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LATE RFI - Revised SWMP
REC: waht 35 Pavillion Street, BT PLY Pla We Neil Gaghan Stormwater Management Plan May 2023
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Document control record
Document prepared by:
RECOR Pty Ltd
ABN 89 647 469 707
75 Noosa Drive
Noosa Heads, QLD 4567
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 Stormwater Management Plan
Document code 20220217-SWMP01 Project number 20220217
File path C:\12dS\data\RecorSYN\20220217 35 Pavillion St, Pomona_650\03 Engineering\02
Reports\20220217 Pavilion St SWMP.docx
Client Neil Gaghan
Client contact - Client reference -
Rev Date Revision details/status Author Reviewer Verifier Approver
(if required)
0 20/09/2022 Initial Version BP BP
1 26/05/2023 RFI Revision MR BP BP
Current revision 1
Approval
Author signature Approver signature
Name B. Parry Name B. Parry
RPEQ: 28084
Title Civil Engineer Title Civil Engineer
recorconsulting.com
P +61 7 5211 1003 A 75 Noosa Drive, Noosa Heads,Qld 4567
E [email protected]
Page 3
recorconsulting.com
P +61 7 5211 1003 A 75 Noosa Drive, Noosa Heads,Qld 4567
E [email protected]
Page 4
Contents
Introduction .................................................................................................................................... 5
Site Details...................................................................................................................................... 6
2.1. Existing Site Description & Drainage .................................................................................................. 6
2.2. Existing Drainage Patterns .................................................................................................................. 6
2.3. Proposed Development Drainage Pattern ......................................................................................... 7
Stormwater Quantity ....................................................................................................................... 8
3.1. Pre-Post Comparison........................................................................................................................... 8
3.2. Rainwater Reuse................................................................................................................................10
Stormwater Quality........................................................................................................................11
4.1. Construction Phase............................................................................................................................11
4.2. Operational Phase .............................................................................................................................12
Conclusion....................................................................................................................................13
Appendices
Appendix A
Proposed Development Plans
Appendix B
DRAINS Modelling Parameters and Results
Project number 20220217
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Page 5
INTRODUCTION
RECOR has been engaged to prepare a Stormwater Management Report to accompany a development application
for a 2-lot residential subdivision with access easement located at 35 Pavilion Street, Pomona.
This report investigates 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.
The original report has been updated to address stormwater matters raised by Noosa Council in their Information
Request dated 23/02/2023, as follows:
1. Provide clarification in regard to the “impervious areas” pre and post development.
2. Include the requirements of the Sustainable Building Code (water tanks) within the SMP
3. Provide additional comment on the impacts on the downstream property of the concentrated discharge and
the impacts on the future development potential of the adjoining land.
4. Indicate on the plans any necessary easements required to convey runoff from external to the site and within
the proposed new lots.
Project number 20220217
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SITE DETAILS
2.1. Existing Site Description & Drainage
The existing site, known in real property terms as Lot 3 RP 809059, is located at 35 Pavilion Street. The site contains
an existing an existing residential dwelling and secondary building, along with a free-standing shed structure. The
site covers an area of 2,574m² and is accessed by an easement over the existing driveway to Lot 4 RP 809059 (33
Pavilion Street). The site is located within an area zoned low density residential allotments, with dwellings to the
north, east and south, and undeveloped rural land to the west.
2.2. Existing Drainage Patterns
The natural grade of the subject site would typically be around 10% falling to the west, however the site area
containing the existing buildings has been flattened creating a level pad with grades of between 2% to 5% based on
contour mapping of the region. A locality plan for the site is presented below in Figure 2.1 - Site Locality Plan (Noosa
Council Intramaps, 2022).
Subject Site
Flow
Direction
Figure 2.1 - Site Locality Plan (Noosa Council Intramaps, 2022)
The run-off from the existing developed site typically drains overland as sheet flows following the existing
topography of the site towards the western boundary. Roof run-off is conveyed by downpipes which discharge
downstream of the dwelling to overland surface flows.
During inspection of the site, channelling of the driveway was observed that appears to indicate upstream flows from
the access driveway are discharging into the property, following the fall of the driveway through the site to the north.
Upstream flows from the adjacent properties to the east are also expected to flow through the site.
Project number 20220217
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2.3. Proposed Development Drainage Pattern
2.3.1 Stormwater Concept
The future sites will contain individual dwelling homes typical of low density residential allotments. The downstream
environment is typically rural in character however is zoned low density residential that may be developed in the
future.
The proposed internal drainage relies on overland surface flows from the proposed allotments to discharge run-off
from the development. Run-off from the roof area will discharge via downpipes to the ground through a gravel trench
to act as an energy dissipator. Impervious areas of development including the driveway will be graded to fall towards
the pervious ground area to the west with the overland flows remaining dispersed as they discharge downstream
consistent with the existing conditions.
Upstream flows from the existing access easement and adjacent properties to the east will be diverted around the
proposed lots along the northern site boundary. A table drain along the property boundary will carry run-off along
the eastern and northern boundary of the site. The run-off will be discharged through a level spreader positioned
along the western boundary of the site, distributing the flows over a minimum 4m width to minimise impacts to any
future downstream development and reducing risk of scour from the outlet. The table drain will be contained within
a drainage easement to the benefit of the upstream properties.
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 Development Plan for the proposed stormwater drainage layout plan illustrating
the concept described above.
2.3.2 Lawful Point of Discharge
The site typically drains west towards the large undeveloped rural parcel downstream of the site. The lawful point
of discharge test, as described in Section 3.9.1 of QUDM, requires:
• The development does not change the flow characteristics leaving the site; or
• The proposed development will not alter the sites stormwater discharge in a way that may substantially
damage a third-party property; or
• The location of the discharge from the site is under lawful control of the government or other statutory
authority from whom permission to discharge has been received; or
• An authority to discharge has been obtained.
An assessment of the site, considering a future impervious fraction of 40%, has found that total peak flows will
increase by an insignificant amount within context of the large allotments and low-density character of the locality.
Refer to Section 3.1 for details. As the peak increases are small for all events, attenuation is not considered
necessary to mitigate flows to predevelopment levels. Upstream flows which will be diverted around the proposed
allotments, are discharged at the downstream boundary by level spreader which will ensure the flows are
dispersed and unlikely to result in scour or concentrated flow paths that would impact upon the downstream
property.
The proposed discharge from the site will therefore not alter run-off conditions in a way that may substantially
damage third party property and the site will remain generally consistent with the existing drainage characteristics.
The proposed point of discharge is therefore able to achieve a lawful point of discharge for the development.
Project number 20220217
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STORMWATER QUANTITY
3.1. Pre-Post Comparison
An assessment of the existing and proposed site hydrological conditions has been carried out to determine the
impacts of the development upon peak flows from the site. The site has therefore been modelled using the DRAINS
software to determine peak flows under both scenarios to identify any attenuation requirements for the site.
An assessment of the potential future development of both lots has been undertaken to determine the impact of an
increased impervious catchment on the peak flow conditions. Each future lot will be a low-density residential site,
with lot area of over 1,000m². In accordance with Table 4.5.1 of QUDM and based on assessment of the surrounding
land use, an impervious fraction of 40% of the future lot will be assumed to be developed. Of this, it is assumed 70%
will be roof area made up of the dwelling, sheds and garage, 20% will be the driveway accesses to the properties
and 10% will be other impervious ground area such as pools, patios and footpaths.
In accordance with ARR2019, an Initial Loss-Continuing Loss (IL-CL) model has been used to assess the site against
the ensemble of storm temporal patterns for the East Coast North region. The loss parameters and temporal patterns
have been imported from the ARR Datahub, and rainfall intensities have been imported from the Bureau of
Meteorology IFD rainfall data allowing for a 20% increase to rainfall depths to account for future climate change
patterns.
The parameters obtained from the Australian Rainfall and Runoff (ARR) Data Hub for the location and the rainfall
IFD data obtained from the Bureau of Meteorology have been imported into DRAINS to generate the storm events.
The models have been run using the ensemble of storm events for 1EY, 50%, 0.2EY, 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. Refer to Appendix B DRAINS Modelling Parameters and Results for details
of the parameters used and summary of the results from the modelling.
A single catchment has been used to represent the existing and developed site conditions, with the areas for
impervious surfaces determined using survey data and architectural designs. The time of concentration for pre and
post development conditions has been calculated by DRAINS based on the estimated flow paths as follows.
• Pre-development
o EIA – 2 minute lag time for older roof drainage system + 26m overland flow at 3.5% on lawn
o RIA – 75m overland flow at 6.7% on gravel
o PA – 57m overland flow at 8.8% on lawn
• Post-development
o EIA – 1 minute lag time for new roof drainage system + 26m overland flow at 3.5% on lawn
o RIA – 50m overland flow at 8% on lawn
o PA – 50m overland flow at 8% on lawn
The configuration of the catchment areas for pre-development and post-development areas are shown in Figure 3.1
– DRAINS Pre-development catchment and Figure 3.2 – DRAINS Post-development catchments respectively.
Project number 20220217
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Figure 3.1 – DRAINS Pre-development catchment
Figure 3.2 – DRAINS Post-development catchments
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.
Table 3.1 Existing and proposed unmitigated site peak discharge
Pavilion Street
Qchange
A.E.P Qexisting Qproposed Qchange (%)
(m³/s) (m³/s) (m³/s)
63.2% AEP 0.035 0.033 -0.002 -6%
0.5 EY 0.052 0.057 0.005 10%
0.2 EY 0.081 0.084 0.003 4%
10% AEP 0.100 0.102 0.002 2%
5% AEP 0.124 0.126 0.002 2%
2% AEP 0.156 0.156 0.000 0%
1% AEP 0.172 0.172 0.000 0%
Despite the increase in impervious area, the combined effect of the changes resulting from the development will not
alter peak flows to a significant extent. The combined peak discharge from both lots increases the site run-off by a
maximum of 5L/s, or 2.5L/s for each lot. Within the context of the locality, being low density residential sites on large
allotments, this level of increase will not result in significant impacts or nuisance to the downstream nor damage to
the downstream property. Attenuation is therefore not considered necessary for the future development of the lots
where total impervious area of the lots is up to 40% impervious. Beyond this, further assessment may be necessary.
Project number 20220217
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3.2. Rainwater Reuse
In accordance with the Noosa Shire Council Sustainable Building Design Code AO2.1, rainwater reuse is required
for any future dwelling proposed on the new lot. This is to comprise of a minimum of 3,000L of rainwater storage to
capture and reuse for non-potable purposes including internal toilets and laundry supply as well as external
irrigation points. The 3,000L storage tank is to be connected to the maximum possible roof area of the proposed
dwelling.
Project number 20220217
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STORMWATER QUALITY
The following sections discuss the stormwater quality considerations for the construction and future operational
phase of the development.
4.1. Construction Phase
4.1.1 Erosion and Sediment Control Measures
During construction, it is necessary to manage stormwater run-off to avoid potential contamination of downstream
waterways from sediments and other pollutants from the site. A range of best practice sediment and erosion controls
should be implemented on the development to ensure negative impacts to the downstream receiving environment
are mitigated.
The works will involve only localised works to provide for drainage and driveway upgrades, therefore best practice
erosion and sediment control principles are considered suitable for the site to achieve the desired outcomes of
Appendix 2 of the SPP (DERM, July 2017), which are 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.
Project number 20220217
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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.
3. Diversion of upstream catchments around any exposed areas using diversion drains around the site.
4. Returfing or stabilisation of disturbed areas once earthworks and activities within that area are completed.
4.2. Operational Phase
The proposed works will involve and result in a residential dwelling on a large lot. The resulting pollutant
generation is considered consistent with the existing use of the site, and therefore no stormwater quality treatment
is proposed for the development.
Project number 20220217
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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.
• Due to the low-density nature of the proposed subdivision and surrounding sites, and lack of downstream
infrastructure, the internal drainage will rely on grading surfaces to discharge run-off as overland sheet flows
from the lots.
• The site has been assessed against potential future development of the lots assuming a 40% impervious
area. Modelling of the pre and post developed peak site run-off has found that the overall increase to
impervious peak flows as a result of this level of development will not significantly alter conditions from their
existing level, and therefore attenuation is not considered necessary for the future dwellings.
• A table drain upstream of a proposed access road will be provided along the eastern and northern property
boundaries, to intercept upstream flows and run-off from the existing access easement and divert them
around the future allotments. The discharge of this run-off will be dispersed by employing level spreaders
along the western property boundary to ensure the stormwater from the site is discharged as sheet flow
across the boundary, minimising potential flow concentrations or scour to the downstream property.
• During construction, best practice erosion and sediment control measures are to be implemented to
minimise potential contaminants impacting the downstream receiving environment achieving the objectives
of Appendix 2 of the SPP. An erosion and sediment control plan shall be developed as part of a submission
for Operational Works approvals.
• The proposed stormwater solution manages resolves a number of existing drainage issues within the site,
and the development will not result in significant impacts to water quality or quantity, and is therefore
considered to meet the Water Quality and Drainage objectives of the Noosa Plan.
Project number 20220217
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Appendix A
Proposed Development Plans
Project number 20220217
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LOT 4 SP179876
LOT 2 RP864877
LOT 4 RP864877
2m
DRAINA 59.97
3m GE EAS
EMENT
21.64
3m
LOT 2
1,430m²
20.29
3m
LOT 1 RP809059
53.85
3.5m
6.29
21.64
EASE SS &
LOT 1
MENT
1,144m²
E
SERV RED ACC
21.64
23 .07
ICES
HA
LOT 2 RP809059
6m S
52.1
6.02
EXISTIN
G ACCE
EASEM SS
ENT
LOT 4 RP809059
LOT 5 RP809059
CLIENT DETAILS: PROJECT ADDRESS: APPROVED BY: PROJECT NAME:
PROPOSED RESIDENTIAL SUBDIVISION
NEIL GAGHAN TITLE: STATUS:
35 PAVILION STREET PROPOSED LOT FOR APPROVAL - NOT FOR
© ABN 89 647 469 707
02 26/05/23 RFI UPDATE BRP BRP
POMONA, 4568, QLD BEN PARRY CONFIGURATION CONSTRUCTION
75 NOOSA DRIVE RPEQ: 28084
01 30/09/22 MCU ISSUE BRP MVP BRP SCALE: 1:250
NOOSA HEADS, QLD 4567
5 15 25m CPEng NER DRAWING NUMBER: PROJECT NUMBER: SHEET REV:
+61 7 5211 1003 REV DATE DESCRIPTION DWN CHK APP
DATE: 26/05/2023 SIZE:
RECORCONSULTING.COM REVISIONS
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010 20220206 A1 02
Page 16
S
97
96
89
8
93
97
91
90
92
96
S
97
S
94
TURNOUT DRAINAGE SWALE
THROUGH LEVEL SPREADER
SPILLWAY OF MINIMUM 4M
95
TYPICALLY AS PER IECA STD
DWG LS-01
S
S
MINIMUM 3KL RAINWATER REUSE
TANK TO BE PROVIDED FOR FUTURE
DWELLINGS ON NEW LOT. TANK TO PROVIDE TABLE DRAIN
BE CONNECTED FOR INTERNAL AND 300mm DEEP WITH 1V:2H
S
EXTERNAL NON-POTABLE REUSE BATTERS TO DIVERT
UPSTREAM RUN-OFF
97
UPSTREAM STORMWATER CATCHMENT
AREA: 0.25Ha
S
Fi: 31.0%
tc (FRIENDS EQN): 10 Min
Itc (1%): 235mm/hr
93
RATIONAL METHOD
S
1hr10: 65.2mm/hr
C10: 0.73
Fy: 1.2
CLIMATE FACTOR: 1.2
S
95
Qy = 1/360 * 0.25 * (1.2*0.73) * 235 *1.2
= 0.172m³/s
93
91
S
90
92
89
300mm 1V:2H
94
96
S
97
CHANNEL FLOW (MANNINGS EQN)
Sf: 4.4%
DEPTH: 0.30m
SIDE SLOPES: 1V:2h
S
BASE: 0m
WETTED PERIMETER: 1.34m
AREA: 0.18m²
HYDRAULIC RADIUS (A/P): 0.134m
MANNINGS n (GRASS): 0.035
S
CAUTION: SEWER LINE IN V: 1.57m/s
VICINITY. POTHOLE TO LOCATE FLOW CAPACITY (Qcap) = 0.283m²
AND ENSURE MINIMUM 600mm
COVER TO FINISHED SURFACE Qcap > Qmax = TRUE
S
98
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INDICATIVE NEW DRIVEWAY
92
LOCATION. FINAL DESIGN TO
BE CONFIRMED
93
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97
90
96
91
98
90
CLIENT DETAILS: PROJECT ADDRESS: APPROVED BY: PROJECT NAME:
PROPOSED RESIDENTIAL SUBDIVISION
NEIL GAGHAN TITLE: STATUS:
35 PAVILION STREET STORMWATER LAYOUT FOR APPROVAL - NOT FOR
© ABN 89 647 469 707
02 26/05/23 RFI UPDATE BRP BRP
POMONA, 4568, QLD BEN PARRY PLAN CONSTRUCTION
75 NOOSA DRIVE RPEQ: 28084
01 30/09/22 MCU ISSUE BRP MVP BRP SCALE: 1:250
NOOSA HEADS, QLD 4567
5 15 25m CPEng NER DRAWING NUMBER: PROJECT NUMBER: SHEET REV:
+61 7 5211 1003 REV DATE DESCRIPTION DWN CHK APP
DATE: 26/05/2023 SIZE:
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040 20220206 A1 02
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NOTE: INTERNAL LAYOUT FOR VISUALISATION ONLY
BASED ON 40% IMPERVIOUS AREA. FUTURE
DEVELOPMENT NOT CONFIRMED AS PART OF THIS
APPLICATION
93
93
95
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91
93
91
90
92
90
92
89
94
94
92
92
93
93
95
95
95
94
95
EXISTING SITE CONDITIONS ASSUMED FUTURE DEVELOPED SITE
(ASSUMED 40% IMPERVIOUS, 70% ROOF, 20% ROAD, 10% OTHER)
IMPERVIOUS GROUND AREA: 305.0m²
IMPERVIOUS GROUND AREA: 309.0m²
IMPERVIOUS ROOF AREA: 431.7m²
IMPERVIOUS ROOF AREA: 720.9m²
PERVIOUS GROUND AREA: 1,838m²
PERVIOUS GROUND AREA: 1,544.8m²
TOTAL SITE AREA: 2,574.7m²
TOTAL SITE AREA: 2,574.7m²
FRACTION IMPERVIOUS: 28.6%
FRACTION IMPERVIOUS: 40%
CLIENT DETAILS: PROJECT ADDRESS: APPROVED BY: PROJECT NAME:
PROPOSED RESIDENTIAL SUBDIVISION
NEIL GAGHAN TITLE: STATUS:
35 PAVILION STREET STORMWATER FOR APPROVAL - NOT FOR
© ABN 89 647 469 707
02 26/05/23 RFI UPDATE BRP BRP
POMONA, 4568, QLD BEN PARRY CATCHMENT PLAN CONSTRUCTION
75 NOOSA DRIVE RPEQ: 28084
01 30/09/22 MCU ISSUE BRP MVP BRP SCALE: 1:250
NOOSA HEADS, QLD 4567
5 15 25m CPEng NER DRAWING NUMBER: PROJECT NUMBER: SHEET REV:
+61 7 5211 1003 REV DATE DESCRIPTION DWN CHK APP
DATE: 26/05/2023 SIZE:
RECORCONSULTING.COM REVISIONS
DO NOT SCALE, IF IN DOUBT ASK
041 20220206 A1 02
Page 18
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FIGURE 3 - CONSTRUCTION VEHICLE (MRV) INTO SITE FIGURE 4 - CONSTRUCTION VEHICLE (MRV) OUT OF SITE
CLIENT DETAILS: PROJECT ADDRESS: APPROVED BY: PROJECT NAME:
PROPOSED RESIDENTIAL SUBDIVISION
NEIL GAGHAN TITLE: STATUS:
35 PAVILION STREET SWEPT PATHS FOR APPROVAL - NOT FOR
© ABN 89 647 469 707
POMONA, 4568, QLD BEN PARRY CONSTRUCTION
75 NOOSA DRIVE RPEQ: 28084
01 26/05/23 RFI UPDATE BRP BRP SCALE: 1:250
NOOSA HEADS, QLD 4567
5 15 25m CPEng NER DRAWING NUMBER: PROJECT NUMBER: SHEET REV:
+61 7 5211 1003 REV DATE DESCRIPTION DWN CHK APP
DATE: 26/05/2023 SIZE:
RECORCONSULTING.COM REVISIONS
DO NOT SCALE, IF IN DOUBT ASK
060 20220206 A1 01
Page 19
Appendix B
DRAINS Modelling Parameters and Results
Project number 20220217
Page 15 of 16
File 20220217 Pavilion St SWMP Rev1.docx, 2023-04-19 Revision 1
P +61 7 5211 1003 A 75 Noosa Drive, Noosa Heads,Qld 4567 E [email protected] recorconsulting.com
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Site Catchment Areas for DRAINS Modelling
Project number: 20220217 Calculations: B. Parry
Street Address: 35 Pavillion St
Locality: Pomona, NSC Date: 5/09/2022
Existing Site
Existing Site Directly connected (m²) Indirectly connected (m²)
35 Pavillion St Roof 431.7 431.7 -
Impervious Ground 99.4 - 99.4
Driveway 205.6 - 205.6
Total Imp 736.7 431.7 305.0
Total Per 1,838.0 - 1,838.0
Site Area 2,574.7 431.7 305.0
% impervious Effective DCIA = 75% DCIA ICIA +25% ineffective DCIA
323.8 412.9
Impervious 28.6% 12.6% 16.0%
Pervious 71.4%
Proposed Site
Assume Low Density Urban Residential - 40% impervious (QUDM Table 4.5.1.)
2 Lots
Proposed Directly connected (m²) Indirectly connected (m²)
35 Pavillion St Roof (70%) 720.9 720.9 -
Impervious Ground (10%) 103.0 - 103.0
Driveway (20%) 206.0 - 206.0
Total Imp 1,029.9 720.9 309.0
Total Per 1,544.8 - 1,544.8
Site Area 2,574.7 720.9 1,853.8
% impervious Effective DCIA = 75% DCIA ICIA +25% ineffective DCIA
540.7 489.2
Impervious 40.0% 21.0% 19.0%
Pervious 60.0%
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BOM IFDs Frequent and Infrequent Storm Events REC:<R Project number: 20220217 street Address: 35 Pavillion St Locality Pomona, NSC Date: 5/09/2022 Source : hitp://www-bom. gov.au/water/designRainfalls/revised-td/ Location: Latitude -26.35652646 tensity, “*AEP - Annual Exceedance Probability Nearest Latitude 26.3625 (5) 060 SEES EEE EEE Longitude 152.8590619 t noon Nearest Longitude 152.8625 (E) POON ones 4 + fee . 4 a a as00 | cena comes a: [4 Date obtained: 5/09/2022 3000 F- : 3 eons —— mm 750 —e— Annual Exceedance "any (SES y eee : —— ox [J Probability (AEP) Duration 63.20% 50% 20%* 10% 5% 2%. 1% 155; 175; 237] 277 35; 364 401 130 147, 199 235; 27 319 357 123 138 187 224 254 298] 332 17 132 179 210 244) 281 312 112 127] a7 203] 230 267 295 92.3 104 140) 164 186 214 235; 78.3 88.4 119 139 157 181 199 68.3 77 104) 121 137 158] 174 60.7 68.5 92.3 108] 123 142] 156 54.9 61.9 83.5 97.7 ay 129 142, [45 min 43.2 48.7 65.9 77.4 88.6 103| 14 ‘hour 36.1 40.7 55.3 65.2 74.9 87.7 97.5 1.5 hour 27.9 31.5 43.1 51d 59) 69.5 77.7 2 hour 23.2 26.3 36.1 43 49.8 59] 66.1 [3 hour 179 20.4 28.3 33.9 39.4 47 52.9 4.5 hour 13.9 15.9 22.4 26.9 315 37.7 42.6 [6 hour 17 13.4 19 23 26.9 32.4 36.7 [9 hour 9.13 10.6 15.2 18.5 21.8 26.3 29.8 12 hour 7.69 8.94 B 15.8 18.7 2.7 25.9 aspera sess 2 4 18 hour 6.03 7.05 10.4 127 15.1 18.5 2d [24 hour 5.05 5.93 a 10.9 B 15.9 18.2 : [30 hour, 4.38 5.16 771 9.55 ia 14.1 16.2 oz i oa + [36 hour, 3.89 4.59 6.89 8.56 10.3 127 147 [48 hour 32 3.78 5.72 744 861 10.7 Iai minutes hours I days [72 hour, 2.39 2.83 43 sal 655 8.22 3.6] [96 hour, 1.92 2.27 3.45 434 5.29 6.66 73 Duration 120 hour 1.62 19 2.88 3.63 442 557 653 144 hour 14 1.64 247 3 379 476 350 ‘©Copyright Commonwealth of Australia 2016, Bureau of Meteorology (ABN 92 637 533532) 168 hour 1.23 1.44 2.16 272 3.31 4.14 4.83
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ARR Datahub Parameters Project number: 20220217 Street Address: 35 Pavillion St Locality: Pomona, NSC Date: 5/09/2022
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90 (1.5) 120 (2.0) 180 (3.0) 360 (6.0) 720 (12.0) 1080 (18.0) 1440 (24.0) 2160 (36.0) 2880 (48.0) 4320 (72.0) (0.047) 06 (0.013) 04 (0.007) 34 (0.050) 95 (0.118) 13.2 (0.123) 7 (0.056) 1.9 (0.013) 0.4 (0.001) 0.0 (0.000) 0.0 (0.000) Interim Climate Change Factors 2030 2050 2070 RCP 4.5 0.869 (4.3%) 1.057 (5.3%) 1.272 (6.4%) 1.488 (7.5%) 1.676 (8.5%) 1.810 (9.2%) 1.862 (9.5%) (0.048) (0.048) 72 15 (0.111) (0.150) 58 94 (0.080) (0.109) 1.6 17.2 (0.136) (0.169) 18.3 24.1 (0.160) (0.175) 22.0 27.9 (0.142) (0.147) 17.9 25.0 (0.096) (0.109) 13.7 21.6 (0.065) (0.083) 16 19.1 (0.047) (0.062) 6.0 10.0 (0.022) (0.029) 17 28 (0.005) (0.007) RCP6 0.783 (3.9%) 1.014 (6.1%) 1.236 (6.2%) 1.458 (7.4%) 1.691 (8.6%) 1.944 (9.9%) 2.227 (11.5%) (0.048) (0.065) 15.7 14.4 (0.177) (0.138) 128 14.2 (0.128) (0.121) 22.6 23.6 (0.191) (0.167) 29.6 56.3 (0.183) (0.290) 33.5 58.7 (0.149) (0.215) 31.8 50.4 (0.117) (0.152) 29.4 62.4 (0.093) (0.137) 26.4 51.8 (0.071) (0.113) 13.8 39.9 (0.033) (0.078) 38 85 (0.008) (0.014) RCP 8.5 0.983 (4.9%) 1.349 (6.8%) 1.773 (9.0%) 2.237 (11.5%) 2.722 (14.2%) 3.209 (16.9%) 3.679 (19.7%) (0.074) 13.5 (0.116) 153 (0.116) 24.3 (0.153) 76.2 (0.347) 778 (0.250) 64.4 (0.169) 69.8 (0.159) 70.8 (0.134) 59.6 (0.100) 12.0 (0.017) Note Layer Info Time Accessed Version Note Preburst interpolation methods for catchment wide preburst has been slightly altered. Point values remain unchanged 05 September 2022 03:42PM 2019.1 ARR recommends the use of RCP4.5 and RCP 8.5 values. These have been updated to the values that can be found on the climate change in Australia website
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DRAINS Modelling Results
Project number: 20220217 Calculations: B. Parry
Street Address: 35 Pavillion St
Locality: Pomona, NSC Date: 5/09/2022
Pre / Post Comparison
3 3 3
A.E.P Qy Pre (m /s) Qy Post (m /s) Qchange (m /s) Qchange (%)
63.2% AEP 0.035 0.033 -0.002 -6%
0.5 EY 0.052 0.057 0.005 10%
0.2 EY 0.081 0.084 0.003 4%
10% AEP 0.100 0.102 0.002 2%
5% AEP 0.124 0.126 0.002 2%
2% AEP 0.156 0.156 0.000 0%
1% AEP 0.172 0.172 0.000 0%
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Document prepared by
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Noosa Heads, QLD 4567
Australia
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Project number 20220217
Page 16 of 16
File 20220217 Pavilion St SWMP Rev1.docx, 2023-04-19 Revision 1
P +61 7 5211 1003 A 75 Noosa Drive, Noosa Heads,Qld 4567 E [email protected] recorconsulting.com