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Response to Information Request 20220004 -Tunba Court
Attached to the e-mail Response to Information Request OPW21/0355 - 36 Tunba Court, Cooroy Mountain.
4th March 2022
Ref: OPW21/0355
Noosa Council
PO Box 141
TEWANTIN QLD 4565
Attention: Mark Lewis
Dear Sir,
Re: Information Request
At: 36 Tunba Court, Cooroy Mountain, QLD 4563
With reference to the abovementioned information request for the development
application (ref: OPW21/0355), we have been engaged to prepare additional information
and design plans to respond to your queries as follows:
2. Provide additional detail to demonstrate how the existing and proposed
works achieve compliance with:
2.1. The Earthworks Code – Performance Outcomes PO2, PO9 and PO11
PO2
Change to the levels on site do not have an adverse impact on the flooding and
drainage characteristics off-site.
The earthworks proposed as part of this operational works approval will not increase the
impervious surface area of the site, and run-off increases from any future development are
able to be catered for through the provision of rainwater reuse and attenuation tanks
sized based on the development’s characteristics.
Stormwater run-off from the earthworks pad are captured and conveyed by a concrete
spoon drain to a point of discharge at the north of the development area, where the
stormwater will be dispersed and energy dissipated through a rock energy dissipator
sized in accordance with QUDM for the peak 1% storm flow event to minimise impacts of
changes to the existing flow characteristics on the downstream environment. The point of
discharge is in line with the existing overland surface flows, therefore the changes to
earthworks levels are not considered to significantly alter the drainage characteristics or
flooding off-site.
P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
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PO9
On sloping sites development follows the natural landform wherever practical and
excavation or filling is minimal.
The development has sought to create a level pad surface area on steeply sloping hillside,
where following the natural landform would be impractical for this purpose. The
earthworks which have been initially constructed are proposed to be modified in
accordance with the Geotechnical Investigation Global Stability Assessment dated
November 21 by Morrison Geotechnic reducing fill batter slopes and providing benched
terraces between the cut slopes to ensure stability of the resulting earthworks.
PO11
Earthworks minimise any adverse impact upon groundwater, watercourses,
drainage lines, wetlands, and native vegetation.
The earthworks have been carried out clear of watercourses, drainage lines, wetlands and
native vegetation and are not expected to impact upon the vegetated area in proximity to
the lower fill batter.
The stormwater drainage system proposed for the earthworks has been designed in order
to maintain the pre-development characteristics in so far as is practicable. Stormwater run-
off that would have previously flowed overland into the vegetated area and gully to the
north of the earthworks continues to discharge towards the gully. An energy dissipator
provided at the outlet of the drainage system will minimise impacts of scour or erosion
and encourage dispersion of concentrated flows at the outlet so that impacts of the run-
off are reduced.
2.2. The Water Quality and Drainage Code – Performance Outcomes
PO1, PO2, PO5, PO6, PO10 and PO13.
PO1
The development and its stormwater management system is planned and designed
having regard to:
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.
The stormwater drainage for the development has been designed to minimise the
impacts of the development upon the downstream receiving waters and maintain the flow
characteristics of the downstream receiving environment as much as possible.
P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
Page 3
The proposed concrete spoon drain channels at the top of batters will convey stormwater
run-off from the upstream catchments and from the earthworks pad to the drainage gully
to the north of the development area which maintains consistency with the flow paths of
the pre-development site so that impacts to downstream environments and neighbouring
properties are minimised.
A rock energy dissipator has been sized in accordance with QUDM Section 8.7.2 to
ensure that the outlet of the drainage system is sufficiently protected such that the risks of
erosion or scour in the receiving waters are mitigated.
An erosion and sediment control plan has been prepared by Aussie Environmental to
manage the water quality of receiving waters during construction. Construction is to be
carried out in accordance with this plan to reduce impacts of the construction phase.
At the post construction phase, any disturbed or exposed areas of the development are to
be stabilised using grass seeding as soon as practicable to prevent sediment being lost
from the development site and stabilise the earthworks surface.
PO2
Stormwater drainage infrastructure is planned, designed and constructed to:
1. incorporate allowance for increased flood risk and tidal inundation through
pipework as a result of cilmate change and sea level rise;
2. ensure the development is adequately drained; and
3. ensure stormwater is managed and lawfully discharged without altering
stormwater drainage characteristics external to the site.
The concrete spoon drains proposed as the drainage infrastructure for the development,
will provide the batter slope protection required by the geotechnical slope stability
assessment to ensure water does not infiltrate into the batters. The spoon drains have
been sized based on the 1% AEP storm event, allowing a climate change increase of 20%
to the BoM IFD rainfall intensities for the site with the details of these calculations
attached. An assumed 20% impervious area has been taken into account in sizing the
lower earthworks pad to allow for any future development of this area
Finished surfaces are to be graded locally towards the drainage lines so that run-off from
the development will be collected in the drainage infrastructure. Minimum slopes of 1%
are proposed for the drains to ensure the site will be free draining, and also achieving the
required capacity for the major storm event.
The proposed point of discharge within the subject site is through a rock energy
dissipator falling towards of an existing drainage gully. The drainage gully is the eventual
point of capture of pre-development flows, so discharging to this location is considered to
maintain the existing flow paths from the site. The energy dissipator is located
approximately 30m from the adjacent property boundary and has been sized to prevent
erosion or scour of the gully and disperse concentrated flows so that when run-off crosses
the property boundary it will be sufficiently similar to pre-existing conditions that any
impacts to drainage characteristics external to the site are expected to be minimal.
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Page 4
PO5
Stormwater drainage infrastructure is aligned to avoid crossing waterways,
wetlands, drainage lines and ecological important areas, or where it is
demonstrated this is unavoidable, disturbed areas are reinstated and revegetated
upon completion of works.
PO6
Development is located, designed, constructed and operated to protect and
enhance environmental values and water quality of waterways, wetlands, lakes,
ground waters and drainage systems.
The drainage infrastructure proposed for the development does not cross waters ways,
wetlands, drainage lines and ecologically important areas. Drainage characteristics
downstream of the proposed development will be sufficiently similar to pre-development
conditions as described above, with the proposed outlet for the development into a gully
to which existing flows currently are collected. Additionally, disturbed areas arising from
the earthworks are to be stabilised with grass seeding after construction to minimise
sediment losses from the proposed development and maintain the water quality of the
downstream receiving water.
The environmental values and water quality of the receiving waters will be maintained
through the provision of erosion and sediment controls during construction in accordance
with the Erosion and Sediment Control Plan submitted with the application. Post
construction, stabilising of disturbed areas to minimise any risk of ongoing water quality
impacts from the earthworks.
PO10
Development prevents increased bed and bank erosion and sedimentation in
receiving waterways by avoiding changes in low rate, peak flow run-off and flow
duration.
An assessment of the estimated peak flows from the pre-development area and from the
earthworks pad was carried out to determine the impacts arising to peak flows for
different storm events using the rational method to provide an indication of the scale of
the change. A summary of the comparison is provided below – refer to the attached
calculations for further detail.
Qy (m3/s) - Pre-developed Qy (m3/s) - Earthworks Change (L/s) % Change
0.0331 0.0346 1.5889 0.0481
0.0399 0.0416 1.7136 0.0430
0.0602 0.0628 2.5536 0.0424
0.0740 0.0777 3.6587 0.0494
0.0891 0.0929 3.8416 0.0431
0.1129 0.1176 4.7227 0.0418
0.1301 0.1353 5.1968 0.0399
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Page 5
It was found that run-off stormwater peak and low rate storm flows resulting from the
earthworks are altered by less than 5%, which is considered an insignificant increase in
potential to increase bed or bank erosion or sedimentation in receiving waterways. The
provision of energy dissipating outlets to reduce flow velocity and disperse concentrated
flows will further reduce the potential of this increase having negative impacts to the
downstream waterways.
PO13
Development is designed and constructed to maintain surface and ground water
balances that sustain the environmental values of water dependent ecosystems,
including downstream aquatic, riparian, wetland and terrestrial ecosystems.
No attenuation or capture surface run-off is proposed, with all run-off from upstream
catchments and the proposed development areas discharge into the drainage gully to
which they would fall in the absence of the development. A geotechnical investigation
carried out by Morrison Geotechnics of the proposed development area did not identify
evidence of groundwater within boreholes taken from the development area, so it is not
considered likely that the proposed development will impact upon the surface and
ground water balances in a way that would negatively impact environmental values of
downstream ecosystems.
4. If the survey plan indicates that the works extend beyond the property
boundary provide plans for the works to be undertaken to relocate the
earthworks to be within the subject site.
A note on the design plan has been added indicating that earthworks extending across
the boundary are to be removed and reinstated to pre-development conditions. The run-
off that was being channelled to this area requiring a table drain at the base of the batter
slope is now conveyed to the north to ensure it is discharged clear of the boundary so
there are no issues with the removal of this small section of earthworks.
5. Provide comment on which is the preferred construction alternative and
provide amended plans prepared by a suitably qualified person which clearly
indicate the full extent of works required.
The batters for the development will be altered in line with the geotechnical
recommendations consisting of:
• Benching the cut batter where batter height exceeds 4m with maximum slope of
38º
• Flattening the fill batter to a maximum of 2.5H:1V
Please refer to the attached plan which provides the updated earthwork extents required
to comply with these design constraints.
P +61 7 5211 1003 A 37 Mary St, Noosaville Qld 4566 E [email protected] recorconsulting.com
Page 6
We believe the revised design as per the attached plans and as described in this letter
addresses the requirements of the RFI, however should further information be required
please contact this office.
Yours faithfully,
RECOR Pty Ltd
Authored By Reviewed By
SIGNATURE SIGNATURE
Benjamin Parry Nathan Wagstaff
Civil Engineer Manager
BEng (Hons) MIEAust BEng (Hons) MIEAust CPEng NER (Civil, Structural) RPEQ
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Page 7
Attachment A
Design Plan
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Page 8
OP WORKS
NOT FOR CONSTRUCTION
UPSTREAM SPOON DRAIN (600mm WIDE)
134
2H:1V MAX BATTER VANTAGE VSPOON DRAIN
2m MIN OR EQUIVALENT
38
2M WIDE BENCH
°M
PIPED STORMWATER
ANGULAR ROCK ENERGY DISSIPATOR AT OUTLET
AX
CROSSING
MEAN DIAMETER (D50) 200mm 9m 450mm PIPED CROSSING
38
1.8m L x 1.2m W x 0.32m D WITH CONCRETE HEADWALL 1m UPSTREAM SPOON DRAIN (450mm WIDE)
°M
AND ENDWALL AT 2% SLOPE
AX
22 ROCK ENERGY DISSIPATOR
°M
AX
132
134
136
DATUM RL 127.000
134 AS CON BATTER EXTENTS
67m Ø450mm VANTAGE CONCRETE
VSPOON DRAIN (OR EQUIVALENT)
AT 1% SLOPE
DESIGN BATTER EXTENTS
34 1
DRAINAGE DIRECTION
138.084
138.077
138.063
134.086
134.541
134.528
134.459
134.412
134.746
133.698
130.000
DESIGN
0
A
13
143.531
139.584
139.095
138.075
134.086
134.541
134.538
134.463
134.412
134.407
134.387
130.000
129.868
129.695
SURVEY (AS CON)
13
0
CHAINAGE
11.409
16.709
18.027
36.676
37.401
49.173
51.363
9.325
10
20
30
40
50
0
A-A - LONGITUDINAL SECTION
136 136
A1 HORZ SCALE 1:500
135.0
A1 VERT SCALE 1:250
128
138 PAD STORMWATER CATCHMENT UPSTREAM STORMWATER CATCHMENT
AREA: 0.16Ha AREA: 0.65Ha
Fi (Assumed): 20.0% Fi: 0.0%
tc (Mannings eqn): 6 Min tc (Friends eqn): 16 Min
Itc (1 IN 100): 302mm/hr Itc (1 IN 100): 205mm/hr
RATIONAL METHOD RATIONAL METHOD
140.0
1hrI10: 70.2mm/hr 1hrI10: 70.2mm/hr
C10: 0.74 C10: 0.70
13
Fy: 1.2 Fy: 1.2
0
Climate factor: 1.2 Climate factor: 1.2
130
Qy = 1/360 * 0.16 * (1.2*0.74) * 302*1.2 Qy = 1/360 * 0.65 * (1.2*0.70) * 205 *1.2
14
= 0.143m³/s = 0.373m³/s
4
2
13
SPOON DRAIN CAPACITY (CIRCULAR)- Mannings SPOON DRAIN CAPACITY (CIRCULAR)- Mannings
VANTAGE VSPOON OR EQUIVALENT VANTAGE VSPOON OR EQUIVALENT
Ø: 0.45m Ø: 0.6m
132
A
r: 0.225m r: 0.3m
14 n: 0.013 n: 0.013
4 Sf : 0.01 Sf : 0.015 DO NOT SCALE, IF IN DOUBT ASK!
Area of flow: 0.08m² Area of flow: 0.141m²
134 P: 0.707m P: 0.942m
R: 0.113m
134
R: 0.15m
5.0 13 Qmax: V*A Qmax: V*A
V: (1/n)*R^2/3*S^1/2 V: (1/n)*R^2/3*S^1/2
MAX FLOW DEPTH
V: 1.79m/s V: 2.66m/s
136 14 Qmax: 0.143m³/s Qmax: 0.376m³/s
6 Qmax >= Qy : TRUE Qmax >= Qy : TRUE
TREE IMPACTED BY BATTER TO
BE REMOVED OR RELOCATED STORMWATER CATCHMENT ASSESSMENT - SPOON DRAIN SIZING A 04/02/22 ISSUE FOR OP WORKS BP
138 CLEAR OF EARTHWORKS DIAMETER Rev Date Description By Chk
13 BASED ON SEMI-CIRCULAR CONCRETE PIPE SPOON DRAIN
8 NOMINALLY VANTAGE VSPOONDRAIN OR APPROVED EQUIVALENT
140 EARTHWORK NOTES
14
1. CONTRACTOR IS TO LOCATE ANY UNDERGROUND SERVICES WITHIN THE VICINITY AND NOTIFY RECOR OF ANY CONFLICTS.
2. ALL EARTHWORKS ARE TO BE IN ACCORDANCE WITH THE REQUIREMENTS OF "GEOTECHNICAL INVESTIGATION GLOBAL STABILITY
2
14
0 ASSESSMENT" DATED NOVEMBER 2021 BY MORRISON GEOTECHNIC. [email protected]
3. UPSTREAM CUT BATTER TO BE MAXIMUM 38° SLOPE TO A MAXIMUM 4m HEIGHT WITH 2M BENCH AND UPPER BATTER AT 38° MAXIMUM SLOPE 37 MARY ST NOOSAVILLE, QLD
REMOVE EARTHWORKS AND 77m Ø600mm VANTAGE CONCRETE TO MAXIMUM HEIGHT OF 3.5M. 07 5211 1003
REINSTATE TO EXISTING WHERE VSPOON DRAIN (OR EQUIVALENT) 4. DOWNSTREAM FILL BATTER TO BE MAXIMUM 2.5H:1V SLOPE Client
14
EARTHWORKS HAVE EXTENEDED MIN 1.5% SLOPE 5. FOLLOWING STRIPPING AND EXCAVATION OF PAD TO DESIGN LEVELS, PROOF ROLL TO IDENTIFY ANY SOFT SPOTS. SOFT SPOTS TO BE GEOFF HUSSIN
2
BEYOND PROPERTY BOUNDARY
EXCAVATED AND REPLACED WITH SELECT FILL. Project Name
6. ALL FILL TO BE COMPACTED AT +1-2% OPTIMUM MOISTURE CONTENT FOR STANDARD COMPACTION, AND FILL PLACED IN LAYERS MAXIMUM 36 TUNBA COURT
COOROY MOUNTAIN
150mm TO 200mm THICK (LOOSER THICKNESS) AND COMPACTED TO ACHIEVE DRY DENSITY RATIO OF MINIMUM 95% MAX DRY DENSITY
7. TEMPORARY OPEN SWALES AND DIVERSION DRAINS TO BE PLACED UPSTREAM OF EARTHWORKS DURING CONSTRUCTION TO PROTECT
14
EXCAVATION FROM SURFACE RUN-OFF.
4
Title
8. GRADE FINISHED SURFACES LOCALLY TOWARDS THE DRAINAGE LINE TO ENSURE FINISHED SURFACE IS FREE DRAINING AND WITHOUT BULK EARTHWORKS PLAN
AREAS SUBJECT TO PONDING.
9. VANTAGE VSPOON DRAINS (OR APPROVED EQUIVALENT) ARE TO BE INSTALLED IN ACCORDANCE WITH MANUFACTURERS REQUIREMENTS
AND SPECIFICATIONS.
14
10. CONCRETE HEADWALLS AND PIPES ARE TO BE INSTALLED IN ACCORDANCE WITH MANUFACTURERS REQUIREMENTS AND SPECIFICATIONS.
6
11. STORMWATER TO DISCHARGE THROUGH ROCKY ENERGY DISSIPATOR COMPRISED OF 320mm THICKNESS OF ANGULAR ROCK, WITH MEAN Project No. Discipline Status
DIAMETER OF 200mm TO PREVENT EROSION AND SCOUR AT OUTLETS. 20220004 CIVIL PRELIMINARY
12. EROSION AND SEDIMENT CONTROLS ARE TO BE IMPLEMENTED IN ACCORDANCE WITH THE EROSION AND SEDIMENT CONTROL PLAN Designed By Drawn By Scale
1:400
PREPARED BY AUSSIE ENVIRONMENTAL. BRP BRP (at A3)
13. ALL EXPOSED SURFACES ARE TO BE STABILISED WITH GRASS SEEDING OR TURFING AS SOON AS PRACTICABLE FOLLOWING COMPLETION OF Drawing No. Revision
EARTHWORKS. C30 A
Page 9
Attachment B
Stormwater Assessment
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Page 10
Rational Method Calculations
Project number: 20220004 Calculations: B. Parry
Street Address: 36 Tunba Ct
Locality: Cooroy Mountain, Noosa Shire Council Date: 8/02/2022
Pre-post earthworks run-off conditions
Pre-development Earthworks Pad
2
Impervious Surface 0 m
2
Permeable Area 1600 m
Total Site Area: 1600 m2
Time of Concentration
Time of Concentration
Sheet flow (Friends Eqn.)
Length 47 m Standard Inlet time 5 mins
Horton's n 0.04 Densely grassed
Fall over distance 14.5 m Pipe Flow
Slope 30.9 % Flow distance 66.00 m
Time 7.8 mins Slope 1 %
Pipe Diameter 0.45 m
Tc 8.0 mins Flow velocity (Mannings eqn.) 1.79 m/s
Time 0.61 mins
Time 6.0 mins
Rational Method Calculations
Area (Ha.) 0.160 Ha. Area (Ha.) 0.160 Ha.
fi 0.000 fi 0.000
1 1
I10 70.2 mm/hr I10 70.2 mm/hr
C10 0.70 C10 0.70
AEP Fy Cy Iy (2100) Qy (m3/s) AEP Fy Cy Iy (2100) Qy (m3/s)
63.2% AEP 0.8 0.560 132.82 0.0331 63.2% AEP 0.8 0.560 139.20 0.0346
50% AEP 0.85 0.595 150.72 0.0399 50% AEP 0.85 0.595 157.20 0.0416
20% AEP 0.95 0.665 203.76 0.0602 20% AEP 0.95 0.665 212.40 0.0628
10% AEP 1 0.700 237.84 0.0740 10% AEP 1 0.700 249.60 0.0777
5% AEP 1.05 0.735 272.64 0.0891 5% AEP 1.05 0.735 284.40 0.0929
2% AEP 1.15 0.805 315.60 0.1129 2% AEP 1.15 0.805 328.80 0.1176
1% AEP 1.2 0.840 348.48 0.1301 1% AEP 1.2 0.840 362.40 0.1353
Comparison Earthworks Vs Pre-development
Qy (m3/s) - Pre-developed Qy (m3/s) - Earthworks Change (L/s) % Change
0.0331 0.0346 1.5889 4.81
0.0399 0.0416 1.7136 4.30
0.0602 0.0628 2.5536 4.24
0.0740 0.0777 3.6587 4.94
0.0891 0.0929 3.8416 4.31
0.1129 0.1176 4.7227 4.18
0.1301 0.1353 5.1968 3.99
Page 11
Rational Method Calculations
Project number: 20220004 Calculations: B. Parry
Street Address: 36 Tunba Ct
Locality: Cooroy Mountain, Noosa Shire Council Date: 8/02/2022
Catchments Assessment for Spoon drain sizing
Upstream Catchment Earthworks area (assuming future development)
2 2
Impervious surface 0 m Impervious Surface (Rural - fi = 20%) 320 m
2 2
Permeable Area 6500 m Permeable Area 1280 m
Total Site Area: 6500 m2 Total Site Area: 1600 m2
Time of Concentration Time of Concentration
Existing Site Existing Site
Standard Inlet time 0 mins Standard Inlet time 5 mins
Sheet flow (Friends Eqn.) Pipe Flow
Length 133 m Flow distance 66.00 m
Horton's n 0.06 Densely grassed Slope 1 %
Fall over distance 49 m Pipe Diameter 0.45 m
Slope 36.8 % Flow velocity (Mannings eqn.) 1.79 m/s
Time 15.9 mins Time 0.61 mins
Tc 16.0 mins Time 6.0 mins
Rational Method - Peak Flow Calculation
Upstream Catchment Earthworks Pad (assuming future development)
Area (Ha.) 0.650 Ha. Area (Ha.) 0.160 Ha.
fi 0.000 fi 0.200
1 1
I10 70.2 mm/hr I10 70.2 mm/hr
C10 0.70 C10 0.74
AEP Fy Cy Iy (2100) Qy (m3/s) AEP Fy Cy Iy (2100) Qy (m3/s)
63.2% AEP 0.8 0.560 97.87 0.0990 63.2% AEP 0.8 0.592 139.20 0.0366
50% AEP 0.85 0.595 110.40 0.1186 50% AEP 0.85 0.629 157.20 0.0439
20% AEP 0.95 0.665 148.56 0.1784 20% AEP 0.95 0.703 212.40 0.0664
10% AEP 1 0.700 173.04 0.2187 10% AEP 1 0.740 249.60 0.0821
5% AEP 1.05 0.735 196.56 0.2609 5% AEP 1.05 0.777 284.40 0.0982
2% AEP 1.15 0.805 225.84 0.3283 2% AEP 1.15 0.851 328.80 0.1244
1% AEP 1.2 0.840 246.96 0.3746 1% AEP 1.2 0.888 362.40 0.1430
Channel Sizing
Using Manning's Eqn - V = R 2/3. Sf1/2/n
D 0.6 m D 0.45 m
r 0.3 m r 0.225 m
n 0.013 n 0.013
Sf (min) 0.015 m/m Sf (min) 0.010 m/m
A 0.141 m² A 0.080 m²
P 0.942 m P 0.707 m
R 0.150 m R 0.113 m
V 2.660 m/s V 1.793 m/s
QCapacity 0.376 >= 0.37 TRUE QCapacity 0.143 >= 0.143 TRUE
Page 12
IFDs Frequent and Infrequent Storm Events
Project number: 20220004
Street Address: 36 Tunba Ct
Locality: Cooroy Mountain, Noosa Shire Council
Source : http://www.bom.gov.au/water/designRainfalls/revised-ifd/
Location: Latitude:
-26.4248 [Nearest grid cell: 26.4125 (S)]
Longitude:
152.966 [Nearest grid cell: 152.9625 (E)]
Date obtained: 3/02/2022
Annual
Exceedance
Climate factor (1.2)
Probability
(AEP)
Duration 63.20% 50%# 20%* 10% 5% 2% 1% 63.20% 50%# 20%* 10% 5% 2% 1%
1 min 167 189 254 298 339 392 431 200.4 226.8 304.8 357.6 406.8 470.4 517.2
2 min 142 161 220 261 301 356 399 170.4 193.2 264 313.2 361.2 427.2 478.8
3 min 134 151 206 244 281 330 368 160.8 181.2 247.2 292.8 337.2 396 441.6
4 min 127 144 195 230 264 308 342 152.4 172.8 234 276 316.8 369.6 410.4
5 min 121 137 186 218 250 290 321 145.2 164.4 223.2 261.6 300 348 385.2
6 min 116 131 177 208 237 274 302 139.2 157.2 212.4 249.6 284.4 328.8 362.4
8 min 110.68 125.6 169.8 198.2 227.2 263 290.4 132.816 150.72 203.76 237.84 272.64 315.6 348.48
10 min 98.8 112 150 175 199 229 251 118.56 134.4 180 210 238.8 274.8 301.2
15 min 83.7 94.4 127 148 168 193 211 100.44 113.28 152.4 177.6 201.6 231.6 253.2
16 min 81.56 92 123.8 144.2 163.8 188.2 205.8 97.872 110.4 148.56 173.04 196.56 225.84 246.96
20 min 73 82.4 111 129 147 169 185 87.6 98.88 133.2 154.8 176.4 202.8 222
25 min 65.1 73.4 98.8 115 131 152 167 78.12 88.08 118.56 138 157.2 182.4 200.4
30 min 59 66.5 89.7 105 120 138 152 70.8 79.8 107.64 126 144 165.6 182.4
45 min 46.7 52.8 71.6 84.2 96.4 112 125 56.04 63.36 85.92 101.04 115.68 134.4 150
1 hour 39.3 44.5 60.7 71.7 82.4 96.7 108 47.16 53.4 72.84 86.04 98.88 116.04 129.6
1.5 hour 30.7 34.8 48 57 66 78 87.3 36.84 41.76 57.6 68.4 79.2 93.6 104.76
2 hour 25.7 29.3 40.6 48.5 56.4 67 75.2 30.84 35.16 48.72 58.2 67.68 80.4 90.24
3 hour 20 22.9 32.2 38.7 45.3 54.1 61.1 24 27.48 38.64 46.44 54.36 64.92 73.32
4.5 hour 15.7 18 25.7 31.1 36.5 43.9 49.7 18.84 21.6 30.84 37.32 43.8 52.68 59.64
6 hour 13.2 15.2 21.9 26.6 31.4 37.8 43 15.84 18.24 26.28 31.92 37.68 45.36 51.6
9 hour 10.3 12 17.5 21.4 25.3 30.7 35 12.36 14.4 21 25.68 30.36 36.84 42
12 hour 8.69 10.1 14.9 18.3 21.8 26.5 30.2 10.428 12.12 17.88 21.96 26.16 31.8 36.24
18 hour 6.77 7.95 11.8 14.6 17.5 21.3 24.4 8.124 9.54 14.16 17.52 21 25.56 29.28
24 hour 5.64 6.64 9.94 12.3 14.8 18.2 20.9 6.768 7.968 11.928 14.76 17.76 21.84 25.08
30 hour 4.87 5.74 8.64 10.8 13 16 18.5 5.844 6.888 10.368 12.96 15.6 19.2 22.2
36 hour 4.31 5.08 7.68 9.6 11.6 14.4 16.6 5.172 6.096 9.216 11.52 13.92 17.28 19.92
48 hour 3.52 4.16 6.32 7.93 9.64 12 13.9 4.224 4.992 7.584 9.516 11.568 14.4 16.68
72 hour 2.62 3.09 4.71 5.94 7.26 9.13 10.7 3.144 3.708 5.652 7.128 8.712 10.956 12.84
96 hour 2.1 2.48 3.77 4.77 5.86 7.38 8.66 2.52 2.976 4.524 5.724 7.032 8.856 10.392
120 hour 1.77 2.08 3.16 4 4.91 6.2 7.28 2.124 2.496 3.792 4.8 5.892 7.44 8.736
144 hour 1.54 1.8 2.73 3.45 4.23 5.33 6.25 1.848 2.16 3.276 4.14 5.076 6.396 7.5
168 hour 1.37 1.6 2.42 3.04 3.72 4.67 5.46 1.644 1.92 2.904 3.648 4.464 5.604 6.552
[OCR of page images]
iebs Frequent and infrequent Storm Events we
Projet number" 20220008 ae
street Address: 36 Tunba ct As
Locality Cooroy Mountain, Noosa Shire Council
Source Tittpi//www.bom.gov.au/water/designRainfalls/revised 1d),
Location: Latitude:
-26.4248 [Nearest grid cell: 26.4125 (S)]
Longitude
152.966 [Nearest grid cell: 152.9625 (E)]
Date obtained: 3/02/2022
Annual
Exceedance
Probability
Climate factor (1.2)
63.20% 63.20%
[10 min
115 min
[16 min
[20 min
[25 min
[30 min
[45 min
[1 hour
1.5 hour
2 hour
[3 hour
4.5 hour
[6 hour
[9 hour
112 hour
[18 hour
[24 hour
'30 hour
[36 hour
[48 hour
[72 hour
[96 hour
1120 hour
[144 hour
[168 hour