from 24% to 72%. The proposed increase in impervious areas has the potential to
increase peak flow rates to the existing drainage system. To mitigate potential increases in flow rates it is
planned to detain stormwater flows on-site and discharge at a mitigated rate to the existing swale.
Mitigation of flow is provided by the following volume:
Approximately 225kL of total detention volume within an underground tank. Flows from this storage
volume will be throttled by a reduced cross-sectional area connection at the outlet (2/225mm), and
high level overflow pipes. Refer to Figure 4.1 for the detention tank details modelled.
Figure 4.1 – Detention Tank Parameters
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SC7440 – Goodchap St, Noosa 13
Flows from minor storms up to and including the 10 year ARI are to be conveyed in the underground
drainage system. Major storm events exceeding the ARI10 year, up to and including the peak ARI 100 year
events will overtop the stormwater pits fronting the boundary and flow overland into Council’s road reserve.
A concept drainage layout plan has been included as Appendix A of this report.
4.4 Modelling Results
A node layout plan is included in Appendix C of this report and the resultant peak flow rates are displayed
in Table 4.3 & 4.4.
ARI Design Storm (min) Peak Flow (m3/s)
2 60 0.170
5 60 0.230
10 60 0.262
20 60 0.309
50 60 0.350
100 60 0.392
Table 4.3 – Pre-Development Peak Flow Rate Results
ARI Design Storm (min) Peak Flow (m3/s)
2 60 0.104
5 60 0.124
10 60 0.133
20 60 0.197
50 60 0.254
100 60 0.285
Table 4.4 – Post-Development (mitigated) Peak Flow Rate Results
As can be seen in Tables 4.3 & 4.4 the post-development peak flow rates to the existing drainage system
compare well to that of the existing pre-development site discharges. This is due to the large volumes of
on-site detention proposed to be included as part of the development.
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SC7440 – Goodchap St, Noosa 14
4.5 Impacts on Existing Infrastructure
Due to the existing nature of the site an assessment of the proposed development and its impact on the
existing infrastructure was conducted. This is to ensure non-worsening impacts on the downstream
boundary condition further than the point of connection. Council’s infrastructure was identified from detailed
site survey and mapping services, refer to Figure 4.2.
Figure 4.2 – External Stormwater Network
Approximate catchments were identified for each node as illustrated in Figure 4.3 & 4.4.
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SC7440 – Goodchap St, Noosa 15
UNDERGROUND DRAINAGE
OVERLAND FLOW
Figure 4.3 - Pre-Development Catchment Plan
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SC7440 – Goodchap St, Noosa 16
UNDERGROUND DRAINAGE
OVERLAND FLOW
Figure 4.4 - Post-Development Catchment Plan
Storm events of 2, 10, and 100 year with 60 minute durations were analysed to ensure no worsening
impacts on the critical nodes. Tables 4.5-4.7 illustrate the pre-development and post-development HGL
and downstream flow rate results to each external node.
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SC7440 – Goodchap St, Noosa 17
Node Pre-Development Post-Development
HGL (m) Downstream U/G Hydraulic Grade Downstream Flow
3
Flow Rate (m /s) Line (HGL) (m) Rate (m3/s)
A.2 2.848 0.186 2.841 0.177
A.3.1 3.199 0.050 3.043 0.034
A.5 3.366 0.068 3.189 0.064
A.1 2.644 0.186 2.628 0.177
Table 4.5 – Pre vs. Post-Development External Network Results (2yr Event)
Node Pre-Development Post-Development
HGL (m) Downstream U/G Hydraulic Grade Downstream Flow
3
Flow Rate (m /s) Line (HGL) (m) Rate (m3/s)
A.2 3.097 0.248 3.035 0.224
A.3.1 3.512 (S) 0.062 3.325 0.045
A.5 3.766 (S) 0.084 3.470 0.069
A.1 2.783 0.248 2.726 0.224
Table 4.5 – Pre vs. Post-Development External Network Results (10yr Event)
*Note: (S) denotes a surcharging node
Node Pre-Development Post-Development
HGL (m) Downstream U/G Hydraulic Grade Downstream Flow
3
Flow Rate (m /s) Line (HGL) (m) Rate (m3/s)
A.2 3.153 0.257 3.172 0.254
A.3.1 3.549 (S) 0.062 3.527 (S) 0.050
A.5 3.795 (S) 0.084 3.794 (S) 0.082
A.1 2.816 0.257 2.804 0.255
Table 4.5 – Pre vs. Post-Development External Network Results (100yr Event)
*Note: (S) denotes a surcharging node
The results demonstrate that the proposed on-site detention volume generally provided at least equal or
reduced HGL levels and flow rates compared to the pre-development scenario. Furthermore, it was found
that the surcharging gully inlets in the pre-development 10 year event do not surcharge in the post-
development design due to the reduction in flow. The proposed stormwater management plan therefore
satisfies both Council and QUDM requirements for non-worsening discharge.
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SC7440 – Goodchap St, Noosa 18
5.0 Flood Hazard Overlay
The subject site is not flood affected as per Council’s major event regional flood hazard mapping, refer
Figure 5.1.
Subject Site
Figure 5.1 – Flood Hazard Overlay Mapping (Noosa Council)
Figure 5.1 also illustrates that Val Crescent and Good Chap Street are not flood affected within proximity to
the site, allowing safe access/egress at all cross-over locations.
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SC7440 – Goodchap St, Noosa 19
6.0 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 includes a
SPEL Environmental system of four (4) STORMFILTER cartridges, three (3) STORMSACK
baskets, and 200kL of stormwater harvesting;
A combined 225kL of detention volume is proposed to mitigate peak flows to that of the pre-
development scenario to ensure a situation of ‘non-worsening’;
The flood hazard overlay mapping does not impact on the subject site or prevent access/egress to
the site.
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APPENDIX A – STORMWATER MANAGEMENT PLAN
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APPENDIX A — STORMWATER MANAGEMENT PLAN
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LEGEND
H
4.01
H
CONCEPT STORMWATER MANAGEMENT PLAN
Bundaberg Gladstone Sunshine Coast
9 Princess Street Bundaberg Qld 4 Goondoon Street Gladstone Qld 45 Brisbane Road Mooloolaba Qld
PO Box 2052 Bundaberg Qld 4670 PO Box 1743 Gladstone DC Qld 4680 PO Box 102 Mooloolaba Qld 4557
T: 07 4154 4894 F: 07 4154 4274 T: 07 4972 5387 T: 07 5477 6437 F: 07 5444 4216
E: [email protected] E: [email protected] E: [email protected]
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SC7440 – Goodchap St, Noosa 21 APPENDIX B – STORMWATER QUALITY MUSIC MODELLING [OCR of page images] $C7440 — Goodchap St, Noosa 21 APPENDIX B —- STORMWATER QUALITY MUSIC MODELLING
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SC7440 – Goodchap St, Noosa 22
Figure B.1 – MUSIC Model Node Layout
Figure B.2 – MUSIC Model Treatment Train Effectiveness
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Figure B.3 – MUSIC Model ‘SPEL Filter’ Node
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Inlet Pro
Low Flow By-pass (cubic metres per sec)
High Flow By-pass (cubic metres per sec)
> Target Element
(@ Flow (cubic metres per sec)
© Gross Pollutants (kg/ML)
© Total Suspended Solids (mg/L)
© Total Phosporus (mg/L)
© Total Nitrogen (mg/L)
;-Flow (cubic metres per sec)
| Transfer Functions:
Cc tration Based Capture Efficiency
© Flow Based Capture Efficiency
Flow Based Capture Efficiency
Sal o=| ala
Figure B.3 — MUSIC Model ‘SPEL Filter’ Node
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SC7440 – Goodchap St, Noosa 24
Figure B.4 – MUSIC Model Rainfall Data
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SC7440 — Goodchap St, Noosa 24
Catchment Name [5C7440-GoodChap St
Rainfall Station [40059COOROY
ET Station [User-defined monthly PET
Start Date fvovs7300:00 0 =¢«€@2~C~C~*
End Date fiizi93 23:54 —~C*~*
Modeling Time Step [6Minutes
Ba| S| |
Milimetres
il ci
I Wi
1212973 12121974 «1221975 14976 «—ANZM977 ~—«11/12/1978 11/12/1979 10/12/1980 10/12/1981 10/12/1982 10/12/1983
— Rainfall — Evapo-transpiration|
Left click and drag to zoom the graph - right click and drag to scroll.
Figure B.4 — MUSIC Model Rainfall Data
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APPENDIX C – XP-STORM MODELLING
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APPENDIX C — XP-STORM MODELLING
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Site Location: Noosa
DURATION 1 Year 2 years 5 years 10 years 20 years 50 years 100 years
5Mins 130.00 165.00 202.00 224.00 253.00 291.00 320.00
6Mins 122.00 155.00 190.00 210.00 238.00 274.00 302.00
10Mins 100.00 127.00 156.00 173.00 197.00 227.00 250.00
20Mins 73.70 93.50 116.00 128.00 145.00 168.00 185.00
30Mins 60.20 76.50 94.70 105.00 119.00 138.00 152.00
1Hr 40.60 51.90 64.90 72.40 82.60 96.10 106.00
2Hrs 26.00 33.40 42.60 48.10 55.40 65.10 72.60
3Hrs 19.60 25.40 33.00 37.50 43.50 51.50 57.70
6Hrs 12.10 15.80 21.10 24.40 28.70 34.40 39.00
12Hrs 7.65 10.10 13.80 16.20 19.20 23.30 26.60
24Hrs 5.04 6.69 9.30 11.00 13.10 16.10 18.50
48Hrs 3.35 4.47 6.28 7.45 8.96 11.00 12.70
72Hrs 2.53 3.39 4.81 5.75 6.94 8.60 9.94
Table C.1 - IFD Date Sourced from BOM
ARI in 1 2 5 10 20 50 100
years
coefficient 3.68E+00 3.92E+00 4.15E+00 4.27E+00 4.4039206 4.56E+00 4.67E+00
A
51
coefficient -5.98E-01 -5.90E-01 -5.67E-01 -5.55E-01 -5.45E-01 -5.33E-01 -5.25E-01
B
coefficient -4.98E-02 -4.54E-02 -3.46E-02 -2.84E-02 -2.35E-02 -1.80E-02 -1.40E-02
C
coefficient 6.89E-03 6.75E-03 6.57E-03 6.45E-03 6.23E-03 6.05E-03 0.01
D
coefficient 2.68E-03 2.25E-03 1.30E-03 7.23E-04 2.98E-04 -1.75E-04 -5.34E-04
E
coefficient -9.82E-05 -8.61E-05 -7.75E-05 -6.28E-05 -4.09E-05 -2.28E-05 -3.69E-06
F
coefficient -9.36E-05 -8.24E-05 -5.73E-05 -4.33E-05 -3.49E-05 -2.46E-05 -1.74E-05
G
Table C.2 – Coefficients (BOM)
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Site Location: Noosa
DURATION 1 Year | 2 years 5 years 10 years | 20 years | 50 years 100 years
5Mins 130.00 | 165.00 202.00 224.00 253.00 291.00 320.00
6Mins 122.00 | 155.00 190.00 210.00 238.00 274.00 302.00
10Mins 100.00 | 127.00 156.00 173.00 197.00 227.00 250.00
20Mins 73.70 | 93.50 116.00 128.00 145.00 168.00 185.00
30Mins 60.20 | 76.50 94.70 105.00 119.00 138.00 152.00
1Hr 40.60 | 51.90 64.90 72.40 82.60 96.10 106.00
2Hrs 26.00 33.40 42.60 48.10 55.40 65.10 72.60
3Hrs 19.60 | 25.40 33.00 37.50 43.50 51.50 57.70
6Hrs 12.10 15.80 21.10 24.40 28.70 34.40 39.00
12Hrs 7.65 10.10 13.80 16.20 19.20 23.30 26.60
24Hrs 5.04 6.69 9.30 11.00 13.10 16.10 18.50
48Hrs 3.35 4.47 6.28 7.45 8.96 11.00 12.70
72Hrs 2.53 3.39 4.81 5.75 6.94 8.60 9.94
Table C.1 - IFD Date Sourced from BOM
ARI in 1 2 5 10 20 50 100
years
coefficient 3.68E+00 | 3.92E+00 | 4.15E+00 | 4.27E+00 | 4.4039206 | 4.56E+00 | 4.67E+00
A 51
coefficient | -5.98E-01 | -5.90E-01 | -5.67E-01 | -5.55E-01 | -5.45E-01 | -5.33E-01 | -5.25E-01
B
cefficient -4.98E-02 | -4.54E-02 | -3.46E-02 | -2.84E-02 | -2.35E-02 | -1.80E-02 | -1.40E-02
coefficient 6.89E-03 | 6.75E-03 | 6.57E-03 | 6.45E-03 | 6.23E-03 | 6.05E-03 | 0.01
coefficient 2.68E-03 2.25E-03 1.30E-03 7.23E-04 2.98E-04 -1.75E-04 | -5.34E-04
E
coefficient | -9.82E-05 | -8.61E-05 | -7.75E-05 | -6.28E-05 | -4.09E-05 | -2.28E-05 | -3.69E-06
F
coefficient -9.36E-05 | -8.24E-05 | -5.73E-05 | -4.33E-05 | -3.49E-05 | -2.46E-05 | -1.74E-05
Table C.2 — Coefficients (BOM)
Page 29
SC7440 – Goodchap St, Noosa 27
Figure C.1 – XP Storm Pre-Development Catchment Plan
Figure C.2 – Pre-developed Peak Flow Hydrograph (SUBJECT SITE ONLY)
Page 30
SC7440 – Goodchap St, Noosa 28
Figure C.3 – XP Storm Post-Development Catchment Plan
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C7440 - Goodchap St, Noosa 28
i uf Piped
Figure C.3 — XP Storm Post-Development Catchment Plan
Page 31
SC7440 – Goodchap St, Noosa 29
Figure C.4 – Post-developed Peak Flow Hydrograph
[OCR of page images]
$C7440 — Goodchap St, Noosa
29
Flow
Flow
—=
2 15minMax 0.088}
=
25 15mingliax 0.106)
10 15minfMax 0.114]
220 15minfMax 0.124]
=
50 *5minjMax 0.129]
0.15
0.10
0.05
0.00
Sun 1
Jan 1995
=
22 15min|Mex 0.000),
=
(Q5 15min(Max 0.000)
—=
210 15minjtitax 0.000)
=
(2100 15minfMax 0.031)
—=
2 2omin|Max 0.099],
=
(05 2omin|Max 0.110)
=
(210 2ominfMex 0.116]
220 20min(Max 0.126]
50 20min{Max 0.137]
(2100 20minjbtax 0.140]
Conduit 1.4 lo from TANK out to 1.3
=
2 25min[Pex 0.102]
(05 26min 0.113]
(010 25minfMax 0.120)
(020 a5minitix 0.132)
{80 25manftek 0.144}
100 25minMex 0.142]
=
2 30minfMax 0.100]
=
25 30minfMax 0.112}
210 30min{Max 0.123]
220 30min{Max 0.195]
50 30minjMax 0.142]
2100 3ominftax 0.143]
=
(seme 0.0971
Q5 45min[Max 0.116)
0 amines 0127]
20 a5miniNax 0.139)
150 45min 0444)
=
(2100 45minjbtax 0.144]
=
2 Gomin[Pax 0.104]
5 Gomin|bex 0.124)
}
210 6ominfhfax 0.133),
220 Gominfhax 0.141),
!
250 Gominfhax 0.141)
100 ominytax 0.142)
=
(22 90mintax 0.102)
5 ore 0120)
210 90min 0.130)
220 S0miniiax 0140)
50 gominfvax 0.439]
(2100 somingiiax 0.139]
=
2 120minjhtex 0.098]
06 120minfMex 0.118]
=
(Q10 120minfbax 0.128]
=
(220 120minfbtax 0.138]
(250 120minjbax 0.139]
100 120min|Max 0.139),
=
22 20min|Max 0.000),
=
(Q5 20min(Max 0.000},
210 20min{hitax 0.000),
(220 2omin{iiax 0.000),
(250 2ominfhitax 0.026),
2100 2omintax 0.080}
0:30
=
(2 25min|Max 0.000),
(Q5 25min(Max 0.000},
=
210 25minfhifax 0.000),
(220 26min{hiex 0.000),
(250 25minfhiax 0.047),
2100 25minfMax 0.087)
1:00
Time
Figure C.4 — Post-developed Peak Flow Hydrograph
Conduit 1.4 hi from TANK out to 1.3
=
22 30min|Max 0.000),
(Q5 30min(Max 0.000),
=
(210 Sominfitax 0.000),
(220 3omin{hilex 0.000),
(250 S0minfhiiax 0.061),
=
2100 3ominfMax 0.104]
=
2 45min|Max 0.000),
(Q5 45min(Max 0.000),
=
210 45minfhifax 0.000),
(220 4bmin{iiax 0.013),
(250 4siminfitax 0.091),
2100 45minfMiax 0.127]
=
2 60min{Max 0.000),
Q5 60min(Max 0.000},
(210 Gominjhitax 0.000),
=
(220 Bominfhfex 0.056)
(250 Gominftiiax 0.113),
=
100 eominfifax 0.143]
=
22 90min|Mex 0.000),
25 90min(Max 0.000),
10 90minfax 0.000}
=
(220 90minfiax 0.038)
(050 90minfax 0.104]
2100 SominfMax 0.145
=
(22 120minfiax 0.000}
=
05 120minfMtax 0.000]
210 120minjutax 0.000}
=
220 120minjMiax 0.029}
(2100 1 20enin|Max 0.133]
Sun1
Jan 1995
1:30
2:00
Page 32
SC7440 – Goodchap St, Noosa 30
APPENDIX D – SPEL SPECIFICATIONS
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$C7440 — Goodchap St, Noosa
30
APPENDIX D — SPEL SPECIFICATIONS
Page 33
SPELFilter
Cartridge Filter For Tertiary Stormwater Treatment
www.spel.com.au
[OCR of page images]
SPELFilter
Cartridge Filter For Tertiary Stormwater Treatment
www.spel.com.au
INTEGRATED WATER SOLUTIONS
Page 34
Where intuitive
technology meets value.
SPEL Applications Engineers are ready
to design a custom SPELFilter system
to meet the demands of your site.
SPELFilter provides the performance of
a biofiltration system without the surface
footprint disadvantage of vegetated
assets. SPELFilter maximises your land
use on constrained sites.
Features
» Achieves 80% TSS Removal How it works
» Achieves 60% TP Removal The SPELFilter has an upflow treatment process,
through a spiral wrapped media configuration that
maximises surface area. The benefit is excellent pollutant
» Achieves 45% TN Removal removal in a small footprint.
» Achieves 60% reduction in Hydraulic pressure forces water through the filter media,
discharges through the centre tube and out through the
Copper concentrations outlet collection manifold.
» Achieves 40% reduction in Upon completion of a treatment cycle, each cartridge
backwashes and effectively dislodges particulates from
Zinc concentrations the filtration layers. This reestablishes filter porosity. The
dislodged particles accumulate on the vault floor for
easy removal during maintenance.
SPELFilter’s patented design has no moving parts and
generates a true siphon effect.
A SPEL Stormceptor Class 1 upstream of the SPELFilter
in the treatment train greatly increases the life cycle
interval of the SPELFilter as the SPEL Stormceptor
Class1 removes the larger gross pollutants, coarse
sediments, total suspended solids and hydrocarbons,
enabling the SPELFilter to target fine particulate matter
and nutrients.
2
Page 35
Value & Benefits Filter Configurations
Proven Sand Filter Performance:
The uniform size silica-sand filter media provides
for higher removal efficiencies than coarser types
of media. SPELFilter media is inorganic – it doesn’t
leach nitrogen and other nutrients.
Greater flexibility:
Due to the significant surface area, designated
flow path and high flow capacity, combined with
the modular cartridge design, the SPELFilter
system can be deployed in a variety of structures
including manholes, precast vaults, or cast-in-place
structures.
Each system is optimised to suit your specific site
and local authority requirements by qualified and
experienced professionals.
Spiral Cross-Section Spiral Design
3
Page 36
SPEL Stormsack
At-source Gross Pollutant Trap
www.spel.com.au
[OCR of page images]
EL Stormsack
At-source Gross Pollutant Trap
www.spel.com.au
INTEGRATED WATER SOLUTIONS
Page 37
Stormwater
Treatment
An all too common issue with today’s highly impervious
landscape is how to meet stormwater regulations with
limited budgets and tight space constraints.
SPEL StormSack filtration solutions are highly engineered
water quality devices that are deployed directly in the
stormwater system to capture contaminants close the
surface for ease of maintenance. Easily retrofitted into new
or existing structures, SPEL StormSack filtration technology
is a decentralized approach to stormwater treatment that
essentially repurposes traditional site infrastructure and
customizes it to meet specific site water quality goals. In
this way, it satisfies important objectives of today’s LID
(Low Impact Development) criteria.
From an operations perspective, catch basins with SPEL
Stormsack filters are also easier and quicker to clean out
because pollutants are trapped just under the grate.
StormSack
The SPEL StormSack is specifically designed for the
capture of gross pollutants: sediment, litter, and oil and
grease. Ideally suited for municipal storm drain retrofits,
the SPEL StormSack’s unique design allows maintenance
to be performed using conventional vacuum suction
equipment.
Application Regulatory Issue Target Pollutants
Council Storm Drain Retrofits At-source litter capture Sediment, Litter, O&G
Commercial/Retail/Residential Stormwater Compliance Sediment, Litter, O&G
Litter Prone Urban Areas Cost effective litter control Litter ≥ 5 mm
Scrap Metal/Solid Waste/Oil Storage/Etc Industrial Multi-Sector General Permit Gross Pollutants, O&G
Part of Treatment Train Council Stormwater Quality Improvement Targets Sediment, Litter, O&G
Construction Sediment/Erosion Sediment Control Plan Sediment/Erosion Control
[ 1] [6] [ 5]
Features Standard SPEL
Stormsack to suit
1. Durable, aluminum frame construction [2] Pit Sizes
Integral oil boom effectively captures 450x450mm
2. [3]
oil and grease from spills
600x600mm
Patented dovetailed flange – allows
3.
12cm of length/width field adjustment
[4] 900x600mm
900x900mm
Polypropylene netting protects sack
4.
from suction hose during maintenance
Steel clip with locking tab holds Custom sizes (i.e.
5. 1200x900mm) can
replaceable filter sack in place
6. Baffled bypass traps floatables
be manufactured on
short lead times
2
Page 38
Specifications & Details
General Description
This technology is a post developed stormwater treatment
system. The SPEL StormSack provides effective filtration
of solid pollutants and debris typical of urban runoff, while
utilising the existing or new storm drain infrastructure.
The StormSack is designed to rest on the flanges of
conventional catch basin frames and is engineered for
most hydraulic and cold climate conditions.
Installation And Maintenance
Installation procedures shall include removing the storm
grate, cleaning the ledge of debris and solids, measuring
catch basin clear opening and adjusting flanges to rest on
grate support ledge. Install SPEL StormSack with splash
guard under curb opening so the adjustable flanges are
resting on the grate support ledge. Install corner filler
pieces. Reinstall storm grate directly on support flanges
[rise shall be no more than 1/8 inch (3 mm)].
Maintenance: Typically the SPEL StormSack is serviceable
from the street level, and therefore maintenance does not
require confined space entry into the catch basin structure.
The unit is designed to be maintained in place with a
vacuum hose attached to a sweeper or a vactor truck. The
oil boom is also designed to easily be replaced from the
street level. Use only SPEL replaceable parts.
Products
Material and Design
A. Adjustable Flange and Deflector: Aluminum Alloy
6063-T6
B. Splash Guard: neoprene rubber
Benefits
C. Stormsack: woven polypropylene geotextile with US
Mesh 20 t-PXDPTUHSPTTQPMMVUBOUDBQUVSF
D. Corner Filler: Aluminum Allow 5052-H32 t2VJDLFBTZJOTUBMMBUJPO
E. Lifting Tabs: Aluminum Allow 5052-H32
t4JNQMFNBJOUFOBODF
F. Replaceable Oil Boom: polypropylene 3 inch
(76 mm) diameter t"UTPVSDFDBQUVSF
G. Mesh Liner: HDPE, diamond configuration t"EKVTUTUPDVTUPNQJUTJ[FT
H. Support Hardware: CRES 300 Series
Typical Performance Characteristics Field Performance
A. Debris capacity: 8.5cu. ft. (0.24 m3) The SPEL Stormsack was introduced to the Australian
B. Filtered flow rate: 7.3 cfs (207 lps) market in 2012 and field testing is underway at several
C. Primary baffled bypass flow rate: 4.2cfs (119 lps) locations in South-east Queensland. Laboratory testing
D. Secondary bypass flow rate: 0.4 cfs (10 lps) has shown capture of 99.99% of gross pollutants up to the
bypass flow rate.* Further results will be provided as they
E. Total bypass flow rate: 4.6 cfs (130 lps)
become available.
F. Oil boom sorption capacity: 376 oz (11 L)
Recommended minimum clearance from bottom of SPEL
StormSack to inside bottom of vault is 2 inches (50 mm)
Typical frame adjustability range of 5 inches (127 mm) in
each direction.
3
[OCR of page images]
Specifications & Details
General Description
This technology is a post developed stormwater treatment
system. The SPEL StormSack provides effective filtration
of solid pollutants and debris typical of urban runoff, while
utilising the existing or new storm drain infrastructure.
The StormSack is designed to rest on the flanges of
conventional catch basin frames and is engineered for
most hydraulic and cold climate conditions.
Installation And Maintenance
Installation procedures shall include removing the storm
grate, cleaning the ledge of debris and solids, measuring
catch basin clear opening and adjusting flanges to rest on
grate support ledge. Install SPEL StormSack with splash
guard under curb opening so the adjustable flanges are
resting on the grate support ledge. Install corner filler
pieces. Reinstall storm grate directly on support flanges
{rise shall be no more than 1/8 inch (3 mm)].
Maintenance: Typically the SPEL StormSack is serviceable
from the street level, and therefore maintenance does not
require confined space entry into the catch basin structure.
The unit is designed to be maintained in place with a
vacuum hose attached to a sweeper or a vactor truck. The
oil boom is also designed to easily be replaced from the
street level. Use only SPEL replaceable parts.
Products
Material and Design
A. Adjustable Flange and Deflector: Aluminum Alloy
6063-T6
B. Splash Guard: neoprene rubber
C. Stormsack: woven polypropylene geotextile with US
Mesh 20
D. Corner Filler: Aluminum Allow 5052-H32
E. Lifting Tabs: Aluminum Allow 5052-H32
F. Replaceable Oil Boom: polypropylene 3 inch
(76 mm) diameter
G. Mesh Liner: HDPE, diamond configuration
H. Support Hardware: CRES 300 Series
Typical Performance Characteristics
A. Debris capacity: 8.5cu. ft. (0.24 m3)
B. Filtered flow rate: 7.3 cfs (207 Ips)
C. Primary baffled bypass flow rate: 4.2cfs (119 lps)
D. Secondary bypass flow rate: 0.4 cfs (10 lps)
E. Total bypass flow rate: 4.6 cfs (130 lps)
F. Oil boom sorption capacity: 376 oz (11 L)
Recommended minimum clearance from bottom of SPEL
StormSack to inside bottom of vault is 2 inches (60 mm)
Typical frame adjustability range of 5 inches (127 mm) in
each direction.
Benefits
e Low cost gross pollutant capture
© Quick & easy installation
¢ Simple maintenance
e At source capture
e Adjusts to custom pit sizes
Field Performance
The SPEL Stormsack was introduced to the Australian
market in 2012 and field testing is underway at several
locations in South-east Queensland. Laboratory testing
has shown capture of 99.99% of gross pollutants up to the
bypass flow rate.* Further results will be provided as they
become available.
Page 39
HEAD OFFICE
PO Box 6144
Silverwater NSW 1811
100 Silverwater Rd
Silverwater NSW 2128
Phone: +61 2 8705 0255
Fax: +61 2 8014 8699
DESIGN OFFICES
New South Wales 61 2 8705 0255
Canberra 61 2 6128 1000
Queensland 61 7 3271 6960
Victoria & Tasmania 61 3 5274 1336
South Australia 61 8 8275 8000
West Australia 61 8 9350 1000
Northern Territory 61 2 8705 0255
New Zealand 64 9 276 9045
www.spel.com.au
SPEL Environmental accepts no responsibility for any loss or damage resulting
from any person acting on this information. The details and dimensions contained
in this document may change, please check with SPEL Environmental for
confirmation of current specifications.
0033 SPEL StormSack 2.0
Page 40
HEAD OFFICE
PO Box 6144
Silverwater NSW 1811
100 Silverwater Rd
Silverwater NSW 2128
Phone: +61 2 8705 0255
Fax: +61 2 8014 8699
DESIGN OFFICES
New South Wales 61 2 8705 0255
Canberra 61 2 6128 1000
Queensland 61 7 3271 6960
Victoria & Tasmania 61 3 5274 1336
South Australia 61 8 8275 8000
West Australia 61 8 9350 1000
Northern Territory 61 2 8705 0255
New Zealand 64 9 276 9045
www.spel.com.au
SPEL Environmental accepts no responsibility for any loss or damage resulting
from any person acting on this information. The details and dimensions contained
in this document may change, please check with SPEL Environmental for
confirmation of current specifications.
0033.5 SPELFilter 2.0
Page 41
SC7440 – Goodchap St, Noosa 31
APPENDIX E – RATIONAL METHOD CALCULATIONS
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$C7440 — Goodchap St, Noosa
31
APPENDIX E — RATIONAL METHOD CALCULATIONS
Page 42
Rational Method Analysis
Site Location:
Noosa
Q = CIA/360 IFD data from BOM
Where: DURATION 1 Year 2 years 5 years 10 years 20 years 50 years 100 years
Q = Flow rate (m3/s) 5Mins 130.00 165.00 202.00 224.00 253.00 291.00 320.00
C = Coefficient of discharge 6Mins 122.00 155.00 190.00 210.00 238.00 274.00 302.00
I = average rainfall intensity (mm/hr) 10Mins 100.00 127.00 156.00 173.00 197.00 227.00 250.00
A = area of catchment (ha) 20Mins 73.70 93.50 116.00 128.00 145.00 168.00 185.00
30Mins 60.20 76.50 94.70 105.00 119.00 138.00 152.00
I = Requires time of concentration (Tc) 1Hr 40.60 51.90 64.90 72.40 82.60 96.10 106.00
Tc calculated by Friends Equation 2Hrs 26.00 33.40 42.60 48.10 55.40 65.10 72.60
3Hrs 19.60 25.40 33.00 37.50 43.50 51.50 57.70
Friends Equation: Tc = (107nL0.333)/S0.2 6Hrs 12.10 15.80 21.10 24.40 28.70 34.40 39.00
Where: 12Hrs 7.65 10.10 13.80 16.20 19.20 23.30 26.60
n = Hortons surface roughness factor 24Hrs 5.04 6.69 9.30 11.00 13.10 16.10 18.50
L = overland sheet flow path length 48Hrs 3.35 4.47 6.28 7.45 8.96 11.00 12.70
S = slope of surface (%) 72Hrs 2.53 3.39 4.81 5.75 6.94 8.60 9.94
Existing Existing
Tc (mins) 9 n 0.035
L 35
Therefore intensities (I) using Tc are as follows: S 5
Tc = (mins) 8.9
ARI Existing
1 101.28
2 129.00
5 160.14
10 178.18
20 203.03
50 235.62
100 260.59
1 hour 10 year intensity (1I10)=
72.40
1
I10 used with Fraction impervious (Fi) to determine C10 then multiplied by Frequency factor (Fy)
Existing
Area (ha) 0.674 **Note: C10 value derived for existing conditions as Intenisty, Area, and Flow were known values
Fi 24
C10 0.76 ARI Frequency factor (Fy)
C1 0.608 1 0.8
C2 0.646 2 0.85
C5 0.722 5 0.95
C10 0.760 10 1
C20 0.798 20 1.05
C50 0.874 50 1.15
C100 0.912 100 1.2
Flow rates can then be calculated by Q = CIA/360:
Q (m3/s)
ARI Existing
1 0.115
2 0.156
5 0.216
10 0.254
20 0.303
50 0.386
100 0.445
Used in these records
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