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Att 2 SWMP
Attachment 2 Stormwater Management Plan Response to Council’s Information Request– Application for a Development Permit to Establish Caretakers accommodation, Outdoor Sales and Low Impact Industry MCU21/0104 Address: 16 Rene St, Noosaville Lot 13 on RP150347 Scooter Style Pty Ltd Ronald and Margaret Salmon
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Scooter Style, 16 Rene St 20210121 RG Strategic Preliminary Stormwater Management Plan October 2021
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Document control record
Document prepared by:
RECOR Pty Ltd
ABN 89 647 469 707
37 Mary Street
Noosaville, QLD 4566
Australia
T +61 7 5211 1003
E [email protected]
W recorconsulting.com
A person using RECOR documents or data accepts the risk of:
a) Using the documents or data in electronic form without requesting and checking them for accuracy against the original hard
copy version.
b) Using the documents or data for any purpose not agreed to in writing by RECOR.
Document control
Report title Preliminary Stormwater Management Plan
Document code 20210121-SWMP01 Project number 20210121
File path Https://recorconsulting.sharepoint.com/sites/BusinessDevelopment/Shared
Documents/General/Templates/Report Template.docx
Client RG Strategic
Client contact - Client reference -
Rev Date Revision details/status Author Reviewer Verifier Approver
(if required)
0 07/10/2021 Initial Version B. Parry M. Poynter
Current revision 0
Approval
Author signature Approver signature
Name B. Parry Name
Title Civil Engineer Title
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A 37 Mary St, Noosaville Qld 4566 E [email protected]
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Contents
Introduction..........................................................................................................................................4
Site Details ...........................................................................................................................................5
2.1. Existing Site Description ...................................................................................................................... 5
2.2. Existing Drainage Patterns .................................................................................................................. 5
2.3. Proposed Development Drainage Pattern ......................................................................................... 6
2.4. Flood Considerations ........................................................................................................................... 7
2.5. Acid Sulphate Soils .............................................................................................................................. 7
Stormwater Quantity ............................................................................................................................9
3.1. Pre-Post Comparison .......................................................................................................................... 9
Stormwater Quality ........................................................................................................................... 13
4.1. Construction Phase ........................................................................................................................... 13
4.2. Operational Phase ............................................................................................................................ 14
Conclusion ........................................................................................................................................ 20
Appendices
Appendix A
Proposed Stormwater Layout Plan
Appendix B
WBNM Modelling Parameters
Appendix C
Bioretention Inspection Checklist
Appendix D
Noosa Council Works Code Checklist
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INTRODUCTION RECOR has been commissioned to prepare a preliminary Stormwater Management Report to accompany a development application for a caretaker building and an additional carparking area within an existing industrial lot. This report examines the stormwater management considerations for the existing and proposed development site and assesses how the run-off from the site is to be managed in accordance with Noosa Shire Council requirements for stormwater drainage. Project number 20210121 File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 4 of 26 Revision 0 P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
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SITE DETAILS
2.1. Existing Site Description
Lot 13 (RP150347), located at 16 Rene Street, covers an area of 1298m², including an existing
building with a roof area of 350.5m² and impervious ground surfaces covering 265.2m² of the site
(total impervious area of 615.7m²). The site contains an easement housing existing sewer and
stormwater along the southern boundary of the property. The subject land falls east towards Rene
Street at grades of typically 4%. The upstream run-off from the Council works depot site at the
western boundary is intercepted by a concrete spoon drain in the adjacent property so no upstream
flows are expected to encumber the site.
2.2. Existing Drainage Patterns
The surface run-off from the existing site is captured in inlet pits within the existing driveway and a
trench drain at the driveway access that discharge to the Council stormwater infrastructure within
Rene St. At the rear of the site to the west, a small earthen bund at the approximate location of the
edge of the easement separates run-off running within the easement area from the run-off within the
rest of the site.
Roof run-off from the building appears to be discharged through downpipes into the stormwater
drainage running through the easement at the south of the site.
Figure 2.1 - Site Locality Plan (Noosa Council Intramaps, 2021)
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2.2.1 Stormwater Catchments
Figure 2.2 – Existing Catchments Plan
2.3. Proposed Development Drainage Pattern
2.3.1 Stormwater Concept
Stormwater run-off from the new caretaker building roof area will be conveyed into a single 7.5kL
rainwater tank. The tanks will be plumbed for internal reuse in toilets and laundry areas, with 3.75kL
of the tank allocated for reuse, and the remaining 3.75kL dedicated to attenuating the roof run-off.
To minimise pollutants entering the tank, first flush diverters will be installed to divert the initial
capture of roof water to irrigation of the vegetated areas on site.
Run-off from the new driveway area will be graded to fall towards a bioretention area to the west of
the existing building for water quality treatment. A trench drain at the edge of the existing pavement
will be provided to ensure that the majority of run-off from the proposed driveways at the rear of the
site will be treated prior to discharge from the site. The bioretention area inlet pit will connect into
the drainage line within the easement, where it will be discharged from the site as the legal point of
discharge for the proposed development area.
The roof and allotment drainage system for the proposed site shall be designed to comply with:
1. Noosa Shire Council Planning Scheme Policy (PSP) - Engineering Design Standards – Roads,
drainage and earthworks;
2. The Queensland Urban Drainage Manual (QUDM); and
3. AS/NZS 3500.3:2015 - Plumbing and Drainage Part 3: Stormwater Drainage.
Refer to Appendix A Proposed Stormwater Layout Plan for the proposed stormwater drainage
layout plan.
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2.3.2 Stormwater Catchments
A schematic layout plan of the proposed development and its drainage catchments as described in
the previous sections is shown below in Figure 2.3 – Proposed Catchments Plan.
Figure 2.3 – Proposed Catchments Plan
2.4. Flood Considerations
Review of the Noosa Shire Council Intramaps flood layers including the Flood Hazards Overlay has
identified that the site is located outside of any flood or inundation areas within the locality indicating
it is not expected that that the proposed development will be subject to flooding.
2.5. Acid Sulphate Soils
Review of the Noosa Shire Council Intramaps Land Subject to Acid Sulphate Soils Overlay identifies
that the site is located within Area 2 of the overlay, for lands between 5m AHD and 20m AHD. Acid
Sulphate Soil testing is typically required in areas with surface levels less than 5.0m Australian Height
Datum (AHD) as stated in the State Planning Policy 2017. The requirements for acid sulphate testing
are to be assessed by a geotechnical engineer prior to the detailed design stage of this proposed
development.
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Figure 2.4 – Land Subject to Acid Sulphate Soils Overlay (Colour indicates above 5m AHD to 20m AHD) Project number 20210121 File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 8 of 26 Revision 0 P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
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STORMWATER QUANTITY
3.1. Pre-Post Comparison
The site conditions were modelled using the Watershed Bounded Network Model (WBNM) software
in combination with Storm Injector. This combination allows the site to be modelled to determine the
critical storm events for the existing site and the proposed development to assess whether there is
an increase to the peak run-off and if so, to determine the level of stormwater detention required to
ensure peak outflows from the site are not increased.
The models have been run using the ensemble of storm events for 63.2%, 50%, 20%, 10%, 5%, 2%
and 1% Annual Exceedance Probability (AEP) for durations from 1 minutes to 12 hours to
determine the critical storm duration and the mean peak flowrate from the storms. The parameters
obtained from the Australian Rainfall and Runoff (ARR) Data Hub for the location and the rainfall
data obtained from the Bureau of Meteorology have been used to generate the storms.
As identified in the Noosa Shire Council Works Code, climate change impacts are to be accounted
for in the stormwater modelling. Discussions with Council have indicated that a 20% increase to the
Bureau of Meteorology rainfall data will provide an acceptable allowance, therefore the rainfall data
has been increased by 20% for all storm events to account for this.
Both the existing and developed site have been modelled as a single catchment representing the full
site with the actual impervious fractions determined from the site survey and the proposed design
plans. A catchment lag parameter of 1.6 has been applied along with a non-linearity parameter of
0.77 as recommended by the ARR Guide to Flood Estimation Book 7 Application of Catchment
Modelling Systems. The modelling parameters and rainfall intensities used are provided in Appendix
B WBNM Modelling Parameters.
The hydrographs and box plots of the different storm events for the critical storms for the existing
site and the proposed development site based on this modelling are provided in Figure 3.1 – Pre-
development site critical storm rainfall hydrographs showing peak flow rates and Figure 3.2 – Post-
development site critical storm rainfall hydrographs showing peak flow rates.
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Figure 3.1 – Pre-development site critical storm rainfall hydrographs showing peak flow rates
Figure 3.2 – Post-development site critical storm rainfall hydrographs showing peak flow rates
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The results of the modelling against the range of design storms for the development under the
existing and proposed development conditions are shown in Table 3.1 Existing and proposed
unmitigated site peak discharge rates.
Table 3.1 Existing and proposed unmitigated site peak discharge rates
16 Rene Street
Qchange
A.E.P Qexisting Qproposed Qchange (%)
(m³/s) (m³/s) (m³/s)
63.20% 0.031 0.034 0.003 10%
50% 0.038 0.040 0.002 5%
20% 0.062 0.065 0.003 5%
10% 0.077 0.082 0.005 6%
5% 0.093 0.094 0.001 1%
2% 0.106 0.108 0.002 2%
1% 0.116 0.121 0.005 4%
As is expected, the increased impervious area will generate a higher peak storm discharge that will
require attenuation to ensure no worsening of the current run-off from the site.
The post-development model was updated to provide storage through a rainwater tank with
attenuation storage connected to the new roof area, as well as the storage provided by the
bioretention area for surface run-off. An iterative process was used to determine a suitable
configuration of storage volume, low-flow, and high flow pipe outlets for the rainwater tank to deliver
the required reduction of the flow rates from the site.
The tank has been modelled as a 7,500L rainwater detention tank. A low flow outlet with 25mm orifice
plate is provided at half the tank height with the volume below the low flow assumed to be full at the
time of the stormwater. A high flow 90mm diameter outlet at the top of the tank acts as the overflow
for larger storm events.
The bioretention area has been modelled based on the sizing determined through MUSIC modelling
to deliver the required stormwater quality improvements. A 5m² area is modelled with a low flow
100mm diameter slotted ag pipe at the base of the garden, and the inlet pit operating as a weir inlet.
A 600mm media filter depth with an assumed porosity of 0.3 and the extended detention depth of
200mm provides the storage capacity for the bio-garden.
Using this combination of parameters, has been found to achieve the desired results as shown below
in Table 3.2 Existing and proposed mitigated site peak discharge rates. The resulting hydrograph is
shown in Figure 3.3 – Mitigated post development site critical storm rainfall hydrographs showing
peak flow rates.
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Table 3.2 Existing and proposed mitigated site peak discharge rates
16 Rene Street
Qchange
A.E.P Qexisting Qproposed Qchange (%)
(m³/s) (m³/s) (m³/s)
63.20% 0.031 0.030 -0.001 -3%
50% 0.038 0.036 -0.002 -5%
20% 0.062 0.059 -0.003 -5%
10% 0.077 0.074 -0.003 -4%
5% 0.093 0.085 -0.008 -9%
2% 0.106 0.099 -0.007 -7%
1% 0.116 0.107 -0.009 -8%
Figure 3.3 – Mitigated post development site critical storm rainfall hydrographs showing peak flow rates
As the total peak flows are equal to or below the existing site conditions, the development suitably
controls the peak flow storm events from the development.
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STORMWATER QUALITY
The following sections discuss the stormwater quality considerations for the construction and
operational phase of the development.
4.1. Construction Phase
4.1.1 Erosion and Sediment Control Measures
During construction, it will be necessary to manage stormwater run-off to avoid potential
contamination of downstream waterways from sediments and other pollutants from the site. Best
practice erosion and sediment controls shall be installed to minimise the discharge of potential
contaminants from the site, in accordance with the objectives of Appendix 2 of the SPP (DERM, July
2017) shown below in Figure 4.1.
Figure 4.1 SPP 2017 Construction Phase Stormwater Management Design Objectives
A site-specific erosion and sediment control plan shall be prepared as part of a future submission for
Operational Works approval. Suitable erosion and sediment controls for the site may include:
1. Sediment fencing along downstream of the work areas within the site to prevent sediment
from leaving the construction area.
2. A shakedown area is to be installed at the construction entry/exit to the proposed
development area to minimise sediment being transported to and from the site.
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3. Ensuring any stockpiles and construction materials are contained using sediment fencing
downstream of these areas.
4. Downstream pits within the property to be protected through filter socks or similar.
4.2. Operational Phase
The development is to comply with the Noosa Council Water Quality and Drainage Code, AO6.2
which states:
“All stormwater runoff is treated to achieve maximum removal of nutrients, gross pollutants and
suspended solids as determined by cost to efficiency ratios. (e.g., bioretention basins must be sized
to achieve at least 80% reduction in total suspended solids, 60% reduction in total phosphorous, 45%
reduction in total nitrogen and 90% reduction in gross pollutants >5mm).”
It is proposed that the following measures to be implemented will provide the required level of
stormwater quality improvement to minimise impacts to the downstream network:
• First-flush divertors will be installed for roof-water drainage to divert initial run-off capture
to irrigation of the vegetated areas on site.
• A 7,500L Slimline Rainwater tanks will be used to capture roof run-off from the proposed
caretaker building, with 50% of the tank volume allocated to reuse, and 50% to attenuation
storage.
• A 5m² bioretention area will be used to treat and detain stormwater run-off from the newly
developed area prior to discharge from the site.
4.2.1 MUSIC Modelling
The proposed development and the above treatment train have been modelled in MUSIC (Model
for Urban Stormwater Improvement Conceptualisation) software in accordance with the Water by
Design MUSIC Guidelines 2018.
The climatic data has been modelled using the rainfall and PET data at station 40059 (Cooroy
Composite) in 6-minute timesteps. The rainfall run-off parameters have been set as defined for the
Southeast Queensland region, shown below in Figure 4.2 - Rainfall run-off parameters for SEQ.
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Figure 4.2 - Rainfall run-off parameters for SEQ
As the existing site is largely unchanged, only the proposed additions to the site have been
modelled The source nodes have been created using a split catchment approach with the
proposed new roof and driveway areas separated and modelled with stochastic pollutant
generation for each of the surface types as per Table 4.1 - Industrial Split Node Pollutant
Generation Parameters. The area and impervious fractions for each catchment are actual values
based on the design plans.
Table 4.1 - Industrial Split Node Pollutant Generation Parameters
Flow Type Surface TSS LOG¹º TP LOG¹º VALUES TN LOG¹º VALUES
Type Mean St. Dev Mean St. Dev Mean St. Dev
Baseflow Roof N/A N/A N/A N/A N/A N/A
Driveway 0.78 0.45 -1.11 0.48 0.14 0.20
Ground 0.78 0.45 -1.11 0.48 0.14 0.20
Stormflow Roof 1.30 0.44 -0.89 0.36 0.25 0.32
Driveway 2.43 0.44 -0.30 0.36 0.25 0.32
Ground 1.92 0.44 -0.59 0.36 0.25 0.32
The proposed treatment train has been modelled as shown in Figure 4.3 - MUSIC Stormwater
Treatment Train. The details of the treatments are described in the following sections
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Figure 4.3 - MUSIC Stormwater Treatment Train
4.2.1.1. Rainwater Tanks
The rainwater tanks connected to the source nodes representing their drained catchments. Each of
the tanks to be provided is modelled as a 3kL storage volume, with 1.5kL allocated for re-use
(assumed to be full at beginning of the modelling) and the remaining portion being for attenuation
capacity.
Figure 4.4 – 7.5kL Rainwater Attenuation Tank node configuration
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The tanks will be plumbed for internal reuse which has been modelled in accordance with the Water
by Design MUSIC Modelling guidelines. The reuse demands have been determined assuming the
caretaker facility would share similar characteristics to a 1 bedroom detached dwelling as follows:
- Internal Reuse
o All homes are assumed to be fitted with full water saving devices,
▪ 21L/Person/day for toilets
o 1-bedroom detached dwelling:
▪ 1.6 persons per dwelling
▪ 1.6 * 21L = 33.6L/day/unit
4.2.1.2. Bioretention Areas
A 5m² bioretention areas is to be provided within the property to capture and treat surface run-off
from the driveways as well as overflows from attenuation tanks. The bioretention areas are
modelled in accordance with the Water by Design MUSIC Guidelines 2018 with the node
configuration for one of the areas shown below in Figure 4.5 – Bioretention Node details.
Figure 4.5 – Bioretention Node details
Table 4.2 – Indicative Bioretention Area Plantings below (based on the Brisbane City Council Water
Sensitive Urban Design Engineering Guidelines) presents a sample of suitable plants that shall be
used to ensure the garden delivers effective nutrient removal in the bioretention areas.
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Table 4.2 – Indicative Bioretention Area Plantings
Planting
Density
Scientific Name Common Name Form Height (mm) (Qty/m²)
Myoporum parvifolium Creeping Boobialla Prostrate 150 4-6
Cymbopogon refractus Barbed Wire Grass Tufted 300 8-10
Cyperus polystachyos Bunchy Sedge Tufted 600 6-8
Dianella brevipendunculata Flax Lily Tufted 500 4-6
Dianella caerulea cv ‘Breeze’ Blue Flax-lily Tufted 600 4-6
Dianella caerulea cv ‘Little Jess’ Blue Flax-lily Tufted 400 4-6
Dianella longifolia var. longifolia Pale Flax-lily Tufted 550 6-8
Dichelachne crinita Long Haired Plume Grass Tufted 200 6-8
Erograstis elongata cv ‘Elvera’ Elvera Tufted 300 6-8
Imperata cylindrica Blady Grass Tufted 500 4-6
Lepidosperma laterale Variable Sword Sedge Tufted 750 8-10
Lomandra confertifolia Matting Lomandra Tufted 300 4-6
Lomandra confertifolia subs pallida Mat Rush Tufted 400 4-6
Lomandra longifolia Matt Rush Tufted 1000 4-6
Lomandra longifolia cv 'Tanika' Tanika Tufted 500 4-6
Poa labillardiere cv ‘Eskdale’ Eskdale Tufted 450 6-8
Themeda australis Kangaroo Grass Tufted 400 6-8
Themeda australis cv ‘Mingo Mingo Tufted 200 8-10
4.2.1.3. MUSIC modelling results
The proposed treatment train for each site can achieve the required water quality improvements as
shown below in Table 4.3 - MUSIC Modelling results for 16 Rene St.
Table 4.3 - MUSIC Modelling results for 16 Rene St.
Pollutant Sources Residual Percentage Percentage
Load Target Reduction
Total Suspended Solids (kg/yr) 94.482 13.132 80 86.101
Total Phosphorus (kg/yr) 0.177 0.046 60 74.01
Total Nitrogen (kg/yr) 0.912 0.492 45 46.011
Gross Pollutants (kg/yr) 8.119 0.313 90 96.142
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4.2.2 Operational Maintenance
Periodic maintenance and monitoring of the bioretention area proposed for this development shall
be carried out to ensure it is operating effectively during the operational phase. The responsibility
for these maintenance activities shall be the body corporate or owner of the site.
The bioretention areas shall be maintained following a schedule of routine inspections undertaken
after every significant rainfall event (30mm of rainfall in a 24-hour period) or on a three-monthly
basis within the first twelve months and on a six-monthly basis thereafter. The inspection shall
ensure the proper functioning and condition of the bioretention area and ensure that the planting
and vegetation health is suitably maintained. An inspection checklist from the Healthy Waterways
Technical Design Guidelines for Southeast Queensland has been provided in Appendix C
Bioretention Inspection Checklist that provides the structure for the inspections to be undertaken.
In addition to regular inspections, the first 4 months of establishment of the bioretention areas
requires a watering frequency of:
i. Week 1 - 6: 5 times per week
ii. Week 6-10: 3 times per week
iii. Week 11-15: 2 times per week
After 5 months, watering frequency shall be adjusted based on the local conditions to ensure plants
are maintained in a healthy state.
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CONCLUSION
This Stormwater Management Report has outlined how the stormwater run-off from the site is to be
managed to comply with the relevant requirements and minimise any adverse impacts to the
downstream catchments.
• The existing site surface run-off is captured internally and discharge into the Council
stormwater infrastructure on Rene St and within the easement on the property.
• The proposed legal point of discharge for the newly developed area of the site will be the
stormwater network within the easement on the property.
• The existing and proposed development site have been modelled for the critical design
storm events for the site, which found attenuation would be required. Provision of a 7.5kL
rainwater attenuation tank with 3.75kL of attenuation storage was found to provide suitable
mitigation to the development to ensure that there will be no increase to existing peak flow
discharges from the site for any of the storm events.
• During construction, erosion and sediment control measures are to be implemented to
minimise potential contaminants impacting the downstream receiving environment. An
erosion and sediment control plan shall be developed as part of a submission for Operational
Works approvals.
• In the operational phase of the development, a stormwater treatment train will provide
quality improvements as required by the Noosa Council Planning Scheme Policy. Roof run-
off from the new caretaker’s facility will be captured in a 7,500L rainwater reuse and
attenuation tanks. The tank is to be plumbed for reuse in internal toilets, serving to provide
both treatment and reduce the volume of run-off leaving the site. Overflows from the tanks,
as well as the surface run-off from the driveway will be directed toward a 5m2 bioretention
areas providing the required treatment for the proposed development. Outflows from the
bioretention area will be discharged through the stormwater infrastructure in the drainage
easement within the property
By implementing the proposed stormwater treatments, the development will reduce the
quantity of stormwater pollutants by more than 90% of gross pollutants, 80% of total
suspended solids, 60% total phosphorous and 45% total nitrogen, exceeding the pollutant
reduction targets required for the site.
• The proposed stormwater solution is considered to minimise any adverse impacts to the
downstream environment arising from the stormwater run-off while also meeting the
stormwater quality targets required for the development.
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Appendix A Proposed Stormwater Layout Plan Project number 20210121 File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 21 of 26 Revision 0 P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
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PRELIMINARY
NOT FOR CONSTRUCTION
100mm GRATED BIORETENTION GARDEN
TRENCH DRAIN
EXISTING TRENCH DRAIN
PROVIDE 7,500L SLIMLINE DRIVEWAY
RAINWATER ATTENUATION
TANKS AS PER DETAIL B.
RAINWATER TANK
OVERLAND FLOW DIRECTION
PROPOSED NEW
DRIVEWAY DRAINAGE LINE
PROPOSED
CARETAKERS
BUILDING
EXISTING
COVERED
5m² BIORETENTION AREA. BUILDING
CARETAKERS
CAR PARK 600MM FILTER MEDIA
200MM EXTENDED DETENTION DEPTH
REFER TO DETAIL A.
TANDEM CAR
PARK
STORM WATER PIT
APPROX STORM WATER LINE
PROVIDE 600x600 GRATED INLET
SMH CLASS B GRATED LID
APPROX SEWER LINE
SMH
EXTENDED DETENTION
NOMINAL 200MM
PLANTING SPECIES TO PROVIDE EFFECTIVE
REMOVAL OF NUTRIENTS. PLANT VARIETIES
MAINTENANCE HATCH AND PLANTING DENSITIES TO ARCHITECTURAL
SECURE CAPPED END WITH
SCREWS
SPECIFICATIONS
LOW FLOW JUNCTION WITH SCREW CAP DETAIL DO NOT SCALE, IF IN DOUBT ASK!
NTS
600x600 RAISED GRATE ORIFICE PLATE DISK WITH 100Ø HIGH FLOW OUTLET ROOF DOWNPIPE CONNECTION TO HYDRAULIC
FIELD INLET PIT S.L. 25mm ORIFICE ENGINEERS SPECIFICATIONS
1 IN
4 MA
X MAX HIGH FLOW
1 IN 4 EXTEND GEOFABRIC 500MM TANK WALL
OUTLET
AND PIN UNDER TOPSOIL
RETENTION LEVEL 7,500L SLIMLINE RAINWATER TANK
SCREW ON
500MM SANDY LOAM FILTER MEDIA ACCESS CAP
(0.45MM AVERAGE PARTICLE SIZE) ATTENUATION
VOLUME 3.75KL 0 8/10/21 INITIAL PREPARATION BP MP
Rev Date Description By Chk
OUTLET TO
DRAINAGE
NETWORK
100MM COARSE SAND TRANSITION ORIFICE DISK TO BE GLUED INSIDE RAINWATER REUSE VOLUME
FILTER MEDIA JUNCTION. uPVC OUTLET FROM TANK 3.75KL
(NOMINAL SIZE 0.5 - 2MM) TO BUTT UP AGAINST ORIFICE DISK
PROVIDE PROVIDE SLOTTED SUBSOIL DRAIN AT
END CAP MIN 0.5% GRADE TO PIT NOMINAL 200MM GRAVEL DRAINAGE LAYER [email protected]
(FINE AGG., NOMINAL SIZE 2 - 5MM)
37 MARY ST NOOSAVILLE, QLD
BIDIM A34 GEOFABRIC OR SIMILAR 07 5211 1003
SUBSOIL DRAIN CLEANOUT TO BE WRAPPED AROUND
WALLS AND BASE OF FILTER MEDIA
DETAIL B - RAINWATER ATTENUATION TANK Client
(NON-SLOTTED PVC) AND 135° ELBOW NTS RG STRATEGIC
CONNECTOR
Project Name
SCOOTER STYLE
16 RENE ST
DETAIL A -BIORETENTION AREA DRAINAGE NOTES SUBJECT STRUCTURE TO BE CONSTRUCTED TO.
7. CONTRACTOR TO ENSURE ALL MANHOLE AND PIT STRUCTURES COMPLY WITH THE MAXIMUM DEPTH SPECIFIED NOOSAVILLE 4566 QLD
NTS BY THE LOCAL AUTHORITY FROM FINISHED SURFACE LEVEL TO UNDERSIDE OF SLAB. ANY NON CONFORMANCE
1. BUILDING DRAINAGE TO BE DESIGNED BY HYDRAULIC CONSULTANT. Title
IS TO BE RECTIFIED AT THE CONTRACTORS EXPENSE.
2. ALL STORMWATER PIPES ARE TO BE MANUFACTURED TO RELEVANT AUSTRALIAN STANDARDS INCLUDING BUT PRELIMINARY STORMWATER LAYOUT
NOT LIMITED TO AS4058 AND AS1992. 8. THE CONTRACTOR IS TO CONFIRM THE LOCATION OF SERVICE CONDUITS WITH THE SUPERINTENDENT PRIOR
TO LAYING STORMWATER DRAINAGE. ALL TRENCH EXCAVATION AND CONSTRUCTION SHALL COMPLY WITH THE
3. CONTRACTOR TO CONFIRM LOCATION AND LEVEL OF EXISTING STORMWATER DRAINAGE WHERE CONNECTING REQUIREMENTS OF THE QUEENSLAND WORKPLACE HEALTH AND SAFETY ACT 2011.
ON TO EXISTING AND NOTIFY ENGINEER OF ANY CONFLICTS.
9. REFER TO ARCHITECTURAL PLANS FOR ALL DIMENSIONS.
4. ALL STORMWATER GRATES/LIDS WITHIN TRAFFICABLE AREAS TO BE CLASS "D" IN ACCORDANCE WITH AS3996.
5. ALL GRATES AND LIDS SHALL SIT FLAT WITH ITS SURROUND AND NOT BE LOOSE OR MOVE UNDER WHEEL Project No. Discipline Status
LOADS. 20210121 CIVIL PRELIMINARY
6. ALL STORMWATER STRUCTURES TO BE CONSTRUCTED IN ACCORDANCE WITH LOCAL AUTHORITY GUIDELINES Designed By Drawn By Scale
(at
AND SPECIFICATIONS. WHERE STRUCTURES EXCEED MAXIMUM DEPTH AS IDENTIFIED WITHIN STANDARD B.PARRY J.CARR 1:100 A1)
DRAWINGS THE CONTRACTOR WILL ENSURE AN ADEQUATE STRUCTURAL DESIGN IS UNDERTAKEN FOR THE
Drawing No. Revision
S01.01 1
FULL SIZE ON ORIGINAL 0 10 20 30 40 50 60 70 80 90 100 mm
Page 24
Appendix B WBNM Modelling Parameters Project number 20210121 File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 22 of 26 Revision 0 P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
Page 25
Modelling Parameters Project number: 20210121 Street Address: 16 Rene St, Noosaville Locality: Noosaville, Noosa Shire Council Storm Injector Configuration
Page 26
Modelling Parameters
Project number: 20210121
Street Address: 16 Rene St, Noosaville
Locality: Noosaville, Noosa Shire Council
ARR Datahub Parameters
Input Data Information Storm Losses Temporal Patterns
Latitude: -26.413755 Storm Initial Losses 27 Code EC North
Longitude: 153.042472 Storm Continuing Losses 2.6
WBNM Parameters
Catchments
Existing Site Developed Site Existing Site Developed Site
Area 0.013 0.013 Non-Linearity Exponent 0.77 0.77
Fraction Impervious 47.39 67.3 Initial Loss (Base*) 27 27
Lag Parameter 1.6 1.6 Continuing Loss 2.6 2.6
Impervious Lag Factor 0.1 0.1 Impervious Initial Loss 0 0
* Initial loss used in models is reduced by pre-burst storm event
OSD
Roof Tank Biogarden
Storage H S Storage H S
0 0 0 0 0 0
1 1 0.00375 1 0.6** 0.009
2 2 0.075 2 0.8 0.0019
3 1 0.0029
** assumed media porosity of 0.3
Low Flow Diameter 25 mm Low Flow Diameter 100 mm
Low Flow Elevation 1m Low Flow Elevation 0m
High Flow Diameter 90 mm Weir Length 2.4 mm
High Flow Elevation 1.9 m Weir Elevation 0.8 m
Pervious Flow to OSD 0% Weir Coefficient 1.66
Impervious Flow to OSD 14.54 % Pervious Flow to OSD 0%
Impervious Flow to OSD 29.54 %
Page 27
Rational Method Calculations
Project number: 20210121 Calculations: B. Parry
Street Address 16 Rene St Date: 7/10/2021
Locality: Noosaville, Noosa Shire Council
Site Area Composition
Existing Site Roof Area: 350.5 m2 Developed Site Roof Area: 477.62 m2
Existing Site Paved Area: 265.19 m2 Developed Site Paved Area: 396.28 m2
Existing Site Total (Impermeable): 615.69 m2 Developed Site Total (Impermeable): 873.9 m2
Existing Site Total (Permeable): 683.3445 m2 Developed Site Total (Permeable): 425.1345 m2
Total Site Area: 1299.0345 m2 Increase Impermeable Area: 258.210 m2
0.026 Ha.
Time of Concentration
Existing Site Proposed Site
tc 5.0 mins tc 5.00 mins
Rational Method - Peak Flow Calculation
Existing Site Proposed Site
Area (Ha.) 0.130 Ha. Area 0.130 Ha.
fi 0.474 Fi 0.673
1 1
I10 80.987 mm/hr I10 80.987 mm/hr
C10 0.79 C10 0.83
A.E.P Fy Cy Iy Qy (m3/s) A.E.P Fy Cy Iy Qy (m3/s)
63.2% AEP 0.8 0.636 135.16 0.031 63.2% AEP 0.8 0.668 135.16 0.033
50% AEP 0.85 0.676 152.60 0.037 50% AEP 0.85 0.709 152.60 0.039
20% AEP 0.95 0.755 208.19 0.057 20% AEP 0.95 0.793 208.19 0.060
10% AEP 1 0.795 245.25 0.070 10% AEP 1 0.835 245.25 0.074
5% AEP 1.05 0.835 280.13 0.084 5% AEP 1.05 0.876 280.13 0.089
2% AEP 1.15 0.914 325.91 0.107 2% AEP 1.15 0.960 325.91 0.113
1% AEP 1.2 0.954 360.79 0.124 1% AEP 1.2 1.001 360.79 0.130
Page 28
Rational Method Calculations
Project number: 20210121 Calculations: B. Parry
Street Address 16 Rene St Date: 7/10/2021
Locality: Noosaville, Noosa Shire Council
Validation of Pre-Development Model Pre / Post Comparison
A.E.P Q (m3/s) - WBNM Q (m3/s) - Rational Differential A.E.P Qy Pre (m3/s) Qy Post (m3/s) Qchange (m3/s) Qchange (%)
63.2% AEP 0.031 0.031 0% 63.2% AEP 0.031 0.034 0.003 10%
50% AEP 0.038 0.037 -3% 50% AEP 0.038 0.040 0.002 5%
20% AEP 0.062 0.057 -8% 20% AEP 0.062 0.065 0.003 5%
10% AEP 0.077 0.070 -9% 10% AEP 0.077 0.082 0.005 6%
5% AEP 0.093 0.084 -10% 5% AEP 0.093 0.094 0.001 1%
2% AEP 0.106 0.107 1% 2% AEP 0.106 0.108 0.002 2%
1% AEP 0.116 0.124 7% 1% AEP 0.116 0.121 0.005 4%
Validation of Post-Development Model Pre / Post (OSD) Comparison
A.E.P Q (m3/s) - WBNM Q (m3/s) - Rational Differential A.E.P Qy Pre (m3/s) Qy OSD (m3/s) Qchange (m3/s) Qchange (%)
63.2% AEP 0.034 0.033 -3% 63.2% AEP 0.031 0.030 -0.001 -3%
50% AEP 0.040 0.039 -3% 50% AEP 0.038 0.036 -0.002 -5%
20% AEP 0.065 0.060 -8% 20% AEP 0.062 0.059 -0.003 -5%
10% AEP 0.082 0.074 -10% 10% AEP 0.077 0.074 -0.003 -4%
5% AEP 0.094 0.089 -5% 5% AEP 0.093 0.085 -0.008 -9%
2% AEP 0.108 0.113 5% 2% AEP 0.106 0.099 -0.007 -7%
1% AEP 0.121 0.130 7% 1% AEP 0.116 0.107 -0.009 -8%
Page 29
IEDs Frequent and Infrequent Storm Events vw
Project number: 20210121 ae
street Address: 16 Rene St, Noosaville aT
Locality: Noosaville, Noosa Shire Council
Source Http://www bom gov.au/water/designRainfalls/revised-ifd/
Location: Latitude
26.4138,
Longitude
153.0425
Date obtained: 07/10/2021
Annual Exceedance Probability (AEP) Annual Exceedance Probability (AEP) + 20% climate change increase
Duration 63% 50% 20%" 10% 5% 2% 1% 63% 50% 20%" 10% 5% 2% 1%
Lmin 170 193 262] 306| 349] 403} aaa] 185.3 210.37 285.58 333.54 380.41 439.27 483.96
2 min 144 164 227] 270) 312] 369] aaa) 156.96| 178.76| 247.43 294.3 340.08 402.21 451.26
3 min 136 154 212] 252] 230) 342] 381] 148.24] 167.86| 231.08 274.68 316.1 372.78 415.29
4 min 129 147 201) 237] 272! 319] 354] 140.61 160.23 219.09 258.33 296.48 347.71 385.86
5 min 124.00 140.00 191.00 225.00 257.00 299.00 331.00 135.16 152.60 208.19 245.25 280.13 325.91 360.79
10 min 101 114 154 180 204] 235| 258] 110.09 124.26| 167.86| 196.2) 222.36 256.15 281.22
15 min 85.7 96.9 131 152 173 199 217] 93.413 105.621 142.79 165.68| 188.57 216.91 236.53
20 min 74.8 84.6 14 133 151 174 191 81.532 92.214 124.26| 144.97 164.59 129.66| 208.19
25 min 66.7 75.4 102 119 136 157 172 72.703 82.186 111.18| 123.71 148.24] 171.13 187.48|
30 min 60.4 68.3 92.6 109 124 143 158 65.836 74.447 100.934] 118.81 135.16| 155.87 172.22
45 min 477 54.2 74 37.2 100 117 129 51,993 59.078 80.66 95.048 109 127.53 140.61
TL hour 40.1 45.6 62.7 74.3 35.5 100 112 43.709 49.704 68.343 80.987 93.195 109 12.08|
1.5 hour B11 35.5 49.5 59] 68.4 a1 90.7 33.899 38.695 53.955 64.31 74.556 38.29 98.863
2 hour 26| 29.8 418 50.1 58.3 69.5 78.1 28.34 32.482 45.562 54,609 63.547 75.755 85.129
3 hour 20.2 23.2 33 39.8 46.7 56| 63.2 22.018 25.288 35.97 43.382 50.903 61.04 68.888
4.5 hour 15.7 18.2 26.2 318 37.4 45.1 51.2 17.113 19.838| 28.558 34.662 40.766 49.159 55.808
[6 hour 13.2 15.3 22.2 27.1 32, 38.7 aa 14.388] 16.677 24.198 29.539 34.88 42.183 47.96
9 hour 10.3 2 17.7 21.6 25.7 312 35.6 11.227 13.08| 19.293 23.544 28.013 34.008 38.804
12 hour 8.68 10.2 15 18.4 21.9 26.7 30.5 9.4612 1.118] 16.35] 20.056 23.871 29.103 33.245
18 hour 6.78 7.96 138 146 175| 21.4 24.5 7.3902 8.6764 12.862 15.914] 19.075 23.326 26.705
24 hour 5.67 6.65 9.93 12.3 1438 18.2 20.9 6.1803 7.2485 10.8237 13.407 16.132 19.838| 22.781
30 hour 491 5.76 8.63 10.7 12.9 15.9) 18.4 5.3519 6.2784 9.4067 11.663 14.061 17.331 20.056
36 hour 4.35 5.11 7.66 9.55 115 143 165| 4.7415 5.5699 3.3494 10.4095 12.535 15.587 17.985
48 hour 3.57 4.19 63 7.88 9.55 11.9) 13.9) 3.8913 4.5671 6.867 8.5892 10.4095 12.971 15.151
[72 hour 2.66 3.12 47 5.91 72 9.05 10.6 2.8994 3.4008 5.123 6.4419 7.848 9.8645 11.554]
{96 hour 2.14 25 3.7 4.75 5.8 7.33 8.6 2.3326 2.725 4.1093 5.1775 6.322 7.9897 9.374
120 hour 18 2.1 3.16 3.98 4.86 6.15 7.23 1.962] 2.289 3.4444 4.3382 5.2974 6.7035 7.8807
144 hour 155 1.82] 2.72 3.43 4.19 5.29 62 1.6895 1.9838| 2.9648 3.7387 4.5671 5.7661 6.758
168 hour 137] 16 24 3.02 3.68 4.62 5.41 1.4933 1744] 2.616 3.2918 4.0112 5.0358 5.8969
Page 30
Appendix C Bioretention Inspection Checklist Project number 20210121 File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 23 of 26 Revision 0 P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
Page 31
BIORETENTION SWALE MAINTENANCE CHECKLIST
3 to 6 Date of
Inspection Frequency:
monthly Visit:
Location:
Description:
Site Visit by:
INSPECTION ITEMS Y N ACTION REQUIRED (DETAILS)
Sediment accumulation at inflow points?
Litter within swale?
Erosion at inlet or other key structures?
Traffic damage present?
Vegetation condition satisfactory (density, weeds
etc)?
Replanting required?
Mowing required?
Clogging of drainage points?
Evidence of ponding?
Set down from kerb still present?
Damage/vandalism to structures?
Surface clogging visible?
Drainage system inspected?
Remulching of trees and shrubs required?
Soil additives or amendments required?
Pruning and/ or removal of dead or diseased
vegetation required?
Resetting of system required?
COMMENTS
Project number 20210121
File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 24 of 26
Revision 0
P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
Page 32
Appendix D Noosa Council Works Code Checklist Project number 20210121 File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 25 of 26 Revision 0 P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
Page 33
Stormwater drainage design Table 9.4.8.3 Criteria for assessment (part)
Performance Outcomes Acceptable Outcomes Response
Stormwater drainage design
PO1 AO1
The development and its stormwater management system is planned and A stormwater management plan is prepared consistent with PSP6 Engineering Design Standards - Roads, drainage and Complies - Refer to the SWMP that has been designed to be consistent with the PSP6 Engineering Design Standards -
designed having regard to: earthworks. Roads, drainage and earthworks and QUDM.
1. the natural features of the site;
2. the need to avoid impacts and potential risks to ecologically important
areas;
3. the likely effectiveness of erosion and sediment control and stormwater
drainage measures during rainfall events during and post construction; and
4. the need to protect environmental values and water quality of receiving
waters both during and post construction.
PO2 AO2.1
Stormwater drainage planning, design and construction is in accordance with PSP6 Engineering Design Standards -
Stormwater drainage infrastructure is planned, designed and constructed to: To be complied with at detailed design in conjunction with the SWMP
Roads, drainage and earthworks and the latest version of the Queensland Urban Drainage Design Manual.
1. incorporate allowance for increased flood risk and tidal inundation through
AO2.2
pipework as a result of cilmate change and sea level rise;
The stormwater drainage system connects to a lawful point of discharge in accordance with PSP6 Engineering Design
2. ensure the development is adequately drained; and Complies - Stormwater drainage connects into existing Council owned stormwater drainage line
Standards - Roads, drainage and earthworks.
3. ensure stormwater is managed and lawfully discharged without altering
stormwater drainage characteristics external to the site.
AO2.3
Stormwater flows discharging from the development are demonstrated to be consistent with pre-development Complies - Refer to SWMP. The increase in flows arising from the development have been mitigated to pre-development
characteristics. levels.
AO2.4
Development provides for the management of stormwater to incorporate appropriate allowance for climate change
Complies - A 20% increase to rainfall intensities has been considered to account for climate change impacts. Refer to
impacts (including rainfall intensity and sea level rise), in accordance with PSP6 Engineering Design Standards – Roads,
SWMP.
Drainage and Earthworks.
Page 34
PO3 AO3.1
Stormwater drainage infrastructure conveys run-off in a manner that allows
Stormwater drainage infrastructure meets the desired standards of service for roads functionality set out in PSP6 Complies - The site captures and mitigates new run-off to pre-existing levels, and discharges into an existing Council
roads to deliver desired standards of service appropriate to the local conditions
Engineering Design Standards - Roads, Drainage and Earthworks. Stormwater network. Existing infrastructure will no be impacted by the development.
and local stormwater drainage characteristics.
PO4 AO4.1
Stormwater infrastructure is compatible with existing infrastructure, allows for
The location, design and construction of stormwater drainage structures is in accordance with PSP6 Engineering Design
easy access for the ongoing maintenance by Council, is cost effective across its To be complied with at detailed design in conjunction with the SWMP
Standards - Roads, drainage and earthworks.
design life.
AO4.2
Where infrastructure is located on private land an easement is dedicated over the infrastructure in accordance Complies - The stormwater solution proposes to connect into an existing drainage system within an easement through
with PSP6 Engineering Design Standards - Roads, drainage and earthworks. the property.
AO4.3
Any alterations or repairs to infrastructure as a result of the development are made at no cost to Council. To be complied with at detailed design in conjunction with the SWMP
AO4.4
Development avoids stormwater inflow and infiltration to the sewer infrastructure network. Complies - no stormwater discharged to sewer network.
AO4.5
Stormwater infrastructure is designed to minimise maintenance costs and the requirement for specialized equipment for Complies - Maintenance of the stormwater solution is the responsibility of the site owner and no additional
maintenance techniques. infrastructure is to be maintained by Council.
PO5 AO5.1
Stormwater drainage infrastructure is aligned to avoid crossing waterways,
wetlands, drainage lines and ecological important areas, or where it is Stormwater drainage infrastructure avoids crossing waterways, wetlands drainage lines and ecologically important areas
Complies - Refer to stormwater layout plan. No waterways or ecologically important areas are impacted.
demonstrated this is unavoidable, disturbed areas are reinstated and revegetated or follows the edge of existing disturbed areas.
upon completion of works.
AO5.2
Stormwater drainage infrastructure is co-located with other infrastructure within a combined utility corridor where
N/A - Stormwater is wholly contained within the proposed site.
appropriate.
AO5.3
Temporary vehicular crossings of waterways must be designed and constructed to be consistent with the current
N/A - No waterways are impacted by the proposed development.
International Erosion Control Association Best Practice Book Series.
Page 35
Stormwater quality and protection of receiving waters Table 9.4.8.3 Criteria for assessment (part)
Performance Outcomes Acceptable Outcomes
Stormwater quality and protection of receiving waters
PO6 AO6.1
Development is located, designed, constructed and operated to protect and
Stormwater runoff discharging into High Ecological Value waters as a result of development causes no increase in gross
enhance environmental values and water quality of waterways, wetlands, lakes, N/A - stormwater does not discharge into high ecological value waters.
pollutants, total suspended solids, total phosphorous or total nitrogen compared to a pre-development scenario.
ground waters and drainage systems.
AND
Editor’s note: Environmental values of waters and water quality objectives are
prescribed in Schedule 1 of the Environmental Protection (Water) Policy 2009 and
are identified on the State Planning Policy Interactive Mapping System.
AO6.2
All stormwater runoff is treated to achieve maximum removal of nutrients, gross pollutants and suspended solids as
determined by cost to efficiency ratios. (e.g. bioretention basins must be sized to achieve at least 80% reduction in total
Complies - refer to SWMP Quality section.
suspended solids, 60% reduction in total phosphorous, 45% reduction in total nitrogen and 90% reduction in gross
pollutants >5mm).
OR
AO6.3
Developments achieve a minimum 3 drop rating consistent with the Water by Design Living Waterways Scoring Guide
N/A
(Healthy Land and Water).
Editor’s note— PSP6 Engineering Design Standards - Roads, Drainage and Earthworks provides guidance on stormwater
design and modelling requirements.
PO7 AO7.1
Water quality treatment systems are designed to be integrated into the landscape consistent with the technical design
Water quality treatment systems use natural processes and materials, whenever
guideline published by Healthy Land and Water Water by Design for the feature. (eg. For Bioretention Basins:
possible, and are integrated into development to enhance biodiversity and Complies - Refer to SWMP for details.
Bioretention Technical Design Guidelines (October 2014) and for Wetland Systems the Wetland Technical
landscape benefits.
Design Guideline (May 2017).
PO8 AO8.1
Water quality treatment infrastructure to be dedicated as public assets are
Detailed life cycle costing is provided for the entire treatment train system including replacement costs of asset parts. N/A - no water quality treatment infrastructure is to be dedicated to council.
proven to be suitable for its use and of a cost effective and efficient standard.
AO8.2 Treatment systems dedicated as public assets are designed to minimise maintenance, renewal and adaption costs
N/A - no water quality treatment infrastructure is to be dedicated to council.
and the requirement for specialised equipment, material or maintenance techniques.
AO8.3
Vegetated stormwater management systems to be dedicated as public assets are established and maintained during the
maintenance period to ensure optimal vegetated growth and that the functional elements of the system achieve the N/A - no water quality treatment infrastructure is to be dedicated to council.
design function at the end of the maintenance period.
PO9 AO9.1
Free draining inlets and outlets are provided to ensure that waters do not pond for more than 24 hours. To be complied with at detailed design in conjunction with the SWMP.
Treatment systems are designed to eliminate or minimise health, safety and
aesthetic hazards, including risks associated with insect breeding, odour and
public safety.
AO9.2
Developments are designed to eliminate retaining walls in excess of 0.8m for any water quality treatment device. To be complied with at detailed design in conjunction with the SWMP.
Page 36
Hydrology and waterway stability Table 9.4.8.3 Criteria for assessment (part)
Performance Outcomes Acceptable Outcomes
Hydrology and waterway stability
PO10 AO10
Development prevents increased bed and bank erosion and sedimentation in
receiving waterways by avoiding changes in low rate, peak flow run-off and flow The development is designed to: Complies - Refer to SWMP for details.
duration.
1. limit the peak 1 year ARI event discharge within the receiving waterway to the pre-development peak 1 year
discharge;
2. maximise pervious areas by using pervious alternatives for otherwise impervious areas wherever possible;
3. provide for capture and reuse of stormwater for non-potable purposes for gardening, toilet flushing, laundry and
hot water supply uses;
4. incorporate appropriate detention features; and
5. incorporate natural channel design principles
Editor’s note: The Sustainable Building Design Code includes requirements for stormwater capture and reuse.
PO11 AO11.1
The design and construction of a natural channel or natural channel rehabilitation works are in accordance with the
Water sensitive urban design principles are applied to achieve multifunctional
Natural Channel Design Guidelines (Brisbane City Council) having regard to local topography, geology and N/A - No channels are proposed or impacted upon by the proposed development.
design of waterways, wetlands and drainage lines that provide for:
geomorphology.
1. stormwater conveyance that uses natural channel design;
2. protection of landscape features and ecological important areas including
terrestrial and aquatic habitat;
3. aesthetic and passive recreation values; AO11.2
4. flood management and conveyance of external catchment stormwater Landscape features, plant species and habitat types used in stormwater conveyance channels are complementary to the
To be complied with at detailed design in conjunction with the SWMP.
through the development; local context and natural waterways.
5. landscaping that incorporates local native species; and
6. bed and bank stability.
AO11.3
Bank and bed stability and planting densities result in a stable channel over the long term and minimal potential for pest
To be complied with at detailed design in conjunction with the SWMP.
plant species.
AO11.4
Water Sensitive Design measures are incorporated into the development, as detailed in the document Water Sensitive
Designs small improvements, new ideas, concepts and sketch designs for stormwater filtration systems (Healthy Complies - Refer to SWMP for water sensitive design measures incorporated into the solution.
Waterways Water by Design).
AO11.5
Floodplain management is designed in accordance with the Framework for the Integration of Flood and Stormwater
Management into Open Space published by Healthy Waterways Water by Design (version current at the time of N/A - Noosa Council mapping indicates that no flood plains are located within the development area.
development application)
Page 37
PO12 AO12.1
Where run-off from or within the site passes through or drains to natural channels, waterways or wetlands,
Development protects in-stream ecology by maintaining pre-development low N/A - Development will connect and drain into existing stormwater infrastructure and does not make use of natural
development protects in-steam ecology by maintaining pre-development low flow discharge regimes in accordance with
flow discharge regimes and maintaining fish passages. channels or waterways.
the frequent flow management objectives in PSP6 Engineering Design Standards - Roads, drainage and earthworks
AO12.2
Instream structures such as roads, bridges, culverts, and other stormwater infrastructure do not cause barriers to fish
N/A - No instream structures are proposed
passage and facilitate the movement of terrestrial and aquatic fauna along waterway corridors.
AO12.3
Benthic substrate retains a continuous grade with the direction of flow consistent with the natural bed profile. To be complied with at detailed design in conjunction with the SWMP.
PO13 AO13.1
Development is designed and constructed to maintain surface and ground water
The location and form of stormwater discharge points do not alter the pre-development hydrology of receiving surface Complies - Discharge from site is mitigated to pre-development levels and discharges into existing stormwater
balances that sustain the environmental values of water dependent ecosystems,
water or groundwater. infrastructure within the site.
including downstream aquatic, riparian, wetland and terrestrial ecosystems.
AO13.2
Developments located on groundwater recharge or discharge areas are designed and managed in accordance with a
groundwater recharge and discharge management plan prepared by a suitably experienced and qualified groundwater
N/A - Development is not located on groundwater recharge or discharge areas.
hydrologist. The groundwater recharge or discharge must demonstrate that the development does not affect
groundwater balances beyond the property boundaries.
Editor's Note— PSP6 Engineering Design Standards - Roads, drainage and earthworks provides guidance on prepare a
groundwater recharge and discharge plan.
Page 38
Construction and establishment of stormwater management systems Table 9.4.8.3 Criteria for assessment (part)
Performance Outcomes Acceptable Outcomes
Construction and establishment of stormwater management systems
PO14 AO14.1
Construction methods provide for appropriate controls to avoid entry and An erosion and sediment control plan prepared in accordance with the International Erosion Control Association Best
transport of litter, sediment, and associated prescribed water contaminants into Practice Books demonstrates that the capture and release of stormwater achieves the design objectives listed in Table A: To be complied with at detailed design in conjunction with the SWMP.
receiving waters. Construction phase – stormwater management design objectives of the State Planning Policy (Appendix 2 ).
Editor's note— Water contaminants are prescribed in the Environmental Editor’s note— PSP6 Engineering Design Standards - Roads, drainage and earthworks provides guidance on
Protection Act 1994. requirements for preparing an Erosion Management Plan.
AO14.2
Construction works are designed and managed to restrict the extent of clearing and soil exposure to the minimum
To be complied with at detailed design in conjunction with the SWMP.
necessary for access, and safe construction at any one time.
AO14.3
For buildings:
1. upstream runoff is diverted around the construction site; To be complied with at detailed design in conjunction with the SWMP.
2. sediment barriers are provided downslope of disturbed areas to prevent sediment washing into gutters, drains
and waterways , wetlands or drainage lines either on or off the site; and
3. temporary or permanent downpipes are connected to the stormwater system before laying the roof; or
4. localised erosion is avoided by directing flow from downpipes over non-erosive areas.
AO14.4
Chemical flocculants used as part of an erosion and sediment control plan do not harm the environmental values within
To be complied with at detailed design in conjunction with the SWMP.
receiving waters.
AO14.5
Appropriately sized litter containment areas, with provision for sorting recyclables are provided for the type of litter
To be complied with at detailed design in conjunction with the SWMP.
expected to be generated onsite.
Wastewater management and effluent disposal Table 9.4.8.3 Criteria for assessment (part)
Performance Outcomes Acceptable Outcomes
Wastewater management and effluent disposal
PO15 AO15
Development does not discharge wastewater unless it can be
demonstrated to not compromise environmental values of waters and Wastewater (non-sewage) generated from the development is collected and contained on-site, and is:
water quality objectives.
Editor’s Note— Environmental values of waters and water quality
objectives are prescribed in Schedule 1 of the Environmental Protection 1. lawfully disposed to sewer; or To be complied with at detailed design.
(Water) Policy 2009.
2. transferred off-site for treatment/disposal to an appropriately licenced facility;
3. reused on-site in a closed-cycle irrigation scheme, industrial processes, washing or cleaning or other purpose; or
4. treated to meet the drinking water supply environmental values prior to release.
Editor’s Note —The Plumbing and Drainage Act 2003 sets out requirements for wastewater management.
PO16 AO16
On-site effluent treatment and disposal systems are designed, constructed and
managed to not compromise the environmental values of waters and water An onsite effluent system and disposal area is: To be complied with at detailed design.
quality objectives.
1. not located on a slope greater than 1 in (10%);
2. not located at or below the 1% annual exceedance probability (AEP flood event);
3. not located within a riparian buffer area mapped on a Biodiversity, Waterways and Wetlands Overlay Map; and
4. setback 400 metres minimum from the full supply level of Lake Macdonald.
Editor’s Note— The Plumbing and Drainage Act 2003 sets out requirements for on-site effluent treatment and
disposal. The Queensland Plumbing and Wastewater Code and associated guidelines are used to confirm the suitability
of each site to accommodate an on-site sewerage facility; or where a centrally located group collection treatment system
is proposed, confirmation as to the suitability of the designated site to accommodate the on-site sewerage facility.
Additionally, where the combined total peak design capacity of effluent treatment is less than 21 equivalent persons, the
design of the system achieves a low to medium risk classification in accordance with Seqwater’s Land Use Risk Tool for
onsite sewerage facilities.
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Document prepared by RECOR Pty Ltd ABN 89 647 469 707 37 Mary Street Noosaville, QLD 4566 Australia T +61 7 5211 1003 E [email protected] W recorconsulting.com Project number 20210121 File RECOR Preliminary Stormwater Management Report - 20210121.docx, 2021-10-07 Page 26 of 26 Revision 0 P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
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