Original source · versioned page text
Appendix E - Integrated Water Management Plan
Attached to the e-mail Multiple Housing Type 3 Retirement & Special Needs (48 units) - MCU18/0009.
Plans and drawings: the text below has words only, no drawings.
Original PDF page 1, section 1. The text section number identifies this passage in the reader.
PROPOSED CARTWRIGHT VILLAGE EXTENSION -
CARRAMAR, NOOSACARE
INTEGRATED WATER MANAGEMENT PLAN
VERSION 0
FOR
NOOSA COUNCIL
LOT 2 on RP177554
186 COOROY NOOSA ROAD,
TEWANTIN
JANUARY 2018
SMH GT
9.5
9.5 LI
10 .0
10 . 0
10 . 0
bridge LI
LI
garden
LI
Villa No6
fence line
8. 0
garden
FFL 10.50
Villa No5
concrete path
FFL 10.50
ROOF AREA = 530m2
ROOF AREA = 530m2
building
Cartwright North
line
garden
LI 5
Existing 16 Residents Rooms 7.
FFL 10.35
9 .0
7.0
GT
concrete path
building line
tank
250pvc
Villa No4
RP177554
8 .5
FFL 10.50
SV
ROOF AREA = 561m2
fence line
Cartwright South
Existing 16 Residents Rooms
6 .5
FFL 10.35
garden
6 .5
SW
cu
rre
SW
nt
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ate
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TT*S10
TT*S10
ire fen
ce
7 .0
Villa No3
FFL 10.50
ROOF AREA = 561m2
gate
LI
0 LI Northeast Elevation
.0 1
FFL 405.000
ROOF AREA = 336m2
gully
SV
SW
7.5
Landscaped Podium
LI
TE
EMH FLAG
1
.5
0
LI 9. 0
7 .57.5
894
MA*S16
Villa No2
FFL 11.50
ROOF AREA = 530m2
5
0.
Villa No1
0
0.
1 1 FFL 11.50
ROOF AREA = 478m2 Q10 flood line
Landscaped Podium
identifing number
flagged trees with
8. 0
Q1
00
flo
od
lin
e
5
8.
Callaghan & Toth
Civil, Environmental & COOROY - NOO
SA ROAD
Hydraulic Engineers
SITE DETAILS
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Full text of sections 2 to 49 (of 53)
Section 2
Callaghan & Toth
DOCUMENT HISTORY
Document Reference: No: 1714 IWMP.doc
Project Manager: Peter Middap
Author: Lex Toth NPER3 (ENV) (CIVIL) RPEQ 6069 CPESC
Reviewer: Jane Davissen BE (ENV)
Client: Noosa Care Inc.
Contact Person: Megan D’Elton
DISTRIBUTION LIST
POSITION ON
NAME ORGANIZATION MANAGEMENT TEAM REVISION REVISION REVISION
0 1 2
Peter Middap Middap Architects Project Manager 1
Megan D’Elton Noosa Care Inc. Client 1
Lex Toth Callaghan & Toth Author 1
Noosa Council Assessment Officer 1
REVISION LIST
REVISION DATE DISTRIBUTED ISSUED BY CHECKED BY
0 10th January 2018 LT JD
The information contained in this report is confidential and proprietary to Callaghan and Toth. It may
only be used by the person to whom it is provided, for the stated purpose for which it is provided, and
must not be imparted to any third person without the prior written approval of Callaghan and Toth.
Callaghan and Toth reserve all legal rights and remedies in relation to infringement of its rights in
respect of its confidential information.
©Callaghan & Toth
2018
2
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 3
Callaghan & Toth
CONTENTS
1. SUMMARY............................................................................................................................................5
2. INTRODUCTION ..................................................................................................................................5
3. DESCRIPTION .....................................................................................................................................7
3.1 Proposed Works ............................................................................................................................7
4. WATER QUALITY MANAGEMENT PLAN ............................................................................................9
4.1 Proposed On-Site Stormwater Treatment Process ........................................................................9
4.2 MUSIC Model ................................................................................................................................9
4.2.1 Source Nodes ........................................................................................................................9
4.2.2 Treatment Nodes .................................................................................................................10
4.2.3 Rainfall Data ........................................................................................................................12
4.3 MUSIC Modelling Results ............................................................................................................12
4.3.1 Water Quality Objectives .....................................................................................................12
4.3.2 Assessment of Results ........................................................................................................13
5 WATER CYCLE MANAGEMENT PLAN .............................................................................................14
6 STORMWATER DETENTION AND FLOODING REPORTS ..............................................................16
6.1 Existing Conditions ......................................................................................................................16
6.2 Proposed Drainage System .........................................................................................................16
6.3 Filling Within the Flood Plain .......................................................................................................16
7 CONCLUSIONS & RECOMMENDATIONS ........................................................................................17
APPENDIX A - MUSIC Results ......................................................................................................... A
APPENDIX B - Preliminary Design of Stormwater Detention Volume – BSM Report......................... B
3
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 4
Callaghan & Toth
LIST OF REFERENCES
1. EN HEALTH (2004) Guidance on the Use of Rain Water Tanks.
2. Engineers Australia (2006) Australian Runoff Quality. Australian Runoff Quality
Guidelines.
3. Healthy Waterways (2006) Water Sensitive Urban Design Technical Design Guidelines
for South East Queensland
4. Queensland Development Code Part 4.3 (Oct 2008) Alternative Water Sources.
5. Water by Design, MUSIC Modelling Guidelines for South East Queensland – Version 1
(December 2010)
6. Water by Design, Deemed to Comply Solutions – Stormwater Quality Management
(South East Queensland), May 2010
7. Wong, T., Breen, P. & Lloyd, S. (2000) Water Sensitive Road Design – Design Options
for Improving Stormwater Quality of Road Runoff. CRC for Catchment Hydrology
Technical Report No 00/1.
LIST OF FIGURES
Figure 1.1 Site Location Plan……………………………………………………… 6
Plan No. 1714-01 Preliminary Integrated Water Management Layout Plan 2...............8
Figure 4.1 MUSIC Model for the Proposed Development……………………… 11
Figure 4.2 Typical Rainwater Tank………………………………………............. 15
LIST OF TABLES
Table 4.1 MUSIC Catchment Areas……………………………………………….10
Table 4.2 Comparison of Load Reductions……………………………………….12
4
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 5
Callaghan & Toth
1. SUMMARY
The key points of this investigation are as follows:
1. Roof water runoff is to be collected in six rainwater tanks and recycled to provide
potable water to toilets and hose cocks for gardens.
2. Runoff from new access roads, car parks and landscaped areas around the buildings is
to be cleaned of nutrients and gross pollutants via five Biopods, GPT and then released
to existing outlets into adjacent vegetation.
3. The increase in pollutant loads due to the increase in impervious areas is to be
attenuated.
4. Water saving devices for new fixtures are required.
5. The increase in runoff is attenuated by three underground detention/infiltration storage
systems.
2. INTRODUCTION
This report was written as part of an MCU application for Noosa Council, and is in accordance
with:
1. Water Sensitive Design Code in the Noosa Plan
2. The latest Water Sensitive Urban Design Technical Design Guidelines for South East
Queensland, published by Health Waterways
The site subject to this report is Lot 2 RP177554 at Cooroy Noosa Road, Tewantin (refer Site
Location Plan Figure 1.1). The current uses on site include landscaped areas and adjacent
bushland.
The Integrated Water Management Plan relates to new Villas, access roads, carparks, café,
pathways and landscaping for the proposed Cartwright Village Extension at Carramar, Cooroy
Noosa Road, Tewantin.
There is a total new roof area of 3526m2 for the Villas and café that flows to seven rainwater
tanks, and a total area of access roads and car parks, pathways and landscaped area of
4524m2 that flows to five Biopods.
In order to receive planning approval from Noosa Council, this site must demonstrate that it
complies with Council’s Water Sensitive Design Code and that the storm water runoff will not
change the surrounding hydrology. Biopods infiltration and above ground roof water tanks are
required for the site. These devices will enable the water quality objectives to be achieved.
Water reuse and water use minimisation are in accordance with the guidelines.
The Model for Urban Stormwater Improvement Conceptualization (MUSIC) has been used to
assess the suitability of various treatment devices and to model existing and predicted pollution
export loads and concentrations.
The rainwater tanks have been sized in accordance with the Queensland Development Code
MP4.3 for toilet use.
5
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 6
Callaghan & Toth
Civil, Environmental &
Hydraulic Engineers
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Callaghan & Toth PROPOSED CARTWRIGHT VILLAGE SITE LOCATION PLAN
Civil, Environmental & EXTENSION — CARRAMAR
Hydraulic Engi !
"Yi" Sestine desk tea | 186 COOROY NOOSA ROAD,
P.0. Box 2305 TEWANTIN
i NOOSA’ HEADS 4567
— Ph: 54749081 Fax: 54749041 Fig ure 1.1
www.callaghanandtoth.com.au
Source: http://whereis.com.au/ Scale:NTS
Section 7
Callaghan & Toth
3. DESCRIPTION
The site is bounded by residential properties to the north and west, park reserve to the east and
Cooroy-Noosa Road to the south. The site consists of an aged care facility with an existing
carpark, access roads, pathways and an area of native bushland.
This site is subject to the ponding of floodwaters. Cardno undertook a flood study in 2006 for
Noosa Care. This was amended by Cardno and is presented as “Flood Study – Noosa Care –
Carramar (WE17064) dated 24 July 2017. This amended flood study determined the location of
the Q100 year ARI flood line which is generally between the RL 8.0 and RL 8.5m contour lines.
3.1 Proposed Works
The proposed extension of the Cartwright Village will include the addition of new buildings,
carpark and associated landscaping and paths as follows:
▪ Administration/Café,
▪ 6 x Villas (8 bedrooms),
▪ Extend the existing carpark,
▪ Landscaped podium near Villa 1 and 2, and
▪ Landscaping and pathways.
As a result of these works, stormwater drainage and treatment devices are required to drain the
site, attenuate flows and treat stormwater runoff to acceptable levels.
Plan 1714-01 A shows the catchments identified onsite and general locations of proposed
treatment devices.
7
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 8
Callaghan & Toth
Civil, Environmental &
SMH GT
Hydraulic Engineers
9 .5
9. 5 LI
10 . 0
10 . 0
10 . 0
bridge LI
LI
garden
LI
Villa No6
fence line
8 .0
garden
FFL 10.50
Villa No5
concrete path
FFL 10.50
ROOF AREA = 530m2
ROOF AREA = 530m2
A
buildin
g
Cartwright North
line
garden
LI 5
Existing 16 Residents Rooms 7.
FFL 10.35
B5
9.0
7. 0
GT
concrete path
CATCHMENTS
building line
tank
250p
Villa No4
A - 0.313ha
RP177554
vc
8 .5
FFL 10.50
SV
ROOF AREA = 561m2
fence line
Cartwright South
Existing 16 Residents Rooms
B - 0.346ha
6 .5
FFL 10.35
C - 0.056ha
garden
D - 0.038ha
E - 0.021ha
6.5
SW
F - 0.037ha
cu
rre
SW
ts n
an t
TOTAL = 0.811ha
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nk
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TT*S10
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nce
7.0
B Villa No3
FFL 10.50
ROOF AREA = 561m2
BIO PODS
B1 - 10m²
gate
B2 - 10m²
LI
B3 - 10m²
B4 - 20m²
LI Northeast Elevation
B4 B5 - 20m²
B3
0
1
.0
FFL 405.000
ROOF AREA = 336m2
gully
SV
SW
7. 5
Landscaped Podium
LI
TE
D LEGEND:
EMH FLAG
1
.5
0
LI 9.0
7. 5 7. 5
894
Villa No2 MA*S16
CATCHMENTS
B1
FFL 11.50
ROOF AREA = 530m2
5
0.
Villa No1
0
E B2
0.
1 1 FFL 11.50
ROOF AREA = 478m2 BIO PODS
F
Q10 flood line
Landscaped Podium
identifing number
flagged trees with
B2
8. 0
Q1
00
flo
od
lin
e
RAINWATER TANK 14,000L EACH
5
8.
DETENTION TANK
OSA ROAD
COOROY - NO ROOF AREA
Section 9
Callaghan & Toth
4. WATER QUALITY MANAGEMENT PLAN
4.1 Proposed On-Site Stormwater Treatment Process
The developed site was divided into MUSIC model sub-catchments as shown on Plan No.
1714-01. The proposed treatment train for the development site is also illustrated on Plan No.
1714-01 and listed below:
1. The Biopods – small bioretention basins will treat the stormwater runoff from the access
roads, car parks, landscaped areas and rainwater tank overflows, landscaped podium, etc.
The treated runoff will then be directed to an existing storm water pipe within the property.
The bio-retention component will remove the nutrients and retard flow.
2. Rainwater Tanks will be required to collect water from the new roofs. Seven tanks all of
14,000 litre capacity will be above ground and have potable top-up supply when 80% empty
with an overflow pipe discharging to the underground detention system. The tank capacity is
to be adequate for the supply of toilets and some landscape watering.
4.2 MUSIC Model
4.2.1 Source Nodes
Catchment areas of source nodes within the proposed development have been identified as
sub-catchments such as roofs, carparks, road and verge areas. MUSIC allows for the
characteristics of these source nodes to be amended to ensure that accurate pollution
generation and hydraulic characteristics are used to generate stormwater runoff within the
model. Table 4.1 below details the sub-catchments used in the MUSIC model, land use,
percent imperviousness and area of each sub-catchment. The MUSIC Modelling Guidelines for
South-East Queensland – Version 1 December 2010 have been used to set levels of
imperviousness. The site has been related to a “Commercial” land use and pollutant export
parameters detailed in the Guidelines for this land use have been used for each node.
9
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 10
Callaghan & Toth
TABLE 4.1 MUSIC CATCHMENT AREAS (DEVELOPED)
Catchment Land Use Music Area (ha)
Impervious
CATCHMENT A
Roof Areas – Villas 4, 5, and 6 Urban Residential 100% 0.162
Northern Pathways / Landscaped areas Urban Residential 35% 0.151
CATCHMENT B
Southern Pathways / landscaped areas Urban Residential 35% 0.163
Landscaped Podium Urban Residential 75% 0.049
Roof Areas – Villas 1, 2, and Cafe 100% 0.134
Urban Residential
CATCHMENT C – Villa 3 Urban Residential 100% 0.056
CATCHMENT E - Existing driveways / 3 carparks Urban Residential 90% 0.021
CATCHMENT D & F - Exposed Carpark Areas Urban Residential 90% 0.075
TOTAL 0.81ha
4.2.2 Treatment Nodes
The “MUSIC Modelling Guidelines for South East Queensland” Version 1.0 prepared by Water
by Design and dated December 2010 has been used to set the rainfall runoff parameters and
pollutant export parameters for the site.
The land use type used for this model was “Commercial” and the values in the guideline shown
in Table 3.7 and Table 3.8 of the guidelines have been used in this model. Figure 4.1 shows
the MUSIC Model layout for the site.
Bioretention Basins (Biopods) have been placed to treat flows from carparks, existing roads,
proposed villas and the tank overflows, landscaped areas, and pathways. To treat the new
areas, five biopods have been placed to catch flows draining from the listed areas. The
Biopods range in size from 10 to 20m2 dependent on catchment size. Each biopod has a filter
layer depth of 0.4m and an extended detention depth of 0.10m. The size and depth of these
systems has been designed in accordance with Water by Design guidelines. The bio-pods
drain to the unnamed waterway on site to the east of the proposed development.
Seven (7) Rainwater Tanks have been provided for the roof catchments as shown on Plan No
1714-01. The Reuse allowed is for:
1. Villas – toilets daily re-use – allow 1500 litres / pedestal in accordance with QDC.
2. Some watering of landscaping.
Sizing checks for the seven rainwater tanks is detailed in Section 5.0 below.
10
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 11
Callaghan & Toth
Civil, Environmental &
Hydraulic Engineers
[OCR of page images]
A_landscaped areas [M TCHMENT A_Villa4, 5 & &
e
‘3x 14,000 litre RWT
(CATCHMENT (C_Villa 3 [Mi
(CATCHMENT B.
Receiving Node - Tributary of Wooroi Ck
eG
CATCHMENT B_Cafe Roof [Mi rT
14, litre RV
Podium [Mi 8
& 14,000 litre RWT-
‘TCHMENTB_ Villa 1&2
Biopod 3.
(\TCHMENT D_Exposed Carpark Areas (eastern end) [M
Biopod 1
CATCHEMNT F-
CATCHMENT E_Existing driveway and 3 carparks [Mixed]
project
Callaghan & Toth | PROPOSED CARTWRIGHT VILLAGE MUSIC MODEL FOR
Civil, Environmental & | EXTENSION — CARRAMAR PROPOSED DEVELOPMENT
Hydraulic Engineers
8/41 Sunshine Beach Road 186 COOROY NOOSA ROAD,
woos ie 2305 TEWANTIN .
Ph: 54749081 Fax: 54749041 Fig ure 4.1
www.callaghanandtoth.com.au
Scale:NTS
Section 12
Callaghan & Toth
4.2.3 Rainfall Data
The meteorological data used for the MUSIC Model was the data for Cooroy from 01/01/73 –
31/12/82.
The mean Annual Rainfall for Cooroy 1973 – 1982 = 1600mm
The MUSIC Modelling Guidelines for South East Queensland – Version 1 December 2010
details that Cooroy data for 1973 to 1983 should be used.
4.3 MUSIC Modelling Results
The MUSIC modelling program has been used to investigate the performance of various
treatment options in the treatment train. MUSIC version 6.2.1 is the current version and capable
of incorporating rainwater re-use in the model. These features have been used in making
comparisons between different stormwater management systems for this report.
4.3.1 Water Quality Objectives
This model meets the pollution load reduction target as detailed in the State Planning Policy
2017 (Appendix 2: Table B). The following have been included in Appendix B.
• The treatment train effectiveness for the system.
• The MUSIC Version 6.2.1 Summary Report.
The information above indicates that the new Villas, Café and associated carpark and
landscaping with the proposed stormwater treatment train will achieve reductions in pollutant
loads as detailed in Table 4.2 below.
TABLE 4.2: COMPARISON OF LOAD REDUCTIONS
Parameter MUSIC POLLUTANT LOAD
REDUCTION REDUCTION
RESULT TARGETS
(Source: SPP 2017)
Flow 17%
Total Suspended Solids 79.8% 80%
Total Phosphorous 59.6% 60%
Total Nitrogen 52% 45%
Gross Pollutants >5mm 100% 90%
12
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 13
Callaghan & Toth
4.3.2 Assessment of Results
The developed site has been modelled as a series of commercial sub-catchments, which
incorporate Water Sensitive Urban Design (WSUD) treatment trains. Plan No 1714-01 shows
the proposed locations of the rainwater tanks; detention systems and biopods. The reductions
listed in Section 4.3.1 above generally comply with Council’s requirements.
The percentage reductions for Total Suspended Solids and Total Phosphorus are slightly below
the target figures, by 0.2% and 0.4% respectively. These amounts are considered within error
range and therefore, it is considered that the proposed stormwater treatment system is
sufficient to reduce the pollutants prior to exiting the site.
13
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 14
Callaghan & Toth
5 WATER CYCLE MANAGEMENT PLAN
This development has been designed to in accordance with the ‘Deemed to Comply Solutions –
Stormwater Quality Management (SEQ) May 2010’ and the Queensland Development Code
MP 4.3.
To this end, 100% of the new Villa’s and café roofs on the site will be connected to rainwater
tanks, therefore seven tanks will be provided. The tanks will each have a capacity of 14,000
litres, which is in excess of the complying solutions requirement.
The rainwater tanks will supply water for toilet flushing and hose cocks adjacent the building for
irrigation of adjacent landscaping, and tank sizing will be based on:
• Each villa contains 8 pedestals.
• Administration building / Café has 3 pedestals.
• The size of the landscaped areas of extension works that will be irrigated is 1,432m2.
The tanks sizing has been checked in accordance with the Queensland Development Code
MP4.3 per compliance with storage for toilet flushing and Water by Design Music Guidelines
Version 1 December 2010 for storage for irrigation of landscaping to Commercial sites.
Complying Solution 1:
Queensland Development Code MP4.3 per compliance with storage for toilet flushing details
that rainwater tanks have a minimum storage capacity of 1,500 litres per required pedestal and
any additional capacity as specified in Appendix B of the QDC. As such the following
calculations are offered:
MINIMUM STORAGE CAPACITY:
Per Villa: 8 pedestals x 1500L/pedestal (toilet) = 12,000L / villa
Admin / Café: 3 Pedestals x 1500L/ Pedestals (toilet) = 4,500L Admin
For landscaping the water by design guidelines specify:
Annual demand = irrigated area 1,432 m2 x 0.548m/year = 784.75KL/yr
Daily demand = Annual demand /365 = 2,150L/day
10 day demand = 2150L/day x10 days = 21,500L
Total Storage required on site for 10 day Supply = (12,000L x 6) + 4500L + 21,500L
= 98,000L
It is recommended that a minimum of 7 tanks, each with 14,000 litres of rainwater storage for
toilet flushing, and landscape irrigation be provided giving a total of 98,000 litres of storage.
14
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 15
Callaghan & Toth
Civil, Environmental &
Hydraulic Engineers
[OCR of page images]
SCREENED OVERFLOW PIPE
TO BIORETENTION BASIN
SUPPLY OFF TAKE
TO TOILET
FLUSHING COLD
WATER WASHING
MACHINE AND
LANDSCAPING
ROOFWATER DOWNPIPE
—_—
FIRST FLUSH DIVERSION
LO SYSTEM TO GARDEN BEDS
=
OC
20% VALVE SHUT OFF LEVEL
10% FLOAT SWITCH/VALVE ACTIVATION LEVEL
Callaghan & Toth
Civil, Environmental &
Hydraulic Engineers
8/41 Sunshine Beach Road
P.O. Box 2305
i NOOSA HEADS 4567
Ph: 54749081 Fax: 54749041
www.callaghanandtoth.com.au
project
PROPOSED CARTWRIGHT VILLAGE
EXTENSION — CARRAMAR
location
186 COOROY NOOSA ROAD,
TEWANTIN
TYPICAL RAINWATER TANK
Figure 4.2
Scale:NTS
Section 16
Callaghan & Toth
6 STORMWATER DETENTION AND FLOODING REPORTS
6.1 Existing Conditions
This site is subject to ponding of floodwaters from the Q100 year ARI flood levels. The habitable
floor areas of the new buildings and new carpark are above the Q100 year ARI flood levels.
6.2 Proposed Drainage System
The carpark surface level is proposed to be drained to an underground drainage system
capable of taking a Q5 flow. The overflow will discharge to the existing storm water drains and
surrounding grass verge.
The habitable minimum floor level for the proposed centre is to be set at RL10.05. The
minimum carpark level is RL9.53, which is not affected by the Q100 flood level.
Allowance has been made to collect the runoff from the proposed new buildings, carparks, and
hard stand areas. The roofwater is collected in above ground rainwater tanks and will be used
for toilet flushing and landscape irrigation. The overflow from roofs will be piped to underground
ECO AID detention cells which will attenuate the flow back to predevelopment levels. Outlets
from the ECO AID cells and field inlet pits in carpark and landscape. Runoff from patio and
landscape garden areas will be directed to the biopods which will then treat the water to remove
pollutants before releasing the stormwater into the existing gully riparian zone.
The Bioretention basin, rainwater tanks and infiltration/ detention basins have been modelled to
act as a detention basin. The storage size is sufficient to reduce the increase in runoff from the
additional hard stand area and buildings back to predevelopment levels as summarised in
preliminary design of stormwater detention volume Appendix C.
6.3 Filling Within the Flood Plain
Q10 and Q100 flood levels based on amended Cardno flood study is shown on Middap
Architectural plan 1717 DA-01 A.
Filling within some edges of the Q10 to Q100 flood levels is required for the purpose of safe
access to all buildings refer to Middap Architectural plan 1717 DA-04A.
These fill areas are to be offset by excavation of similar flood storage heights under the new
buildings. These excavations under buildings are shown on Middap Architectural plans 1717
DA06 – 07 A.
The flood consultant will be required to rerun the flood model incorporating these compensatory
excavated areas and fill areas at the Operational Works stage. Adjustments will be made as
necessary to the compensatory excavation areas to ensure that the flood levels remain at pre-
development levels.
16
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 17
Callaghan & Toth
7 CONCLUSIONS & RECOMMENDATIONS
The proposed development area can be treated by a treatment train consisting of rainwater
reuse tanks and biopods, which are capable of removing the nutrients and heavy metals.
The car parking and new building can be built to flood free levels in accordance with Council’s
requirements.
A system of detention tunnels (ECOAID) are able to attenuate the runoff concentrations back to
Pre-Development levels and so the development will not have an impact on the hydrology of the
receiving waters.
17
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 18
Callaghan & Toth
APPENDIX A - MUSIC Results
A
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 19
Source nodes
CATCHMENT CATCHMENT
CATCHMENT E_Existing CATCHMENT CATCHEMNT CATCHMENT D_Exposed
CATCHMENTB_Vill A_landscaped CATCHMENT CATCHMENT driveway and 3 CATCHMENT B_Landscaped F_Exposed B_landscaped Carpark Areas
Location a1&2 areas B_Cafe Roof A_Villa 4_ 5 & 6 carparks C_Villa 3 Podium Carpark Areas areas (eastern end)
ID 2 5 6 8 10 13 15 16 18 19
UrbanSourceNo UrbanSourceNo UrbanSourceNo UrbanSourceNo UrbanSourceNo UrbanSourceNo UrbanSourceNo UrbanSourceN UrbanSourceNo
Node Type UrbanSourceNode de de de de de de de ode de
Zoning Surface Type Mixed Mixed Mixed Mixed Mixed Mixed Mixed Mixed Mixed Mixed
Total Area (ha) 0.101 0.206 0.034 0.162 0.021 0.053 0.049 0.037 0.177 0.038
Area Impervious (ha) 0.101 0.072299474 0.034 0.162 0.018925036 0.053 0.036771851 0.033344111 0.062121392 0.034245304
Area Pervious (ha) 0 0.133700526 0 0 0.002074964 0 0.012228149 0.003655889 0.114878608 0.003754696
Field Capacity (mm) 200 200 200 200 200 200 200 200 200 200
Pervious Area Infiltration Capacity coefficient - a 211 211 211 211 211 211 211 211 211 211
Pervious Area Infiltration Capacity exponent - b 5 5 5 5 5 5 5 5 5 5
Impervious Area Rainfall Threshold (mm/day) 1 1 1 1 1 1 1 1 1 1
Pervious Area Soil Storage Capacity (mm) 500 500 500 500 500 500 500 500 500 500
Pervious Area Soil Initial Storage (% of Capacity) 10 10 10 10 10 10 10 10 10 10
Groundwater Initial Depth (mm) 50 50 50 50 50 50 50 50 50 50
Groundwater Daily Recharge Rate (%) 28 28 28 28 28 28 28 28 28 28
Groundwater Daily Baseflow Rate (%) 27 27 27 27 27 27 27 27 27 27
Groundwater Daily Deep Seepage Rate (%) 0 0 0 0 0 0 0 0 0 0
Stormflow Total Suspended Solids Mean (log mg/L) 1.3 2.18 1.3 1.3 2.43 1.3 -0.97 2.43 2.18 2.43
Stormflow Total Suspended Solids Standard Deviation (log mg/L) 0.39 0.39 0.39 0.39 0.39 0.39 0.31 0.39 0.39 0.39
Stormflow Total Suspended Solids Estimation Method Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic
Stormflow Total Suspended Solids Serial Correlation 0 0 0 0 0 0 0 0 0 0
Stormflow Total Phosphorus Mean (log mg/L) -0.89 -0.47 -0.89 -0.89 -0.3 -0.89 -0.3 -0.3 -0.47 -0.3
Stormflow Total Phosphorus Standard Deviation (log mg/L) 0.31 0.31 0.31 0.31 0.31 0.31 0.31 0.31 0.31 0.31
Stormflow Total Phosphorus Estimation Method Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic
Stormflow Total Phosphorus Serial Correlation 0 0 0 0 0 0 0 0 0 0
Stormflow Total Nitrogen Mean (log mg/L) 0.26 0.26 0.26 0.26 0.26 0.26 0.26 0.26 0.26 0.26
Stormflow Total Nitrogen Standard Deviation (log mg/L) 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23
Stormflow Total Nitrogen Estimation Method Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic
Stormflow Total Nitrogen Serial Correlation 0 0 0 0 0 0 0 0 0 0
Baseflow Total Suspended Solids Mean (log mg/L) 0 1 0 0 1 0 1 1 1 1
Baseflow Total Suspended Solids Standard Deviation (log mg/L) 0 0.34 0 0 0.34 0 0.34 0.34 0.34 0.34
Baseflow Total Suspended Solids Estimation Method Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic
Baseflow Total Suspended Solids Serial Correlation 0 0 0 0 0 0 0 0 0 0
Baseflow Total Phosphorus Mean (log mg/L) 0 -0.97 0 0 -0.97 0 -0.97 -0.97 -0.97 -0.97
Baseflow Total Phosphorus Standard Deviation (log mg/L) 0 0.31 0 0 0.31 0 0.31 0.31 0.31 0.31
Baseflow Total Phosphorus Estimation Method Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic
Baseflow Total Phosphorus Serial Correlation 0 0 0 0 0 0 0 0 0 0
Baseflow Total Nitrogen Mean (log mg/L) 0 0.2 0 0 0.2 0 0.2 0.2 0.2 0.2
Baseflow Total Nitrogen Standard Deviation (log mg/L) 0 0.2 0 0 0.2 0 0.2 0.2 0.2 0.2
Baseflow Total Nitrogen Estimation Method Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic Stochastic
Baseflow Total Nitrogen Serial Correlation 0 0 0 0 0 0 0 0 0 0
Flow based constituent generation - enabled Off Off Off Off Off Off Off Off Off Off
OUT - Mean Annual Flow (ML/yr) 1.43 1.74 0.483 2.3 0.28 0.753 0.588 0.493 1.5 0.506
OUT - TSS Mean Annual Load (kg/yr) 41.4 345 14.3 69.1 114 22.5 0.415 194 284 200
OUT - TP Mean Annual Load (kg/yr) 0.234 0.681 8.13E-02 0.381 0.181 0.125 0.366 0.314 0.581 0.325
OUT - TN Mean Annual Load (kg/yr) 3.01 3.57 1.01 4.85 0.588 1.58 1.22 1.02 3.05 1.07
OUT - Gross Pollutant Mean Annual Load (kg/yr) 34 39.1 11.5 54.6 6.73 17.9 14.4 11.9 33.6 12.2
Rain In (ML/yr) 1.56155 3.18493 0.525667 2.50465 0.324678 0.819423 0.757581 0.572051 2.73656 0.587512
ET Loss (ML/yr) 0.126615 1.45634 0.0426239 0.20309 0.0451166 0.0664425 0.171037 0.0794911 1.25132 0.0816393
Deep Seepage Loss (ML/yr) 0 0 0 0 0 0 0 0 0 0
Baseflow Out (ML/yr) 0 0.272525 0 0 0.00427413 0 0.0249323 0.00753054 0.23416 0.00773408
Section 20
Imp. Stormflow Out (ML/yr) 1.43493 1.02434 0.483044 2.30157 0.268516 0.752982 0.522115 0.4731 0.880137 0.485886
Perv. Stormflow Out (ML/yr) 0 0.446236 0 0 0.00699848 0 0.0408244 0.0123306 0.383416 0.0126639
Total Stormflow Out (ML/yr) 1.43493 1.47058 0.483044 2.30157 0.275514 0.752982 0.562939 0.48543 1.26355 0.49855
Total Outflow (ML/yr) 1.43493 1.7431 0.483044 2.30157 0.279788 0.752982 0.587871 0.492961 1.49771 0.506284
Change in Soil Storage (ML/yr) 0 -0.0145128 0 0 -0.000227638 0 -0.00132774 -0.00040099 -0.0124698 -0.000411887
TSS Baseflow Out (kg/yr) 0 3.6899 0 0 0.0579921 0 0.338134 0.101719 3.17224 0.104506
TSS Total Stormflow Out (kg/yr) 41.4081 341.401 14.2913 69.071 113.773 22.5125 0.0775146 193.968 281.154 199.806
TSS Total Outflow (kg/yr) 41.4081 345.091 14.2913 69.071 113.831 22.5125 0.415648 194.069 284.326 199.911
TP Baseflow Out (kg/yr) 0 0.0375639 0 0 0.000589139 0 0.00344196 0.00103992 0.0322962 0.00106591
TP Total Stormflow Out (kg/yr) 0.234185 0.643486 0.0813239 0.381384 0.180195 0.125463 0.362754 0.312915 0.548611 0.324353
TP Total Outflow (kg/yr) 0.234185 0.68105 0.0813239 0.381384 0.180784 0.125463 0.366196 0.313954 0.580908 0.325418
TN Baseflow Out (kg/yr) 0 0.47951 0 0 0.00754183 0 0.0439173 0.0132235 0.413663 0.0135993
TN Total Stormflow Out (kg/yr) 3.01389 3.0926 1.01001 4.84616 0.580875 1.57812 1.17353 1.01039 2.64116 1.0538
TN Total Outflow (kg/yr) 3.01389 3.57211 1.01001 4.84616 0.588417 1.57812 1.21745 1.02362 3.05483 1.0674
GP Total Outflow (kg/yr) 34.0252 40.2233 11.454 54.5751 6.75384 17.8548 14.4883 11.8996 34.5608 12.2212
No Imported Data Source nodes
USTM treatment nodes
Location 2 x 14_000 litre RWT Biopod 4 14_000 litre RWT
3 x 14_000 litre RWT Biopod 1 Biopod 5 14_000 litre RWT Biopod 2 Biopod 3
ID 3 4 7 9 11 12 14 17 20
Node Type RainWaterTankNodeBioRetentionNodeV4
RainWaterTankNode
RainWaterTankNode
BioRetentionNodeV4
BioRetentionNodeV4
RainWaterTankNode
BioRetentionNodeV4
BioRetentionNodeV4
Lo-flow bypass rate (cum/sec) 0 0 0 0 0 0 0 0 0
Hi-flow bypass rate (cum/sec) 100 100 100 100 100 100 100 100 100
Inlet pond volume 0 0 0 0
Area (sqm) 14 20 7 21 10 20 7 10 10
Initial Volume (m^3) 27.96 13.98 41.94 13.98
Extended detention depth (m) 0.01 0.3 0.01 0.01 0.2 0.3 0.01 0.2 0.2
Number of Rainwater tanks 2 1 3 1
Permanent Pool Volume (cubic metres) 27.96 13.98 41.94 13.98
Proportion vegetated 0 0 0 0
Equivalent Pipe Diameter (mm) 424 300 520 300
Overflow weir width (m) 10 0.2 10 10 2 0.2 10 2 2
Notional Detention Time (hrs) 9.28E-04 9.27E-04 9.26E-04 9.27E-04
Orifice Discharge Coefficient 0.6 0.6 0.6 0.6
Weir Coefficient 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7
Number of CSTR Cells 2 3 2 2 3 3 2 3 3
Total Suspended Solids - k (m/yr) 400 8000 400 400 8000 8000 400 8000 8000
Total Suspended Solids - C* (mg/L) 12 20 12 12 20 20 12 20 20
Total Suspended Solids - C** (mg/L) 12 12 12 12
Total Phosphorus - k (m/yr) 300 6000 300 300 6000 6000 300 6000 6000
Total Phosphorus - C* (mg/L) 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13
Total Phosphorus - C** (mg/L) 0.13 0.13 0.13 0.13
Total Nitrogen - k (m/yr) 40 500 40 40 500 500 40 500 500
Total Nitrogen - C* (mg/L) 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4
Total Nitrogen - C** (mg/L) 1.4 1.4 1.4 1.4
Threshold Hydraulic Loading for C** (m/yr) 3500 3500 3500 3500
Horizontal Flow Coefficient 3 3 3 3 3
Reuse Enabled On Off On On Off Off On Off Off
Max drawdown height (m) 1.997 1.997 1.997 1.997
Annual Demand Enabled Off Off Off Off Off Off Off Off Off
Daily Demand Enabled On Off On On Off Off On Off Off
Daily Demand Value (ML/day) 0.00156 0.00078 0.00234 0.00078
Custom Demand Enabled Off Off Off Off Off Off Off Off Off
Filter area (sqm) 20 10 20 10 10
Filter perimeter (m) 0.01 0.1 0.01 0.1 0.1
Filter depth (m) 0.5 0.5 0.5 0.5 0.5
Filter Median Particle Diameter (mm)
Saturated Hydraulic Conductivity (mm/hr) 200 200 200 200 200
Section 21
Infiltration Media Porosity 0.35 0.35 0.35 0.35 0.35
Vegetation Type Vegetated with Effective Nutrient Removal Plants Vegetated with Effective
Vegetated
Nutrient
with Removal
Effective Nutrient
Plants Removal
Vegetated
Plants
with Effective
VegetatedNutrient
with Effective
RemovalNutrient
Plants Removal Plants
Total Nitrogen Content in Filter (mg/kg) 400 400 400 400 400
Orthophosphate Content in Filter (mg/kg) 50 50 50 50 50
Is Base Lined? Yes No Yes No No
Is Underdrain Present? Yes Yes Yes Yes Yes
Is Submerged Zone Present? No No No No No
Submerged Zone Depth (m)
B for Media Soil Texture -9999 13 -9999 -9999 13 13 -9999 13 13
Proportion of upstream impervious area treated
Exfiltration Rate (mm/hr) 0 0 0 0 0 0 0 0 0
Evaporative Loss as % of PET 0 100 0 0 100 100 0 100 100
Sfc 0.37 0.61 0.37 0.61 0.61
S* 0.22 0.37 0.22 0.37 0.37
Sw 0.11 0.11 0.11 0.11 0.11
Sh 0.05 0.05 0.05 0.05 0.05
Emax (m/day) 0.008 0.008 0.008 0.008 0.008
Ew (m/day) 0.001 0.001 0.001 0.001 0.001
IN - Mean Annual Flow (ML/yr) 1.43 3.32 0.483 2.3 0.28 3.34 0.753 0.493 0.506
IN - TSS Mean Annual Load (kg/yr) 41.4 312 14.3 69.1 114 383 22.5 194 200
IN - TP Mean Annual Load (kg/yr) 0.234 1.14 8.13E-02 0.381 0.181 0.927 0.125 0.314 0.325
IN - TN Mean Annual Load (kg/yr) 3.01 6.77 1.01 4.85 0.588 6.83 1.58 1.02 1.07
IN - Gross Pollutant Mean Annual Load (kg/yr) 34 48 11.5 54.6 6.73 39.1 17.9 11.9 12.2
OUT - Mean Annual Flow (ML/yr) 0.972 3.29 0.267 1.6 0.252 3.31 0.52 0.465 0.478
OUT - TSS Mean Annual Load (kg/yr) 21.5 98 5.92 37.7 3.26 122 12 11.9 12.1
OUT - TP Mean Annual Load (kg/yr) 0.147 0.555 4.12E-02 0.246 3.06E-02 0.519 8.01E-02 6.55E-02 6.82E-02
OUT - TN Mean Annual Load (kg/yr) 1.97 3.93 0.534 3.26 0.182 4.03 1.05 0.386 0.406
OUT - Gross Pollutant Mean Annual Load (kg/yr) 0 0 0 0 0 0 0 0 0
Flow In (ML/yr) 1.43488 3.32347 0.483023 2.30134 0.279634 3.34428 0.752918 0.492723 0.50598
ET Loss (ML/yr) 0 0.0313676 0 0 0.0276559 0.0313258 0 0.0282718 0.0282996
Infiltration Loss (ML/yr) 0 0 0 0 0 0 0 0 0
Low Flow Bypass Out (ML/yr) 0 0 0 0 0 0 0 0 0
High Flow Bypass Out (ML/yr) 0 0 0 0 0 0 0 0 0
Orifice / Filter Out (ML/yr) 0.971584 1.92891 0.266873 1.60107 0.23461 1.90158 0.519857 0.395475 0.404553
Weir Out (ML/yr) 0.000396547 1.36158 0 0.00067307 0.0173304 1.40943 0.000350932 0.0688898 0.0731186
Transfer Function Out (ML/yr) 0 0 0 0 0 0 0 0 0
Reuse Supplied (ML/yr) 0.465593 0 0.217332 0.696997 0 0 0.234094 0 0
Reuse Requested (ML/yr) 0.573142 0 0.286571 0.845487 0 0 0.286571 0 0
% Reuse Demand Met 81.2353 0 75.8388 82.4373 0 0 81.6878 0 0
% Load Reduction 32.2604 0.992545 44.7494 30.3995 9.9035 0.994642 30.9078 5.75535 5.59485
TSS Flow In (kg/yr) 41.4082 311.965 14.2913 69.071 113.796 382.554 22.5124 194.012 199.851
TSS ET Loss (kg/yr) 0 0 0 0 0 0 0 0 0
TSS Infiltration Loss (kg/yr) 0 0 0 0 0 0 0 0 0
TSS Low Flow Bypass Out (kg/yr) 0 0 0 0 0 0 0 0 0
TSS High Flow Bypass Out (kg/yr) 0 0 0 0 0 0 0 0 0
TSS Orifice / Filter Out (kg/yr) 21.5032 3.81273 5.92287 37.6912 0.584977 3.72434 11.9606 0.973192 0.994765
TSS Weir Out (kg/yr) 0.00672733 94.1783 0 0.0136989 2.67453 118.606 0.00799951 10.897 11.1094
TSS Transfer Function Out (kg/yr) 0 0 0 0 0 0 0 0 0
TSS Reuse Supplied (kg/yr) 6.57433 0 2.99638 10.0604 0 0 3.35141 0 0
TSS Reuse Requested (kg/yr) 0 0 0 0 0 0 0 0 0
TSS % Reuse Demand Met 0 0 0 0 0 0 0 0 0
TSS % Load Reduction 48.0539 68.5891 58.5561 45.4114 97.1357 68.0228 46.8355 93.8817 93.9434
TP Flow In (kg/yr) 0.234185 1.13452 0.0813239 0.381385 0.180666 0.92671 0.125463 0.313745 0.325195
TP ET Loss (kg/yr) 0 0 0 0 0 0 0 0 0
TP Infiltration Loss (kg/yr) 0 0 0 0 0 0 0 0 0
TP Low Flow Bypass Out (kg/yr) 0 0 0 0 0 0 0 0 0
TP High Flow Bypass Out (kg/yr) 0 0 0 0 0 0 0 0 0
TP Orifice / Filter Out (kg/yr) 0.14676 0.186584 0.0411522 0.245994 0.0243633 0.183467 0.0800128 0.0408838 0.0418107
TP Weir Out (kg/yr) 6.51E-05 0.36863 0 0.000110687 0.0061887 0.335029 4.54E-05 0.0245468 0.026385
[OCR of page images]
Infiltration Media Porosity
Vegetation Type
Total Nitrogen Content in Filter (mg/kg)
Orthophosphate Content in Filter (mg/kg)
Is Base Lined?
Is Underdrain Present?
Is Submerged Zone Present?
Submerged Zone Depth (m)
B for Media Soil Texture
Proportion of upstream impervious area treated
Exfiltration Rate (mm/hr)
Evaporative Loss as % of PET
Sfc
st
Sw
Sh
Emax (m/day)
Ew (m/day)
IN - Mean Annual Flow (ML/yr)
IN - TSS Mean Annual Load (kg/yr)
IN - TP Mean Annual Load (kg/yr)
IN - TN Mean Annual Load (kg/yr)
IN - Gross Pollutant Mean Annual Load (kg/yr)
OUT - Mean Annual Flow (ML/yr)
OUT - TSS Mean Annual Load (kg/yr)
OUT - TP Mean Annual Load (kg/yr)
OUT - TN Mean Annual Load (kg/yr)
OUT - Gross Pollutant Mean Annual Load (kg/yr)
Flow In (ML/yr)
ET Loss (ML/yr)
Infiltration Loss (ML/yr)
Low Flow Bypass Out (ML/yr)
High Flow Bypass Out (ML/yr)
Orifice / Filter Out (ML/yr)
Weir Out (ML/yr)
Transfer Function Out (ML/yr)
Reuse Supplied (ML/yr)
Reuse Requested (ML/yr)
% Reuse Demand Met
% Load Reduction
TSS Flow In (kg/yr)
TSS ET Loss (kg/yr)
TSS Infiltration Loss (kg/yr)
TSS Low Flow Bypass Out (kg/yr)
TSS High Flow Bypass Out (kg/yr)
TSS Orifice / Filter Out (kg/yr)
TSS Weir Out (kg/yr)
TSS Transfer Function Out (kg/yr)
TSS Reuse Supplied (kg/yr)
TSS Reuse Requested (kg/yr)
TSS % Reuse Demand Met
TSS % Load Reduction
TP Flow In (kg/yr)
TP ET Loss (kg/yr)
TP Infiltration Loss (kg/yr)
TP Low Flow Bypass Out (kg/yr)
TP High Flow Bypass Out (kg/yr)
TP Orifice / Filter Out (kg/yr)
TP Weir Out (kg/yr)
-9999
1.43
414
0.234
3.01
34
0.972
21.5
0.147
1.97
0
1.43488
0
0
0
0
0.971584
0.000396547
0
0.465593
0.573142
81.2353
32.2604
41.4082
0
0
0
0
21.5032
0.00672733
0
6.57433
0
0
48.0539
0.234185
0
0
0
0
0.14676
6.51E-05
0.35
Effective Nutrient
400
50
Yes
Yes
No
13
0
100
0.37
0.22
0.11
0.05
0.008
0.001
3.32
312
1.14
6.77
48
3.29
98
0.555
3.93
0
3.32347
0.0313676
0
0
0
1.92891
1.36158
0
0
0
0
0.992545
311.965
ooo
0
3.81273
94.1783
0
0
0
0
68.5891
1.13452
0
0
0
0
0.186584
0.36863
-9999
0.483
14.3
8.13E-02
1.01
15
0.267
5.92
4.12E-02
0.534
0
0.483023
0
0
0
0
0.266873
0
0
0.217332
0.286571
75.8388
44.7494
14.2913
0
0
0
0
5.92287
0
0
2.99638
0
0
58.5561
0.0813239
0
0
0
0
0.0411522
0
-9999
23
69.1
0.381
4.85
54.6
1.6
37.7
0.246
3.26
0
2.30134
0
0
0
0
1.60107
0.00067307
0
0.696997
0.845487
82.4373
30.3995
69.071
0
0
0
0
37.6912
0.0136989
0
10.0604
0
0
45.4114
0.381385
0
0
0
0
0.245994
0.0001 10687
0.35 0.35
Effective Nutrient Effective Nutrient
400 400
50 50
No Yes
Yes Yes
No No
13 13
0 0
100 100
0.61 0.37
0.37 0.22
0.11 0.11
0.05 0.05
0.008 0.008
0.001 0.001
0.28 3.34
114 383
0.181 0.927
0.588 6.83
6.73 39.1
0.252 3.31
3.26 122
3.06E-02 0.519
0.182 4.03
0 0
0.279634 3.34428
0.0276559 0.0313258
0 0
0 0
0 0
0.23461 1.90158
0.0173304 1.40943
0 0
0 0
0 0
0 0
9.9035 0.994642
113.796 382.554
0 0
0 0
0 0
0 0
0.584977 3.72434
2.67453 118.606
0 0
0 0
0 0
0 0
97.1357 68.0228
0.180666 0.92671
0 0
0 0
0 0
0 0
0.0243633 0.183467
0.0061887 0.335029
-9999
0.753
22.5
0.125
1.58
17.9
0.52
12
8.01E-02
1.05
0
0.752918
0
0
0
0
0.519857
0.000350932
0
0.234094
0.286571
81.6878
30.9078
22.5124
0
0
0
0
11.9606
0.00799951
0
3.35141
0
0
46.8355
0.125463
0
0
0
0
0.0800128
4.54E-05
Effective Nutrient =ffective Nutrient Removal Plants
0.35 0.35
400 400
50 50
No No
Yes Yes
No No
13 13
0 0
100 100
0.61 0.61
0.37 0.37
0.11 0.11
0.05 0.05
0.008 0.008
0.001 0.001
0.493 0.506
194 200
0.314 0.325
1.02 1.07
11.9 12.2
0.465 0.478
11.9 124
6.55E-02 6.82E-02
0.386 0.406
0 0
0.492723 0.50598
0.0282718 0.0282996
0 0
0 0
0 0
0.395475 0.404553
0.0688898 0.0731186
0 0
0 0
0 0
0 0
5.75535 5.59485
194.012 199.851
0 0
0 0
0 0
0 0
0.973192 0.994765
10.897 11.1094
0 0
0 0
0 0
0 0
93.8817 93.9434
0.313745 0.325195
0 0
0 0
0 0
0 0
0.0408838 0.0418107
0.0245468 0.026385
Section 22
TP Transfer Function Out (kg/yr) 0 0 0 0 0 0 0 0 0
TP Reuse Supplied (kg/yr) 0.0630408 0 0.0293623 0.0955881 0 0 0.031819 0 0
TP Reuse Requested (kg/yr) 0 0 0 0 0 0 0 0 0
TP % Reuse Demand Met 0 0 0 0 0 0 0 0 0
TP % Load Reduction 37.3038 51.0617 49.3971 35.4708 83.0893 44.0498 36.1896 79.1453 79.0293
TN Flow In (kg/yr) 3.01389 6.77252 1.01001 4.84616 0.588081 6.83109 1.57812 1.02304 1.06678
TN ET Loss (kg/yr) 0 0 0 0 0 0 0 0 0
TN Infiltration Loss (kg/yr) 0 0 0 0 0 0 0 0 0
TN Low Flow Bypass Out (kg/yr) 0 0 0 0 0 0 0 0 0
TN High Flow Bypass Out (kg/yr) 0 0 0 0 0 0 0 0 0
TN Orifice / Filter Out (kg/yr) 1.96771 1.16214 0.534032 3.26018 0.145408 1.14383 1.04842 0.246859 0.252339
TN Weir Out (kg/yr) 0.000812683 2.76557 0 0.00132098 0.0365539 2.88716 0.000694545 0.13913 0.153705
TN Transfer Function Out (kg/yr) 0 0 0 0 0 0 0 0 0
TN Reuse Supplied (kg/yr) 0.842959 0 0.387835 1.27452 0 0 0.425094 0 0
TN Reuse Requested (kg/yr) 0 0 0 0 0 0 0 0 0
TN % Reuse Demand Met 0 0 0 0 0 0 0 0 0
TN % Load Reduction 34.685 42.0053 47.1263 32.6994 69.0583 40.9904 33.521 62.2704 61.9374
GP Flow In (kg/yr) 34.0252 48.0141 11.4541 54.575 6.73447 39.1425 17.8548 11.8652 12.1856
GP % Reuse Demand Met 0 0 0 0 0 0 0 0 0
GP % Load Reduction 100 100 100 100 100 100 100 100 100
PET Scaling Factor 1 2.1 1 2.1 2.1
No Generic treatment nodes
Other nodes
Location Receiving Node - Tributary of Wooroi Ck
ID 1
Node Type ReceivingNode
IN - Mean Annual Flow (ML/yr) 8.32
IN - TSS Mean Annual Load (kg/yr) 260
IN - TP Mean Annual Load (kg/yr) 1.32
IN - TN Mean Annual Load (kg/yr) 9.99
IN - Gross Pollutant Mean Annual Load (kg/yr) 0
OUT - Mean Annual Flow (ML/yr) 8.32
OUT - TSS Mean Annual Load (kg/yr) 260
OUT - TP Mean Annual Load (kg/yr) 1.32
OUT - TN Mean Annual Load (kg/yr) 9.99
OUT - Gross Pollutant Mean Annual Load (kg/yr) 0
% Load Reduction 17.4
TSS % Load Reduction 79.8
TN % Load Reduction 52.4
TP % Load Reduction 59.7
GP % Load Reduction 100
Links
Drainage Drainage Drainage Drainage Drainage Drainage Drainage Drainage
Location Drainage Link Drainage Link Drainage Link Drainage Link Drainage Link Drainage Link Drainage Link Drainage Link Drainage Link Drainage Link Link Link Link Link Link Link Link Link Drainage Link
Source node ID 2 7 6 8 9 13 15 10 3 16 5 18 19 14 12 4 20 17 11
Target node ID 3 4 7 9 12 14 4 11 4 17 12 4 20 1 1 1 1 1 1
Muskingum-Cunge Routing Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed Not Routed
Muskingum K
Muskingum theta
IN - Mean Annual Flow (ML/yr) 1.43 0.267 0.483 2.3 1.6 0.753 0.588 0.28 0.972 0.493 1.74 1.5 0.506 0.52 3.31 3.29 0.478 0.465 0.252
IN - TSS Mean Annual Load (kg/yr) 41.4 5.92 14.3 69.1 37.7 22.5 0.415 114 21.5 194 345 284 200 12 122 98 12.1 11.9 3.26
IN - TP Mean Annual Load (kg/yr) 0.234 4.12E-02 8.13E-02 0.381 0.246 0.125 0.366 0.181 0.147 0.314 0.681 0.581 0.325 8.01E-02 0.519 0.555 6.82E-02 6.55E-02 3.06E-02
IN - TN Mean Annual Load (kg/yr) 3.01 0.534 1.01 4.85 3.26 1.58 1.22 0.588 1.97 1.02 3.57 3.05 1.07 1.05 4.03 3.93 0.406 0.386 0.182
IN - Gross Pollutant Mean Annual Load (kg/yr) 34 0 11.5 54.6 0 17.9 14.4 6.73 0 11.9 39.1 33.6 12.2 0 0 0 0 0 0
OUT - Mean Annual Flow (ML/yr) 1.43 0.267 0.483 2.3 1.6 0.753 0.588 0.28 0.972 0.493 1.74 1.5 0.506 0.52 3.31 3.29 0.478 0.465 0.252
OUT - TSS Mean Annual Load (kg/yr) 41.4 5.92 14.3 69.1 37.7 22.5 0.415 114 21.5 194 345 284 200 12 122 98 12.1 11.9 3.26
Section 23
OUT - TP Mean Annual Load (kg/yr) 0.234 4.12E-02 8.13E-02 0.381 0.246 0.125 0.366 0.181 0.147 0.314 0.681 0.581 0.325 8.01E-02 0.519 0.555 6.82E-02 6.55E-02 3.06E-02 OUT - TN Mean Annual Load (kg/yr) 3.01 0.534 1.01 4.85 3.26 1.58 1.22 0.588 1.97 1.02 3.57 3.05 1.07 1.05 4.03 3.93 0.406 0.386 0.182 OUT - Gross Pollutant Mean Annual Load (kg/yr) 34 0 11.5 54.6 0 17.9 14.4 6.73 0 11.9 39.1 33.6 12.2 0 0 0 0 0 0 Catchment Details Catchment Name Cooroy_1973to1983_6min_CarramarExtension_Dec2017 Timestep 6 Minutes Start Date 1/01/1973 End Date 1/01/1983 23:54 Rainfall Station 40059 COOROY ET Station User-defined monthly PET Mean Annual Rainfall (mm) 1550 Mean Annual ET (mm) 1632
Section 24
Callaghan & Toth
APPENDIX B - Preliminary Design of Stormwater
Detention Volume – BSM Report
B
1714-Cartwrigth Village Extension_IWMP.doc January 2018
Section 25
NOOSA CARE INC
CARTWRIGHT VILLAGE EXTENSION
CARRAMAR, COOROY NOOSA ROAD, TEWANTIN
PRELIMINARY DESIGN OF
STORMWATER DETENTION VOLUME
21 DECEMBER 2017
Section 26
CARTWRIGHT VILLAGE EXTENSION AT CARRAMAR
COOROY – NOOSA ROAD, TEWANTIN
PRELIMINARY DESIGN OF STORMWATER DETENTION VOLUME
REPORT COMPILED FOR NOOSA CARE INC
BY BRISBANE STORMWATER MANAGEMENT PTY LTD
DOCUMENT CONTROL
BSM Job No: 2017-11
Doc Filename Status Format Issued To Date
Carramar.Doc Draft Pdf Callaghan & Toth P/L 19/12/17
BSM-Office 19/12/17
Carramar.Doc Final Pdf Callaghan & Toth P/L 21/12/17
21/12/17
COPYRIGHT
This report is confidential and is proprietary to Brisbane Stormwater Management Pty Ltd and their
client Noosa Care Inc. The report is provided to Noosa Care Inc’s civil consultant Callaghan & Toth Pty
Ltd and to Noosa Council for the purpose of defining a stormwater detention basin that will mitigate the
increased stormwater runoff rates from the proposed extension of Cartwright Village at Carramar, on
the Cooroy-Noosa Roadd at Tewantin. It may not be used by any other party or for any other purpose
whatsoever without the written permission of both Brisbane Stormwater Management Pty Ltd and
Noosa Care Inc.
Brisbane Stormwater Management Pty Ltd and Noosa care Inc will not accept any responsibility for any
losses suffered by any other party as a result of the unauthorised use of this report.
CERTIFICATION
I hereby certify that the stormwater detention volume defined in this report has been designed by
industry-standard procedures and that the Noosa Council can rely on the design details described herein
during their consideration of the relevant matters for approval.
………………………………………………
Denis Ogle, RPEQ 2405, 21 December 2017
Director, Brisbane Stormwater Management P/L
92 Alkoomie St, PO Box 8119, Wynnum Nth, Q4178
Ph (07)33963383, Email: [email protected]
Page 1
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 27
List Of Contents
1. Introduction And Summary 3
2. Pre- And Post-Development Runoff Rates By The Rational Method 4
3. Broad-Brush Detention Volume 4
4 Pre- And Post-Development Urbs Models 5
4.1 Model Set-Ups 5
4.2 Comparison To Rational Method Calculations 7
4.3 Detention Volumes 7
5. References 9
List Of Figures
1. Overall Site Plan 2
2. Urbs Model Layout For Pre-Development Scenario 5
3. Urbs Model Layout For Post-Development Scenario 6
4. Conceptual Arrangement Of Detention Volume 8
List Of Tables
1. Comparison of Urbs Outflow Rates To Rational Method Outflow Rates 7
2 Urbs Design Of Attenuation Volume, Regardless Of Critical Durations 7
Appendices
A. EcoAid Brochure 12
B. Urbs catchment File, Pre-Development Scenario 23
C. Urbs Catchment File, Post-Development Scenario 26
Page 2
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 28
1.0 INTRODUCTION AND SUMMARY
This report has been prepared by Brisbane Stormwater Management P/L at the request of Noosa Care
Inc’s civil consultant Callaghan & Toth P/L. The report describes the definition of a stormwater
detention volume for the management of peak rates of stormwater runoff from the proposed extension
of Cartwright Village at Carramar, at 186 Cooroy – Noosa Road, Tewantin. A plan of the overall site,
including the existing facilities and the proposed extension, is shown in Figure 1 below below.
The eastern boundary of the 4 hectare site borders a tributary of Wooroi Creek, and stormwater runoff
from the entire site discharges to that tributary. The 0.82 hectare stormwater catchment area for the
proposed extension is outlined in red on Figure 1.
SITE BDY
VILLA 5
VILLA 6
VILLA 4
WATER
EXISTING FACILITIES HOLE
VILLA 3 PROPOSED
EK
EXTENSION
CRE
ENTRY
LANDSCAPED
PODIUM
VILLA 1 VILLA 2
SITE BD NORTH
Y
STORMWATER CATCHMENT BOUNDARY
FOR POPOSED EXTENSION COOROY - NOOSA ROAD
Figure 1: Overall Site Plan
The design catchment is mostly open space at present, with a car-park and some pathways constituting
an impervious fraction of 22 percent. The proposed extension will consist of an entry facility and seven
villas, with associated pathways and podium areas and an extension of the existing carpark under two of
the proposed villas, which will increase the catchment’s impervious fraction to 65 percent.
Urbs modelling of the pre-development and post-development scenarios has indicated that the proposed
extension will increase the peak runoff rates from the site by about 35 percent. The modelling has
further indicated that complete mitigation of this increase will require a detention volume of 118 cubic
metres if the difference in critical storm durations between the pre- and post-development scenarios is
ignored; or as much as 140 cubic metres for complete mitigation at like-for-like durations.
An arrangement of underground detention cells, based on the ecoAid system, and providing a total
detention volume of 131 cubic metres, is shown in Figure 4 on page 12 of this report. A description of
the ecoAID system is shown in Appendix A hereto.
It is expected that the required detention volume will be slightly reduced at the detailed design phase.
Page 3
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 29
2.0 PRE- AND POST-DEVELOPMENT RUNOFF RATES BY THE RATIONAL METHOD
The Rational Method has been used in this study as a sanity-check on the flow rates predicted by the
Urbs models.
Pre-Development:
The pre-development topography, cover and drainage pattern of the 0.82 hectare design catchment can
be seen in Figure 2 on page 6 of this report. The pre-development C10 runoff coefficient, for an
impervious fraction of 22 percent, is 0.744. The time of concentration, for sheet flow lengths of 60 to 70
metres at slopes of 3 to 4 percent through reasonably well-maintained grass and trees is 15 minutes. The
consequent pre-development peak flow rates are therefore calculated as follows:
Q100 = 0.00278 x 1.2 x 0.744 x 210 x 0.82 = 0.43 m3/sec
Q10 = 0.00278 x 1.0 x 0.744 x 145 x 0.82 = 0.25 m3/sec
Q1 = 0.00278 x 0.8 x 0.744 x 85 x 0.82 = 0.11 m3/sec
Post-Development:
The post -development cover and drainage pattern can be seen in Figure 2 on page 6 of this report. The
pre-development C10 runoff coefficient, for an impervious fraction of 65 percent, is 0.830. The time of
concentration, for sheet flow lengths of 20 to 25 metres at slopes of 3 to 4 percent through well-
maintained grass and trees, followed by 40 to 50 metres of allotment piping at 1 m/sec, is 10 minutes.
The consequent post-development peak flow rates are therefore calculated as follows:
Q100 = 0.00278 x 1.2 x 0.830 x 251 x 0.82 = 0.57 m3/sec
Q10 = 0.00278 x 1.0 x 0.830 x 173 x 0.82 = 0.33 m3/sec
Q1 = 0.00278 x 0.8 x 0.830 x 83 x 0.82 = 0.15 m3/sec
3.0 BROAD-BRUSH DETENTION VOLUME
The 43 percent in the catchment’s impervious fraction (from 22 percent to 65 percent) is about two
thirds of what would typically be expected for development of a medium-sized “Res A” lot. Given that
medium-sized “Res A” development generally requires about 250 cubic metres of detention volume for
each hectare of development platform, the proposed extension of facilities into the 0.82 hectare at
Cartwight Village should therefore be expected to require a detention volume in the order of:
Two-thirds of 250 x 0.82 = 137 cubic metres.
Page 4
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 30
4.0 PRE- AND POST-DEVELOPMENT URBS MODELS
4.1 Model Set-Ups
The model set-up for the pre-development scenario is shown in Figure 2, below. The model structure
has 14 subareas spread across five branches, or typically three subareas for each branch of the model.
This is comfortably more than the usually-preferred minimum of five subareas for an overall model, but
somewhat less than a minimum of five subareas per branch. Overall, the degree of model subdivision is
suggested to be adequate for the preliminary nature of this design study.
The corresponding coding of the Urbs catchment file for this pre-development scenario can be seen in
Appendix B hereto.
BDY BDY BDY FL OP BDY BDY
FL FL FL 9. 5 BDY FL
SMH GT
IL\600
CO NIC TB
CO CO TB DPY 600rcp
CO
CO 771
FL
9 .5
9.5 CO FL CO CO
FLLI CO
10 .0 FL CO CO
TB
FL CO
TB CO
FLCO
1
TB
TB CO
FL
10 .0
NORTH BR
CK
BR FL FL CO
CO COFL
CK
10 . 0 TB
CO
FL TB
CO
FL CK CO
BR bridge CO CO TB
3
BRCO CO CO
LI CO
CO CO CO FL
CO CO CO CK CK FL 774 872
CO CO
CO CO CO
FL CO
LI
COCOCO FL FL 873 871 870
CO
garden
LI CO FL CO CO
CO CO CO CO TB
BU BU FL
FL
CO CO
BUBU
BU CO CO
garden
fence line
CO
FL
CO
concrete path
CO
CO
CO
CO
BU BU
2
TB
FL
buil ding line
FL
FL
CO CO
CO CO
garden
BUFL
BU LI
FL
BU CO CO
CO NIC
4
FL COCO TB
FL CO
CO
FL CO
CO CORWL CO
CO
9 .0
CO RWL CO
RWLCORWL CO CO CO
CO
CO RWL
CO RWL
CO BB
RWL
CO CO
TANK TB
50 m
CO FL CO
0 SCALE
tank
CO TANK
TANK
FL FL CO TANK
TANK
BU BU TANK
TANK GT
IL\250 BB FL
tank
754
concrete path
BU BUFL TANK
TANK
TANK
building line
tank
TANK
250pvc
BB GE 751 922
TANK 750
8.5
FL
SV FL
fence line
BU
5
CO CO
BU
STORMWATER CATCHMENT BDY BU
BU
CO CO GE
653
TEXT
CO CO CO
BU CO
BU
FL FL
FOR PROPOSED EXTENSION BU FL
garden
652 FL 917 WATER
BU 645
CO
BU BU CO
CO 646
CO FL GE
CO COCO CO CO
CO CO
NIC
CO CO CO IL
SW
CO SHED IL\600
SW
IL\600 CO CO CO 915 TEXT
CO CO CO SHED 60
CO CO 0 rc
CO SHED p
CO CO CO CO
SHED SHED GE WATER
SHED
timber deck EMH 651
CO CO
FL HWHW
IL\600
shed
10 .0
HW 644 TEXT
DECK DECK HW TEXT cu
647 FL rr e
nt
OUT
642 650 sta
FL GE 648 649 nd
643 TEXT
8. 0
SHED FL
edge of swamp / mown area
in g
FL SHED FL wa
FL TB te
9 .5
rl in
TB TB e
top of bank
TB TEXT
KT
KC
KL
FL
FL
BB
BB FL
8 498
FL
WATER
7
TEXT
FL GE
KL
KC
KT FL
ch ain
FL 499
WATER
wire
KL
KC
KT
6 AWN
CO AWN
fence
CO
CO CO CO
CO CO CO CO TEXT
GE
COCOCO CO
CO
CO
CO CO FL
CO CO
FL CO CO
KLGATE gate GATE CO CO AWN CO CO GE
KC
KT AWN CO
FL GE FL CO CO GE
LI CO CO CONIC
CO CO CO CO
7.5
CO CO
CO CO TEXT
KL
KC
KT CO CO CO
CO CO
CO
GE CO CO CO TEXT GE
KL
KC
KT CO CO CO
CO
CO CO CO
CO
CO 906
CO CO
GE CO TEXT
CO CO FL
KLKC
KT LI CO CO
0 KT GE
.0 1
CO
GE CO CO 905
CO
CO GE CO CO GE
KL GE
KC
KTKT
CO
CO CO GE GE CO
CO GE CO
CO
CO GE
11
SV GE CO GE GE GE GE
CO
GE CO
CO GE GE
SW GE
IL\450 CO CO
CO GE
10
CO GE GE
KL
KC GU
9
KT CO
GE CO CO
CO GE CO
LI CO CO CO CO CO
GE 904
KL
KT TE FLAG CO CO
KC CO
1
CO
.5
CO EMH
0
CO CO CO CO CO
KL
KC CO CO CO CO CO
gully
CO CO CO CO CO CO TEXT
KT CO CO CO CO CO CO CO CO CO CO CO
CO CO CO CO CO CO CO CO CO
KL
KC CO CO CO CO CO FL
KT CO CO CO CO CO CO CO KT KT
CO CO CO CO CO CO CO CO KL KL Section 31
KT
KL IL\375
KT
KC LI CO CO CO CO CO KTKT
KLKT CO CO CO CO CO KT KT
KL 375pvc TEXT
KL CO KL FL
KL
KC
KT KT CO CO CO KLKL KL KL
KT KT CO CO
CO
IL\300
GT
IL\375 KT
KL
KL
KC
KT KC CO GT
IL\300 KLKT CO CO CO CO
KL KCKT CO CO CO KT
KL KL
KT KL
KT
KL
KC
KT KL CO CO KL
KT KT
KL KL KL
KT
KT
KCKC
KT KC
KT KC KL
KT
KT KL
KT KT
KT KT
KL
KC KL
KT KT
KLKT
KC KL KT KT
KL KL
KT KT
KC KC
KL KL
KTKT KL KT
KC KTKT
KC KL KL
KT
KT KL
KL
KT
KT
KTKC
KT KCKT 8. 5 KL KL KLKL
KLKT
KC KL KL KL KC KC KT KL
KT KT
KC 9 .0 KL KL GU TB
KT
KC KT KT KL KL KL KL TB
KL KTKT
KC kerb & ch.
KL KC 8 .5 BDY
KL
5
0.
1 TEXT OIP
KL
KT
KT
KL KT KL
KT
0 .0
KT
KL
KT KT
KL
KT
KT
KL KL
KLKL 1 KT
KL
KT KT
KL
KLKTKT
KT
KLKL
KL KT
KL KT
9 .5 KL
7.5 7.5
894
GPS TBGU TB
TEXT
12 13 14 KT KL
KL KT
TEXT
EXISTING CAR PARK 9 .0
KL KL
KT
FL
IL\450
8.0
KT
FL
9. 0
8 .5
FL FLBDY
COOROY - NOOSA ROAD
Figure 2: Urbs Model Layout For Pre-Development Scenario
Page 5
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 32
The model set-up for the post-development scenario is shown in Figure 3, below.. The model structure
has 17 subareas. Subareas 1 to 10 represent areas other than the proposed roofs, whereas subareas 11 to
18 represent the proposed roofs. The runoff from subareas 11 to 18 are conceptually lumped together
before passing through a single conceptual detention volume , before being conjoined with the sum of
the runoffs from subareas 1 to 10.
The corresponding coding of the Urbs catchment file for this post-development scenario can be seen in
Appendix C hereto.
NORTH
1
11 12
VILLA 5 VILLA 6
2
0 SCALE 50 m
3
STORMWATER CATCHMENT BDY 13
FOR PROPOSED EXTENSION VILLA 4
4 DB OUT
5
14
VILLA 3
15
ENTRY
6 7
LANDSCAPED
PODIUM
17 8
9 16
VILLA 2
VILLA 1
10
COOROY - NOOSA ROAD
Figure 3: URBS Model Layout For Post-Development Scenario
The pre-development and post-development models shared the same operating parameters – namely, an
alpha parameter of 2.0 and an m parameter of 0.80, with reach factor lengths varying from 1.9 to 2.5 in
Page 6
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 33
0.1 increments for ARI’s from 100 year down to 1 year. Rainfall intensities and temporal patterns were
ARR87 standard, and infiltration rates in both models were specified as zero initial loss and 2 mm/hour
continuing loss, as accepted by a Noosa Council representative in a telephone conversation of 12th
December 2017.
4.2 Comparison To Rational Method Calculations
The peak outflow rates from the Urbs models are compared to the Rational Method calculations in
Table 1, below. The Urbs outflow rates are consistently higher than the Rational Method calculations,
by as much as 18 – 20 percent at the 1 year level, reducing to 2 to 4 percent at the 100 year level.
Overall this is suggested to be an acceptable comparison.
Table 1: Comparison Of Urbs Outflow Rates To Rational Method Outflow Rates
ARI Pre-Development Model Post-Development Model (No Basin)
(years) Rational Method Urbs Diff Rational Method Urbs Diff
100 0.43 0.45 4% 0.57 0.58 2%
10 0.25 0.27 8% 0.33 0.37 12 %
1 0.11 0.13 18% 0.15 0.18 20 %
4.3 Detention Volumes
With the models deemed to be performing acceptable well, coding for a conceptual detention basin was
added to the post-development model, as can be seen in the catchment file in Appendix C. The coding
was adjusted so as to achieve a reasonably smooth storage-discharge curve while at the same time
ensuring that the outflows from the post-development scenario with the basin in place were reasonably
matched to the outflows from the pre-development scenario, regardless of any difference in the critical
storm durations between the pre- and post-development scenarios. The required 100 year detention
volume was found to be 118 cubic metres, with results across the range of ARI as in Table 2, below.
The 1 year outflow rate is attenuated exactly according to the requirement, while the 100 year outflow
rate is fractionally over-attenuated. Of the intervening ARI’s, there is a fractional shortfall in attenuation
at the 2 year level and a slightly beneficial degree of over-attenuation at the 2 year to 50 year ARI’s.
Overall, this volume is considered to provide an acceptable outcome, notwithstanding that the critical
storm durations were not necessarily the same, between the pre-development and post-development
models.
Table 2: Urbs Design Of Detention Volume, Regardless Of Critical Durations
ARI (years) Required Attenuation (m3/sec) Achieved Attenuation (m3/sec)
100 0.58 0.45 0.58 0.44
50 0.50 0.39 0.50 0.36
20 0.43 0.32 0.43 0.30
10 0.37 0.27 0.37 0.25
5 0.31 0.23 0.31 0.22
2 0.24 0.17 0.24 0.18
1 0.18 0.13 0.18 0.13
The models were then run for 100 year storm durations up to 3 hours, maintaining the same storm
durations in the pre-development and post-development models for each run. The 100 year 2 hour storm
was found to be the critical duration, resulting in a 100 year detention volume of 140 cubic metres.
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Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 34
In summary, the modelling has suggested a minimum 100 year detention volume of 118 cubic metres,
or maybe as much as 140 cubic metres if like-for-like storm durations are considered to be a vital
requirement. Both of these volumes are reasonably consistent with the broad-brush estimate of 137
cubic metres at the bottom of page 4 of this report. A nominal volume of 130 cubic metres was
therefore adopted, on the basis that the use of the latest infiltration allowances and temporal patterns at
the detailed design stage will most likely result in a slight reduction in the required detention volume,
albeit at the expense of substantially greater design complexity..
The 130 cubic metre volume was then simply apportioned between the three groups of roof areas, on
the basis of contributing roof area as a proportion of total roof area, resulting in the conceptual
arrangement shown in Figure 4 below. This provides a total of 131 cubic metres, using the ecoAID
underground cellular system. Details of this system are shown in the brochure in Appendix A hereto.
RW
NORTH
VILLA 5 VILLA 6
ecoAID SYSTEM
7 ROWS x 12 UNITS
SPLIT INTO 2 CELLS
DET VOL 61 m3
RW B5
0 SCALE 50 m
VILLA 4
ecoAID SYSTEM
3 ROWS x 9 UNITS
DET VOL 21 m3
RW
ecoAID SYSTEM
5 ROWS x 14 UNITS
DET VOL 49 m3
VILLA 3
TOTAL DETENTION VOLUME 131 m3
B4
ENTRY
RW B3
B1
VILLA 2
VILLA 1
B2
COOROY - NOOSA ROAD
Figure 4: Conceptual Arrangement Of Detention Volume
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Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 35
5.0 REFERENCES
1. Brisbane City Council, 1994 “URBS, The BCC Catchment Management Runoff Routing Model,
Version 3.3”
2. Noosa Council Planning Scheme Policies, 2015
3. Queensland Urban Drainage Manual, Third Edition, 2013
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Section 36
APPENDIX A
EcoAID Brochure
Page 10
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
Section 37
ecoAID ® Underground Stormwater Management [OCR of page images] Underground Stormwater Management
Section 38
ecoAID® OVERVIEW
ecoAID® is an underground modular stormwater physical screening, sedimentation and filtration
system used for detention, infiltration or harvesting techniques. The ecoAID® system is easily maintained
stormwater runoff. The system also provides from street level via the C-A-R utilising a Jet-Vac
stormwater treatment by utilising a ‘Catch-All-Row’ cleaning unit with a high pressure hose.
(C-A-R) as an internal gross pollutant and sediment
trap. The dual function of stormwater collection ecoAID® is an exceptionally strong and robust water
and treatment allows the engineer to optimise storage and treatment system that is capable of
the drainage layout by minimising the number of being used under public roads, car parks, sports
manhole pits, with the added benefit of omitting the fields and public open space. This provides the
need for external gross pollutant and sediment traps. engineer with opportunities to save valuable land
space and protect natural waterways from the
The ecoAID® chamber system can provide both damaging effects of pollution from both new and
primary and secondary treatment through the existing developments.
removal of gross pollutants and sediment via
ecoAID® Underground Stormwater Management
Section 39
The ecoAID® system is manufactured in Australia and ecoAID® can be installed in a single or double layer
is a proven cost effective alternative to imported configuration to meet project specific requirements.
systems. Local manufacture not only supports the
Australian manufacturing industry, it also provides ecoAID® has been used throughout Australia on
shorter product lead times and a financial boost to many types of projects including:
the local economy.
99 High end commercial developments
Each ecoAID® chamber weighs only 15kg allowing 99 Residential and sub-division
for safe and easy installation on site. Contractors 99 Local and State government projects including
are able to install ecoAID® quickly and efficiently schools and hospitals
meaning system installation times are reduced, 99 New sports fields for water harvesting
therefore saving on cost.
99 Drainage under public roads
99 Open sump conversions into Public Open Space
Section 40
SYSTEM DETAILS
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Section 41
ecoAID®
Technical Data
Chamber Volume (m3) 0.516m3
Min Installed Storage
(incl. 150mm rock bedding 0.822m3
and cover layer) ps = 0.40
Chamber Physical Length 1.00m
D
Chamber Installed Length 0.97m
B
Chamber Width 1.16m
Chamber Height 0.68m
Min Installed Storage Height
(incl. 150mm rock bedding 0.98m
and cover layer)
LEGEND:
A. ecoAID® EC1000 Chamber
B. ecoAID® EC1000 End Cap
C. bidim® A24 non-woven geotextile surround
D. bidim® Filter Wrap (over C-A-R)
E. 40kN Woven geotextile (along base of C-A-R)
1. Finished surface layer as specified by design engineer
2. Backfill material as specified by design engineer
3. 20-50mm Ø drainage rock/RCC/scoria
4. Subgrade
5. 150mm – 625mm Ø (OD) inlet pipe
6. Connecting pipe network
min < H > max
7. Manhole inlet structure
8. 100mm – 150mm Ø optional inspection/ventilation pipe
9. 100 – 150mm Ø optional lateral equalisation pipes
* The rock component provides additional storage and it's porosity
(typically 40%) is used when calculating the tanks overall storage
capacity.
* The ecoAID® system can be installed in a single or double layer
configuration.
* Please refer to our ecoAID® standard detail drawings for more
information.
ecoAID® COVER REQUIREMENTS
NOT SUBJECT TO Hmin Hmax
VEHICLE LOADING
eg - Public open space 300 2500
SUBJECT TO VEHICLE LOADING
not in roadway 450 2500
in sealed roadway 600 2500
under unsealed roadway 750 2500
minimum required values maximum allowable values
Section 42
5
4
1 2
6
KEY FEATURES & BENEFITS
1 Corrugated Arch Design – incorporating a true parabolic inner profile for
optimum load-shed via soil arching, with boxed-out corrugations providing arch
stiffness and rigidity ensuring structural integrity over the system’s 100 year+
design life. 3
2 Six slots per corrugation – Reducing chamber emptying time.
3 End Cap to close out row – Flat end cap base design ensuring no rotation of end
cap and chambers occurs when backfill material is placed. The end caps have cut
out guides accommodating pipe inlets up to 625mm outside diameter.
4 Moulded side entry ports (100mm Ø or 150mm Ø) – Integrated lateral pipe
ports allowing side entry lot connections directly into the ecoAID system and also
used to aid system equalisation and water distribution.
5 Moulded vertical entry ports (100mm Ø or 150mm Ø) – Integrated vertical pipe
ports to accommodate breather pipes for system ventilation, inspection access
7
and used for water extraction pipes on stormwater harvesting applications.
6 Keyed feet with stiffeners – The flat keyed feet of the chambers are locked
into place by the embedment aggregate preventing movement during backfill
placement and compaction.
7 Each chamber weighs only 15 kg – Can be installed by one person ensuring safe
and rapid installation. 8
8 Single or double layer configuration – Can be designed and installed in two
layers to increase effective volume.
ecoAID® Underground Stormwater Management
Section 43
STORMWATER QUALITY AND TREATMENT
‘Catch-All-Row’ (C-A-R)
The ecoAID® system utilises a stormwater treatment
device called a ‘Catch-All- Row’. The C-A-R retains gross
pollutants, sediment and other contaminants whilst
allowing clean water to enter into adjacent rows before
infiltrating into the surrounding soil or being discharged
downstream. The C-A-R row is connected to the inlet
pit and provides a large volume for sedimentation and
solid deposition (figure 1). This in turn enhances the
capabilities of stormwater treatment and greatly extends
the maintenance return intervals.
The C-A-R acts as a primary and secondary treatment
measure by removing gross pollutants and sediments
including total suspended solids (figure 2). The C-A-R can
also be used in conjunction with traditional treatment
measures as part of a wider external treatment train to (figure 1)
further improve the stormwater quality entering into
local waterways.
Geotextiles
Stormwater entering into the ecoAID® system is filtered
by a woven geotextile (figure 3) which is laid along
the base of each C-A-R and then ex-filtrates into the
stone bedding. Additional filtration and exfiltration of
stormwater occurs via the chamber slots which are
surrounded with a bidim® non-woven geotextile along
the entire length of the C-A-R (figure 3).
(figure 2)
Unique features of C-A-R
99 Large filtration area – each chamber has a large
surface area which permits filtration of stormwater
through the bottom woven geotextile.
99 Large sediment storage volume – greatly extending
maintenance return intervals.
99 Serviceable due to unimpeded access for cleaning.
Modelled in MUSIC
The ecoAID® system (i.e. C-A-R) can be modelled in
MUSIC and therefore the redundancy of additional GPTs
in certain conditions can be demonstrated – although in
some circumstances the use of additional filter media or
3rd party devices may be required to meet nutrient load
reduction targets.
(figure 3)
Section 44
ecoAID® FUNCTIONS
Infiltration
Infiltration tanks play an important role in Water by pipes and overland into the ecoAID® system
Sensitive Urban Design (WSUD) by aiding modern where the stormwater is temporarily stored before
stormwater construction practices and providing a infiltrating back into the natural ground.
‘sustainable’ solution which protects the environment
and takes advantage of natural site features and In order to improve the quality of stormwater
minimises any detrimental impact on the water cycle. run-off before infiltration takes place, ecoAID® utilises
an internal treatment device called the 'Catch-All-
There are many environmental and economic benefits Row'. The C-A-R effectively cleans and filters run-off
associated with onsite infiltration including reducing water by preventing gross pollutants and fine to
peak stormwater flows, reducing the quantity of coarse sediments from entering the storage rows of
stormwater runoff, reducing stormwater drainage the ecoAID® tank.
capital costs and improving stormwater quality.
In addition to improving stormwater quality, the large
The ecoAID® system can be used to control infiltration surface area provided by the base and side
stormwater at ‘source’ by managing stormwater walls of the ecoAID® system greatly enhances soakage
run-off from paved areas, impermeable roof tops, response and system emptying times ensuring local
rainwater tank overflows and soft landscaped areas. design requirements are achieved.
Runoff from each of these sources can be directed
Harvesting
Stormwater harvesting involves collecting, treating, storing
and re-using stormwater runoff from urban areas and is
considered to be a viable and cost effective alternative to
using local town water supplies. The typical stages of any
stormwater harvesting schemes are:
• Harvest (stormwater is collected from the source)
• Treat (to reduce pathogen and pollution levels)
• Store (to retain stormwater for re-use)
• Distribute (stormwater is distributed to the area of use)
ecoAID® Underground Stormwater Management
Section 45
Harvesting continued The ecoAID® system used in conjunction with a suitable liner system is an ideal solution for collecting, retaining and distributing treated stormwater for re-use in irrigation and toilet flushing applications on new sporting facilities, industrial complexes, new schools and hospital developments. ecoAID® is compatible with scoria, a light volcanic rock that plays a valuable role in algae buildup whereby a bioactive film on the scoria contributes to the removal of nitrogen and phosphorous. After initial gross pollutant, sediment and nutrient removal via ecoAID’s® ‘Catch-All-Row’ and scoria rock, further treatment takes place through the use of bio retention gardens, sand filters and UV disinfection (removal of bacteria and viruses) before being pumped to its area of use. Detention Traditional philosophy of stormwater management is to collect and dispose of stormwater runoff via a piped conveyance system as effectively and efficiently as possible in order to prevent flooding of properties and local streets. However, urbanisation and the increase in new developments means this method of stormwater management is no longer sustainable as it puts an ever increasing burden on existing drainage infrastructure and often leads to a number of environmental and economic issues. To help alleviate these problems the ecoAID® stormwater management system can be designed and constructed as a stormwater detention tank (with or without an impermeable liner) to meet both permissible site discharge and site storage requirements by acting as a water storage tank and releasing this water into the local drainage network at a controlled rate. ecoAID® can also be used as part of a stormwater quality and treatment management plan by providing primary or secondary treatment measures in the form of a proprietary ‘Catch-All-Row' which deals with both gross pollutants and a high percentage of total suspended solids (TSS).
Section 46
STRUCTURAL
ecoAID® is an exceptionally strong system that can withstand high loading conditions (live & dead loads). The
system draws its strength by distributing loads from above into the surrounding rock via soil arching.
The ecoAID® chamber system has been designed, manufactured and structurally tested in accordance with
ASTM F2787 (Standard Practice for Structural Design of Thermoplastic Corrugated Wall Stormwater Collection
Chambers). As per ASTM F2787 ecoAID® has been designed and independently assessed using finite element
analysis (FEA) and has undergone full scale field testing to validate model results. In addition, ecoAID® has been
load tested to the Australian standard AS 5100.2 (Bridge Design Code) meaning ecoAID® is suitable to be installed
under Australian roads and car parks.
ecoAID® is designed manufactured and tested What does AS 5100.2 mean?
to ASTM F2787.
99 Australian factored design wheel loads to a very
• Is made from injection moulded virgin polypropylene high standard.
(PP) co-polymer with high impact and creep
resistance, and UV-stabilised masterbatch resin. 99 ecoAID® can accommodate M1600 moving axle
loads of 16 tonne per axle (1.8 Live Load FoS)
• Has been independently assessed using FEA (ASTM
clause 5.5 & 6.1). 99 ecoAID® can accommodate W80 wheel loads of 8
tonne per wheel (1.8 Live Load FoS).
• Has undergone full scale field testing to validate
structural results (ASTM clause 9.1). 99 ecoAID® can accommodate tyre contact pressures
up to 800 kPa over an area of 0.1m2 @ 600mm
• Has been assessed using 100 year creep values cover.
(elastic modulus E) for both short term live loads and
long term dead loads. 99 ecoAID® exceeds AS3996 Class D rating for
carriageways of roads & areas open to commercial
• Exceeds the following serviceability requirements vehicles.
(deflection limits).
99 ecoAID® has considered short term live loads and
99 Localised buckling of chamber walls long term dead loads within in service conditions.
99 Tensile strength of chamber walls It is extremely important for any underground stormwater
collection system to be designed, manufactured and tested
99 Global buckling of chamber walls to a recognised standard as this protects the end user and
ensures the system is suitable for use under Australian
99 Foundation material stresses roads and car parks.
99 Subgrade material stresses Please request a copy of our ‘ecoAID® EC-1000 Stormwater
• Has been load tested to AS 5100.2 Chamber Analysis’ report for more details.
ecoAID® Underground Stormwater Management
Section 47
MAINTENANCE & INSPECTION
To minimise OH&S risks the inspection procedure is A maintenance schedule needs to be established
carried out from the surface via the access structure for each individual location based upon site specific
connected to the 'Catch-All-Row' or from the vertical variables such as:
inspection pipe. The inspections are visual and will verify
• Type of land – industrial, commercial, residential
the depth of pollutant built up within the row.
• Anticipated pollutant load
The maintenance procedure is carried out with the Jet- • Percent imperviousness
Vac process which utilises a high pressure water hose.
• Climate
The pressure of the nozzle propels the hose to the end
of the C-A-R while jetting and suspending sediments. An accurate maintenance interval can be determined by
As the nozzle is retrieved, the captured pollutants are regular, logged inspections, recommended at no more
flushed back into the manhole sump and vacuumed. than 6 monthly intervals initially.
Reducing maintenance costs
The environmental benefits of solids removal are well documented, however the more effective a system is at removing
contaminants and solids the more often it will need to be cleaned – yes? Well, not necessarily. It also depends on the
volume available for sedimentation and solids deposition. ecoAID® enables the designer to maximise this volume and
extend the maintenance return interval, so you spend less time and money cleaning out.
Section 48
ENVIRONMENTAL
100% RECYCLABLE
The system is 100% recyclable and has been load tested with recycled crushed construction waste for the rock drainage
media, potentially diverting many tonnes away from landfills.
AUSTRALIAN MANUFACTURED
ecoAID® is manufactured in Australia at a state-of-the-art ISO 9001 accredited manufacturing facility featuring low energy
consumption and servo-hydraulic plant with energy savings between 20 and 80%.
LOW CARBON FOOTPRINT AND CARBON MILES
With ecoAID® being manufactured in Australia, the ‘carbon miles’ are lower than imported systems. The stacking and
transportation efficiency makes ecoAID® chambers a sound environmental choice compared to oversize round pipe or
concrete tanks in detention and infiltration applications.
LONG SERVICE LIFE
ecoAID® is manufactured using injection moulded UV stabilised virgin polypropylene ensuring it meets its 100 year+
in service design life. The storage is serviceable due to unimpeded access to the ‘Catch-All-Row’ for cleaning and
maintenance from the ground surface level, so storage volume is not lost over time.
TECHNICAL SUPPORT
Geofabrics are able to provide technical support to design engineers, architects, developers and contractors. Our technical
hub can provide information relating to application suitability, system sizing, design specifications and full CAD design
suggestion drawings. Feel free to contact us directly using the details below, or visit our website where additional general
and technical information is available.
GEOFABRICS.CO
MELBOURNE SYDNEY NEWCASTLE COFFS HARBOUR PERTH ADELAIDE
(03) 8586 9111 (02) 8785 8800 (02) 4951 2688 (02) 6653 5706 (08) 6305 0561 (08) 8162 5855
BRISBANE TOWNSVILLE BUNDABERG GOLD COAST HOBART DARWIN
(07) 3279 1588 (07) 4774 8222 (07) 4155 9968 (07) 5594 8600 (03) 6273 0511 0407 523 669
ecoAID are registered trademarks of EcoAID Pty Ltd. EcoAID Pty Ltd is Australian owned and operated.
IMPORTANT NOTICE - DISCLAIMER - The information contained in this brochure is general in nature. In particular the content of this brochure does not take
account of specific conditions that may be present at your site. Site conditions may alter the performance and longevity of the product and in extreme cases
may make the product wholly unsuitable. Actual dimensions and performance may vary. If your project requires accuracy to a certain specified tolerance
level you must advise us before ordering the product from us. We can then advise whether the product will meet the required tolerances. Where provided,
installation instructions cover installation of product in site conditions that are conducive to its use and optimum performance. If you have any doubts as to
the installation instructions or their application to your site, please contact us for clarification before commencing installation. This brochure should not be
used for construction purposes and in all cases we recommend that advice be obtained from a suitably qualified consulting engineer or industry specialist
before proceeding with installation. © Copyright held by Geofabrics Australasia Pty Ltd. All rights are reserved and no part of this publication may be copied
without prior permission.
Section 49
APPENDIX B
URBS Catchment File, Pre-Development Scenario
Page 23
Brisbane Stormwater Management Pty Ltd Document File: Carramar.Doc
The text continues on section 50.