Original source · versioned page text
2160 IWMP Report_Jan2022
CHANGES MCU APPLICATION KABARA HOSTEL,
COOROY - NOOSACARE
INTEGRATED WATER MANAGEMENT PLAN
VERSION 0
FOR
NOOSA COUNCIL
LOT 102 on SP236318
20 TOPAZ STREET
COOROY
JANUARY 2022
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Callaghan & Toth
Civil, Environmental &
Hydraulic Engineers
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Callaghan & Toth
DOCUMENT HISTORY
Document Reference: No: 2160 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: Peter Middap
DISTRIBUTION LIST
POSITION ON
NAME ORGANIZATION REVISION 0 REVISION 1 REVISION 2
MANAGEMENT TEAM
Noosa Care Inc. Client
Peter Middap Middap Architects Architects
Lex Toth Callaghan & Toth Author
Noosa Council Assessment Officer
REVISION LIST
REVISION DATE DISTRIBUTED ISSUED BY CHECKED BY
0 27 January 2022 JD LT
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
2022
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CONTENTS
1. EXECUTIVE SUMMARY ......................................................................................................................5
2. INTRODUCTION ..................................................................................................................................5
3. DESCRIPTION .....................................................................................................................................6
3.1 Proposed Works ............................................................................................................................6
4. WATER QUALITY MANAGEMENT PLAN ..........................................................................................11
4.1 Proposed On-Site Stormwater Treatment Process ......................................................................11
4.2 MUSIC Model ..............................................................................................................................11
4.2.1 Source Nodes ......................................................................................................................11
4.2.2 Treatment Nodes .................................................................................................................12
4.2.3 Rainfall Data ........................................................................................................................13
4.3 MUSIC Modelling Results ............................................................................................................13
4.3.1 Water Quality Objectives .....................................................................................................13
4.3.2 Assessment of Results ........................................................................................................13
5 WATER CYCLE MANAGEMENT PLAN .............................................................................................16
6 FLOODING ASSESMENT REPORT ..................................................................................................16
6.1 Existing Conditions ......................................................................................................................16
6.2 Proposed Drainage System .........................................................................................................16
7 CONCLUSIONS & RECOMMENDATIONS ........................................................................................17
APPENDIX A: - MUSIC Results ......................................................................................................... A
APPENDIX B: - Site Photos ............................................................................................................... B
APPENDIX C: - DETENTION BASIN RESULTS ................................................................................. C
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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. 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.
7. Water by Design, Deemed to Comply Solutions – Stormwater Quality Management
(South East Queensland) (May 2010).
LIST OF FIGURES
Figure 1.1 Site Location Plan………………………………………………………….7
Plan No. 2160-01 Site Layout……………………….…………………………………………8
Plan No. 2160-02 Stormwater Drainage Plan – East……………………………………….9
Plan No. 2160-03 Stormwater Drainage Plan – West………………………………….......10
Figure 4.1 MUSIC Model for the Proposed Development…………………………14
Figure 4.2 Proposed Detention Tank…………………………………….................15
LIST OF TABLES
Table 4.1 MUSIC Catchment Areas………………………………………………..12
Table 4.2 Comparison of Load Reductions………………………………………..13
Table 6.1 Detention Storage……………….………………………………………..17
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1. EXECUTIVE SUMMARY
The key points of this investigation are as follows:
1. The NoosaCare Kabara site proposes to demolish the existing Kauri Building and
construct a new 2-storey building within a similar footprint as the existing building.
2. This will result in an increase in roof area of 544m2 and an additional 15 toilets in the
new building, compared to the existing building.
3. The increase in pollutant loads due to the increase in impervious areas (I.e. increased
roof area of Kauri Building) is to be attenuated.
4. Water saving devices for new fixtures are required.
5. Roof water runoff is to be recycled to provide Potable water to toilets and hose cocks.
6. The existing stormwater treatment system with the addition of one 24,000 litre rainwater
tank will be sufficient to achieve the required stormwater quality pollutant load reduction
targets, from any increases in pollutant load associated with the new Kauri Building
proposed for the site. The existing biobasin and bioswale do not need to be increased
in size to achieve the water quality targets.
7. The changes affect the stormwater detention requirements on site, and the installation of
two (2) x 4,000 litre stormwater tanks is adequate to attenuate flows to pre-development
conditions.
2. INTRODUCTION
This Integrated Water Management Plan (IWMP) report is supporting documentation for the
Changes Application relating to MCU13/0030.01 Multiple Housing Type 3 Retirements and
Special Needs for an additional 12 beds located at 20 Topaz Street, Cooroy – NoosaCare
Kabara site.
This IWMP is prepared for the MCU Changes 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 102 on SP236318 located at 20 Topaz Street, Cooroy
(Refer Site Location Plan Figure 1.1).
The IWMP considers the renewal of the Kauri Building and any associated hardstand areas.
The existing Kauri building roof area is approximately 2000m2, while the proposed Kauri
Building roof area is 2,544m2; this is an increase of 544m2. The existing total roof area that was
modelled in 2013 was 3,574m2 (which included the Cedar Building) and as such the new area
used in the MUSIC model is 4,118m2.
The existing hardstand areas are not proposed to change in area, that is the associated access
road, carparks and footpaths, and as such the total area remains the same at 958m2.
In order to receive planning approval from Noosa Council for the changes proposed on site (i.e.
increase in area of Kauri building), the site must demonstrate that it complies with the Integrated
Water Management Guidelines and that the storm water runoff will not change the surrounding
hydrology.
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Bioretention basin, bioswale and below ground roof water tank units 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. Two detention are required to
attenuate stormwater flows to predevelopment levels.
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. HydroCAD has been used to assess the site stormwater
detention requirements.
The rainwater tanks have been sized in accordance with Water by Design Music Guidelines
Version 1, December 2010 for landscaping and the Queensland Development Code MP4.3 for
toilet use.
3. DESCRIPTION
The site is bounded by Topaz Street to the north, Kauri Street road reserve (unformed road) to
the west, Cooroy Mountain Road to the east and vegetated property to the south. The use of
the site is an aged care facility, NoosaCare Kabara.
This site is subject to the ponding of floodwaters, with an unnamed tributary of Six Mile Creek
flowing along the southern boundary of the lot. This tributary flows to Lake MacDonald and is
within the Mary River catchment.
The flood search indicates that the Q100 year ARI flood levels do not impact on the habitable
floor levels of the buildings or carpark areas.
3.1 Proposed Works
It is proposed to demolish the existing Kauri building and construct a new building generally
within the same footprint of the existing building. The new building will result in the following:
Proposed new building – increases the beds from 84 to 96 beds, an extra 12 beds.
The new building will also have an extra 15 toilets, compared to the existing Kauri
building.
The roof area will increase by 544m2.
Features that won’t be impacted by these changes include:
Carparking to remain the same,
Access road to remain the same
Footpaths to remain the same
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 2160-01 shows the overall site layout. Plan 2160-02 and 2160-03 shows the treatment
and detention device locations.
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PROPOSED KABARA HOSTEL, COOROY
SITE LOCATION PLAN
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Ph: 54749081 Fax: 54749041 Figure 1 . 1
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Civil, Environmental &
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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.
2160-01. The proposed treatment train for the development site is illustrated on Plan No. 2160-
02 and 2160-03 listed below:
1. Three Rainwater tanks - Two existing Rainwater Tanks both 24,000 litre, collect water from
the Kauri and Cedar building rooves. The tanks are underground and have potable top-up
when 90% empty with an overflow pipe discharging to the bioretention basin.
An additional rainwater tank (24,000 litre) is proposed with the increase in roof area, to be
located with the existing tank located on the south-west corner of the Kauri building. The
tank capacity is to be adequate for the supply of washing machine cold water, toilets, and
landscaping.
2. One existing Bioswale collects water from the rainwater tanks and carparks areas. The
bioswale is 28m long with a filter media width of 1m, giving a filter media area of 28m2. This
bioswale flows to the biobasin which further treats the stormwater.
3. The existing Bioretention Basin treats the stormwater runoff from the access roads, car
parks, verge and rainwater tank overflow. The treated runoff is then directed to a vegetated
area within the property prior to flowing to the unnamed tributary of Six Mile Creek. The bio-
retention component will remove the nutrients, heavy metals, and retard flow.
The Bioretention Basin will be unlined and in combination with the rainwater tanks, act as a
Detention basin to attenuate stormwater flows from the site.
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 level 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.
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TABLE 4.1 MUSIC CATCHMENT AREAS (DEVELOPED)
Catchment Land Use Music Impervious Area (ha)
Habitable Roof Area Commercial 100% 0.3892
(Catchment A)
Car Park to Bio-retention Commercial 90% 0.0387
(Catchment B1)
Car Park to Bio-retention Commercial 90% 0.0571
(Catchment B2)
TOTAL 0.4850ha
4.2.2 Treatment Nodes
The “MUSIC Modelling Guidelines for South East Queensland” Version 1 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.
Rainwater Tanks have been provided for the roof catchment as shown on the plans. The Reuse
allowed is for:
1. A daily re-use onsite will be as follows: toilet reuse + laundry reuse = total reuse
2. Toilet Reuse: 21L/person/day per toilet = 21 litre x 1 person x 45 toilets = 945 L/day
3. Laundry Reuse = (pervious ground area) x (portion of area irrigation) x (annual irrigation
rate) = volume / year
= 1,030m2 x 75% x 0.548m = 546 kl/yr
Daily rate = 1467 L / day
Total Daily Reuse = 945 + 1,467 = 2,412 L/day
Three (3) tanks are proposed (2 existing and 1 new) a total of 72,000 litres on site, which will
supply reuse water. The overflow from the rainwater tanks flows to the bio-retention basin that
drains to the southern vegetated area within the site.
Bio retention Swale is adjacent the carpark in catchment B2 and will treat runoff from this
catchment and rainwater tank overflows. The bioretention swale is 1m wide at the base, 2.6m
wide overall and 28m long. It has a 1% grade flowing into the Bioretention Basin. The size of
this system has been designed in accordance with Plan 2160-03.
Bioretention Basin has been placed close to the edge of car parks to treat runoff from
Catchments B1, B2 and rainwater tank overflows. One (1) bio-retention basin has been used,
with an area of 36m2. It has a filter layer depth of 0.3m and an extended detention depth of
0.6m. The size and depth of the system has been designed in accordance with Water By
Design guidelines and this system is in place. The bio-retention basin drains to vegetated area
within the site.
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4.2.3 Rainfall Data
The meteorological data used for the MUSIC Model was the data for Cooroy from 01/01/1973 –
31/12/1983, as outlined in the MUSIC Modelling Guidelines for South East Queensland –
Version 1 December 2010.
The mean Annual Rainfall for Cooroy Composite 1973 – 83 = 1600mm
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 6.3.0 is 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 Water by Design Deemed to
Comply Solutions – Stormwater Quality Management (South East Queensland) version 1.0 –
Table A-2 (2010). The following have been included in Appendix 2:
The treatment train effectiveness for the system.
The MUSIC Version 6.3.0 Summary Report.
The information above indicates that the additions to the NoosaCare Kabara site and 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
REDUCTION LOAD
RESULT REDUCTION
TARGETS
Flow 12.5%
Total Suspended Solids 85% 80%
Total Phosphorous 59% 60%
Total Nitrogen 65% 45%
Gross Pollutants 100%
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’s 2160-01 to 03
shows the proposed locations of the rainwater tank, bio-retention swale and bio-retention basin.
The reductions listed in Section 4.3.1 above comply with Council’s requirements. Therefore, it is
considered that the proposed stormwater treatment system is currently sufficient to reduce the
pollutants prior to exiting the site. The 59% reduction of Total Phosphorus from the proposed
system is just below the target of 60%, which is considered within an acceptable error range.
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Civil, Environmental &
Hydraulic Engineers
14
[OCR of page images]
Catchment A (Roof Area) [Mixed]
2x 23,000 litre RWT
a
Catchment 82 - carparks & access road [Mixed] Bioretention Swale - Road
Se
Catchment B1 - carparks & access road [Mixed].
Bioretention Basin
Receiving Node - Tributary,__| |
Callaghan & Toth
Civil, Environmental &
Hydraulic Engineers
ABN. 45140292324
1.16/90 GOODCHAP ST
Noosaville Q 4566
Telephone (07) 54749081
Job No: 2160
project
PROPOSED KABARA HOSTEL
MUSIC MODEL FOR THE
PROPOSED DEVELOPMENT
www.callaghanandtoth.com.au
location
20 TOPAZ STREET
COOROY .
Figure 4.1
Scole: NTS DATE: JANUARY 2022 14
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Civil, Environmental &
Hydraulic Engineers
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ROOFWATER DOWNPIPES
|
DN150 OVERFLOW
PIPE TO GULLY PIT
FIRST FLUSH
DIVERTER
DN150 OUTLET TO
DN132 ORIFICE
4,000L TANK
{ASSUME TANK IS 0.8m DIA X 2.9m WIDTH x 1,8 HIGH)
project
Callaghan & Toth | PROPOSED KABARA HOSTEL EXTENSION TYPICAL DETENTION TANK
Civil, Environmental & location
Hydraulic Engineers | 99 TOPAZ STREET COOROY
Lo eet ee ;
—H pn: se74gost Fox 54749081 Figure 4.2
www.callaghanandtoth.com.au
Scale: NTS 15
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5 WATER CYCLE MANAGEMENT PLAN
This development has been designed to ‘Complying Solutions’ for Water Cycle Management.
To this end, 100% of the existing roof area and the increase in roof area for the new Kauri
building, being a total of 4,118m2 on the site will be connected to three rainwater tanks. The
tanks will have a capacity of 72,000 litres (three x 24,000 litre tanks) which is just below the
complying solutions requirement.
The rainwater tanks will supply water to cold water washing machine supply, toilet flushing and
hose cocks adjacent the building for hand watering of landscaping.
For landscaping the Water by Design Guidelines specify
Annual Irrigation Rate = 1,030m2 x 75% x 0.548m = 546 kl/yr
Daily irrigation rate = 1467 L / day
The tanks sizing can be 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
1500L/pedestal (toilet) @ 45 toilets = 67,500L
10 Day Demand Check
Landscape Area = (1,030m2x0.53m) ÷ 364 x 10 days demand = 15,000L for irrigation.
Total Storage for 10 day Supply = 67,500 + 15,000 = 83,500L
The proposed rainwater tank capacity is 72,000L which is short of the 10 day demand detailed
above. It is considered that this capacity will ensure stormwater quality targets are achieved,
and that reuse demand can be topped up by reticulated water supply for the site when tanks
shortfall.
6 FLOODING ASSESMENT REPORT
6.1 Existing Conditions
This site is subject to ponding of floodwaters from the adjacent channels and 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 Q2 flow. The overflow will discharge to the existing car park and existing
vegetated Bio-Swale.
The habitable minimum floor level for the new Kauri building is to be set at RL107.20 at the
ground level and the upper level is at RL110.62.
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The minimum carpark level is RL106.30, which is not affected by the Q100 flood level.
The applicant’s supplied flood certificate gives a minimum Q100 flood level of RL105.23 AHD
and a minimum floor level of RL106.7 AHD.
The MCU in 2013 detailed that the Bioretention basin has been modelled to act as a detention
basin. However, the increase in runoff from the additional roof area of 544m2 will be piped to
two (2) x 4,000 litre above-ground stormwater tanks which will attenuate the flow back to
predevelopment levels (see Figure 4.2). Runoff will then be directed to the biobasin which will
then treat the water to remove pollutants before releasing the stormwater into the existing gully
riparian zone.
HydroCAD was used to model a Q10 storm and Q100 storm back to predevelopment levels as
summarised in Table 6.1 and Appendix C.
This Material Change of Use application increases the roof area by 544m2 and as such, the
HydroCAD model has been updated to reflect this additional roof area. The hardstand areas
have not been reduced as a result of the building changes. The additional roof areas have been
modelled as footpath/landscape areas to ensure the same total square meterage is used in the
model.
TABLE 6.1: DETENTION STORAGE – for 2022 MCU application
PRE- PRE- POST POST
CATCHMENT DEVELOPMENT DEVELOPMENT DEVELOPMENT DEVELOPMENT
Q10 Q100 Q10 Q100
Old Roof + New
Roof (2022) +
0.13614m3/s 0.20514m3/s 0.13354m3/s 0.20421m3/s
Footpaths/Land
scape
7 CONCLUSIONS & RECOMMENDATIONS
The proposed increase in roof area for the new Kauri building can be treated by a treatment
train consisting of rainwater reuse tanks, bio-retention swale and bio-retention basin, which are
capable of removing the nutrients and heavy metals.
The existing car parking and new building can be built to flood free levels in accordance with
Council’s requirements.
The rainwater detention tanks and bioretention areas 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
2160, Kabara Upgrade, Cooroy IWMP.doc January 2022
Page 18
Callaghan & Toth
APPENDIX A: - MUSIC Results
A
2160, Kabara Upgrade, Cooroy IWMP.doc January 2022
Page 19
Source nodes
Catchment B2 - Catchment B1 -
Catchment A (Roof carparks & access carparks & access
Location Area) road road
ID 1 3 6
Node Type UrbanSourceNode UrbanSourceNode UrbanSourceNode
Zoning Surface Type Mixed Mixed Mixed
Total Area (ha) 0.412 0.057 0.039
Area Impervious (ha) 0.412 0.051367955 0.035146496
Area Pervious (ha) 0 0.005632045 0.003853504
Field Capacity (mm) 80 80 80
Pervious Area Infiltration Capacity coefficient - a 243 243 243
Pervious Area Infiltration Capacity exponent - b 0.6 0.6 0.6
Impervious Area Rainfall Threshold (mm/day) 1 1 1
Pervious Area Soil Storage Capacity (mm) 18 18 18
Pervious Area Soil Initial Storage (% of Capacity) 10 10 10
Groundwater Initial Depth (mm) 50 50 50
Groundwater Daily Recharge Rate (%) 0 0 0
Groundwater Daily Baseflow Rate (%) 31 31 31
Groundwater Daily Deep Seepage Rate (%) 0 0 0
Stormflow Total Suspended Solids Mean (log mg/L) 1.3 2.43 2.43
Stormflow Total Suspended Solids Standard Deviation (log mg/L) 0.38 0.38 0.38
Stormflow Total Suspended Solids Estimation Method Stochastic Stochastic Stochastic
Stormflow Total Suspended Solids Serial Correlation 0 0 0
Stormflow Total Phosphorus Mean (log mg/L) -0.89 -0.3 -0.3
Stormflow Total Phosphorus Standard Deviation (log mg/L) 0.34 0.34 0.34
Stormflow Total Phosphorus Estimation Method Stochastic Stochastic Stochastic
Stormflow Total Phosphorus Serial Correlation 0 0 0
Stormflow Total Nitrogen Mean (log mg/L) 0.37 0.37 0.37
Stormflow Total Nitrogen Standard Deviation (log mg/L) 0.34 0.34 0.34
Stormflow Total Nitrogen Estimation Method Stochastic Stochastic Stochastic
Stormflow Total Nitrogen Serial Correlation 0 0 0
Baseflow Total Suspended Solids Mean (log mg/L) 0 0.78 0.78
Baseflow Total Suspended Solids Standard Deviation (log mg/L) 0 0.39 0.39
Baseflow Total Suspended Solids Estimation Method Stochastic Stochastic Stochastic
Baseflow Total Suspended Solids Serial Correlation 0 0 0
Baseflow Total Phosphorus Mean (log mg/L) 0 -0.6 -0.6
Baseflow Total Phosphorus Standard Deviation (log mg/L) 0 0.5 0.5
Baseflow Total Phosphorus Estimation Method Stochastic Stochastic Stochastic
Baseflow Total Phosphorus Serial Correlation 0 0 0
Baseflow Total Nitrogen Mean (log mg/L) 0 0.32 0.32
Baseflow Total Nitrogen Standard Deviation (log mg/L) 0 0.3 0.3
Baseflow Total Nitrogen Estimation Method Stochastic Stochastic Stochastic
Baseflow Total Nitrogen Serial Correlation 0 0 0
Flow based constituent generation - enabled Off Off Off
OUT - Mean Annual Flow (ML/yr) 6.04 0.801 0.548
OUT - TSS Mean Annual Load (kg/yr) 174 318 218
OUT - TP Mean Annual Load (kg/yr) 1.07 0.555 0.372
OUT - TN Mean Annual Load (kg/yr) 19.3 2.53 1.76
OUT - Gross Pollutant Mean Annual Load (kg/yr) 140 18.5 12.6
Rain In (ML/yr) 6.55566 0.906974 0.620561
ET Loss (ML/yr) 0.518733 0.10559 0.0722463
Deep Seepage Loss (ML/yr) 0 0 0
Baseflow Out (ML/yr) 0 0 0
Imp. Stormflow Out (ML/yr) 6.03694 0.751687 0.514312
Perv. Stormflow Out (ML/yr) 0 0.0496517 0.0339723
Total Stormflow Out (ML/yr) 6.03694 0.801339 0.548284
Total Outflow (ML/yr) 6.03694 0.801339 0.548284
Page 20
Change in Soil Storage (ML/yr) 0 4.54E-05 3.10E-05
TSS Baseflow Out (kg/yr) 0 0 0
TSS Total Stormflow Out (kg/yr) 174.288 318.327 218.133
TSS Total Outflow (kg/yr) 174.288 318.327 218.133
TP Baseflow Out (kg/yr) 0 0 0
TP Total Stormflow Out (kg/yr) 1.06586 0.555138 0.371918
TP Total Outflow (kg/yr) 1.06586 0.555138 0.371918
TN Baseflow Out (kg/yr) 0 0 0
TN Total Stormflow Out (kg/yr) 19.3417 2.52645 1.75849
TN Total Outflow (kg/yr) 19.3417 2.52645 1.75849
GP Total Outflow (kg/yr) 139.658 18.4542 12.6265
No Imported Data Source nodes
USTM treatment nodes
Bioretention
Location 3 x 23_000 litre RWT Bioretention Basin Swale Swale - Road
ID 2 4 5 7
BioRetentionNodeV BioRetentionNod
Node Type RainWaterTankNode 4 SwaleNode eV4
Lo-flow bypass rate (cum/sec) 0 0 0.002 0.002
Hi-flow bypass rate (cum/sec) 100 100 100
Inlet pond volume 0
Area (sqm) 33.3 49.3 28
Initial Volume (m^3) 69
Extended detention depth (m) 0.1 0.3 0.2 0
Number of Rainwater tanks 3
Permanent Pool Volume (cubic metres) 69
Proportion vegetated 0
Equivalent Pipe Diameter (mm) 520
Overflow weir width (m) 10 0.2 2.8
Notional Detention Time (hrs) 4.64E-03
Orifice Discharge Coefficient 0.6
Weir Coefficient 1.7 1.7 1.7
Number of CSTR Cells 2 3 10 3
Total Suspended Solids - k (m/yr) 400 8000 8000 8000
Total Suspended Solids - C* (mg/L) 12 20 20 20
Total Suspended Solids - C** (mg/L) 12 14
Total Phosphorus - k (m/yr) 300 6000 6000 6000
Total Phosphorus - C* (mg/L) 0.13 0.13 0.13 0.13
Total Phosphorus - C** (mg/L) 0.13 0.13
Total Nitrogen - k (m/yr) 40 500 500 500
Total Nitrogen - C* (mg/L) 1.4 1.4 1.4 1.4
Total Nitrogen - C** (mg/L) 1.4 1.4
Threshold Hydraulic Loading for C** (m/yr) 3500 3500
Horizontal Flow Coefficient 3 3
Reuse Enabled On Off Off Off
Max drawdown height (m) 2.072
Annual Demand Enabled Off Off Off Off
Daily Demand Enabled On Off Off Off
Daily Demand Value (ML/day) 0.00241
Custom Demand Enabled Off Off Off Off
Custom Demand Time Series File
Custom Demand Time Series Units
Filter area (sqm) 36 28
Filter perimeter (m) 0.01 30
Filter depth (m) 0.3 0.6
Filter Median Particle Diameter (mm)
Saturated Hydraulic Conductivity (mm/hr) 200 200
Page 21
Infiltration Media Porosity 0.35 0.35
Length (m) 28
Bed slope 0.01
Base Width (m) 1
Top width (m) 2.6
Vegetation height (m) 0.25
Vegetated with
Vegetated with Effective
Effective Nutrient Nutrient
Vegetation Type Removal Plants Removal Plants
Total Nitrogen Content in Filter (mg/kg) 400 800
Orthophosphate Content in Filter (mg/kg) 50 50
Is Base Lined? Yes No
Is Underdrain Present? Yes Yes
Is Submerged Zone Present? No No
Submerged Zone Depth (m)
B for Media Soil Texture -9999 13 -9999 13
Proportion of upstream impervious area treated
Exfiltration Rate (mm/hr) 0 0 0 0
Evaporative Loss as % of PET 0 100 100
Sfc 0.37 0.37
S* 0.22 0.22
Sw 0.11 0.11
Sh 0.05 0.05
Emax (m/day) 0.008 0.008
Ew (m/day) 0.001 0.001
IN - Mean Annual Flow (ML/yr) 6.04 6.51 5.96 6
IN - TSS Mean Annual Load (kg/yr) 174 468 324 440
IN - TP Mean Annual Load (kg/yr) 1.07 1.42 1.19 1.4
IN - TN Mean Annual Load (kg/yr) 19.3 16.8 16.1 18.3
IN - Gross Pollutant Mean Annual Load (kg/yr) 140 21.5 10.3 18.5
OUT - Mean Annual Flow (ML/yr) 5.2 6.46 5.96 5.96
OUT - TSS Mean Annual Load (kg/yr) 121 103 250 324
OUT - TP Mean Annual Load (kg/yr) 0.846 0.815 1.05 1.19
OUT - TN Mean Annual Load (kg/yr) 15.8 8.3 15.1 16.1
OUT - Gross Pollutant Mean Annual Load (kg/yr) 0 0 8.85 10.3
Flow In (ML/yr) 6.03687 6.50275 5.9553 6.00046
ET Loss (ML/yr) 0 0.0512144 0 0.0387178
Infiltration Loss (ML/yr) 0 0 0 0
Low Flow Bypass Out (ML/yr) 0 0 2.25366 1.99429
High Flow Bypass Out (ML/yr) 0 0 0 0
Orifice / Filter Out (ML/yr) 5.19957 4.39023 3.01173 0.837272
Weir Out (ML/yr) 0 2.06324 0.693168 3.12924
Transfer Function Out (ML/yr) 0 0 0 0
Reuse Supplied (ML/yr) 0.840531 0 0 0
Reuse Requested (ML/yr) 0.884927 0 0 0
% Reuse Demand Met 94.983 0 0 0
% Load Reduction 13.8698 0.757787 -0.0547259 0.660859
TSS Flow In (kg/yr) 174.288 467.751 323.839 439.579
TSS ET Loss (kg/yr) 0 0 0 0
TSS Infiltration Loss (kg/yr) 0 0 0 0
TSS Low Flow Bypass Out (kg/yr) 0 0 141.181 166.769
TSS High Flow Bypass Out (kg/yr) 0 0 0 0
TSS Orifice / Filter Out (kg/yr) 121.252 9.93667 64.8943 1.9837
TSS Weir Out (kg/yr) 0 93.0868 43.6564 155.083
TSS Transfer Function Out (kg/yr) 0 0 0 0
TSS Reuse Supplied (kg/yr) 12.1533 0 0 0
TSS Reuse Requested (kg/yr) 0 0 0 0
Page 22
TSS % Reuse Demand Met 0 0 0 0
TSS % Load Reduction 30.4303 77.9747 22.8841 26.3303
TP Flow In (kg/yr) 1.06586 1.42001 1.1872 1.40118
TP ET Loss (kg/yr) 0 0 0 0
TP Infiltration Loss (kg/yr) 0 0 0 0
TP Low Flow Bypass Out (kg/yr) 0 0 0.470442 0.492491
TP High Flow Bypass Out (kg/yr) 0 0 0 0
TP Orifice / Filter Out (kg/yr) 0.846059 0.441958 0.426333 0.085508
TP Weir Out (kg/yr) 0 0.372802 0.152666 0.609107
TP Transfer Function Out (kg/yr) 0 0 0 0
TP Reuse Supplied (kg/yr) 0.116154 0 0 0
TP Reuse Requested (kg/yr) 0 0 0 0
TP % Reuse Demand Met 0 0 0 0
TP % Load Reduction 20.6222 42.6231 11.6037 15.2784
TN Flow In (kg/yr) 19.3417 16.8369 16.0675 18.3244
TN ET Loss (kg/yr) 0 0 0 0
TN Infiltration Loss (kg/yr) 0 0 0 0
TN Low Flow Bypass Out (kg/yr) 0 0 5.68879 6.00663
TN High Flow Bypass Out (kg/yr) 0 0 0 0
TN Orifice / Filter Out (kg/yr) 15.7985 2.69899 7.19625 0.637974
TN Weir Out (kg/yr) 0 5.59682 2.20588 9.42216
TN Transfer Function Out (kg/yr) 0 0 0 0
TN Reuse Supplied (kg/yr) 2.06766 0 0 0
TN Reuse Requested (kg/yr) 0 0 0 0
TN % Reuse Demand Met 0 0 0 0
TN % Load Reduction 18.3188 50.7283 6.07767 12.3205
GP Flow In (kg/yr) 139.657 21.4733 10.3267 18.4554
GP ET Loss (kg/yr) 0 0 0 0
GP Infiltration Loss (kg/yr) 0 0 0 0
GP Low Flow Bypass Out (kg/yr) 0 0 8.84656 10.3269
GP High Flow Bypass Out (kg/yr) 0 0 0 0
GP Orifice / Filter Out (kg/yr) 0 0 0 0
GP Weir Out (kg/yr) 0 0 0 0
GP Transfer Function Out (kg/yr) 0 0 0 0
GP Reuse Supplied (kg/yr) 0 0 0 0
GP Reuse Requested (kg/yr) 0 0 0 0
GP % Reuse Demand Met 0 0 0 0
GP % Load Reduction 100 100 14.3333 44.0439
PET Scaling Factor 1 1
No Generic treatment nodes
Other nodes
Receiving Node -
Location Tributary
ID 8
Node Type ReceivingNode
IN - Mean Annual Flow (ML/yr) 6.46
IN - TSS Mean Annual Load (kg/yr) 103
IN - TP Mean Annual Load (kg/yr) 0.815
IN - TN Mean Annual Load (kg/yr) 8.3
IN - Gross Pollutant Mean Annual Load (kg/yr) 0
OUT - Mean Annual Flow (ML/yr) 6.46
OUT - TSS Mean Annual Load (kg/yr) 103
OUT - TP Mean Annual Load (kg/yr) 0.815
OUT - TN Mean Annual Load (kg/yr) 8.3
OUT - Gross Pollutant Mean Annual Load (kg/yr) 0
% Load Reduction 12.6
TSS % Load Reduction 85.5
Page 23
TN % Load Reduction 64.9
TP % Load Reduction 59.1
GP % Load Reduction 100
Links
Location Drainage Link Drainage Link Drainage Link Drainage Link
Source node ID 1 6 2 3
Target node ID 2 4 7 7
Muskingum-Cunge Routing Not Routed Not Routed Not Routed Not Routed
Muskingum K
Muskingum theta
IN - Mean Annual Flow (ML/yr) 6.04 0.548 5.2 0.801
IN - TSS Mean Annual Load (kg/yr) 174 218 121 318
IN - TP Mean Annual Load (kg/yr) 1.07 0.372 0.846 0.555
IN - TN Mean Annual Load (kg/yr) 19.3 1.76 15.8 2.53
IN - Gross Pollutant Mean Annual Load (kg/yr) 140 12.6 0 18.5
OUT - Mean Annual Flow (ML/yr) 6.04 0.548 5.2 0.801
OUT - TSS Mean Annual Load (kg/yr) 174 218 121 318
OUT - TP Mean Annual Load (kg/yr) 1.07 0.372 0.846 0.555
OUT - TN Mean Annual Load (kg/yr) 19.3 1.76 15.8 2.53
OUT - Gross Pollutant Mean Annual Load (kg/yr) 140 12.6 0 18.5
Catchment Details
Kabara_MUSIC_12Ja
n2022_increasedtank
Catchment Name s
Timestep 6 Minutes
Start Date 1/01/1973
End Date 31/12/1983 23:54
Rainfall Station 40059 COOROY
User-defined monthly
ET Station PET
Mean Annual Rainfall (mm) 1595
Mean Annual ET (mm) 1631
Page 24
Drainage Link Drainage Link Drainage Link
5 7 4
4 5 8
Not Routed Not Routed Not Routed
5.96 5.96 6.46
250 324 103
1.05 1.19 0.815
15.1 16.1 8.3
8.85 10.3 0
5.96 5.96 6.46
250 324 103
1.05 1.19 0.815
15.1 16.1 8.3
8.85 10.3 0
[OCR of page images]
Drainage Link
5
4
Not Routed
5.96
250
1.05
15.1
8.85
5.96
250
1.05
15.1
8.85
Drainage Link
7
5
Not Routed
5.96
324
1.19
16.1
10.3
5.96
324
1.19
16.1
10.3
Drainage Link
4
8
Not Routed
6.46
103
0.815
8.3
6.46
103
0.815
8.3
Page 25
Callaghan & Toth
APPENDIX B: - Site Photos
Photo 1 – Biobasin completed in 2013
Photo 2 – Access Driveway
B
2160, Kabara Upgrade, Cooroy IWMP.doc January 2022
Page 26
Callaghan & Toth
APPENDIX C: - DETENTION BASIN RESULTS
C
2160, Kabara Upgrade, Cooroy IWMP.doc January 2022
Page 27
PRE DEVELOPMENT noosa 10-Year Duration=6 min, Inten=203.1 mm/hr
Prepared by HP Inc. Printed 20/01/2022
HydroCAD® 10.00-26 s/n 05328 © 2020 HydroCAD Software Solutions LLC Page 5
Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points
Runoff by Rational method, Rise/Fall=1.0/1.7 xTc
Reach routing by Stor-Ind method - Pond routing by Stor-Ind method
Subcatchment 1S: Existing Equivalent Runoff Area=586.0 m² 0.00% Impervious Runoff Depth=19 mm
Tc=6.0 min C=0.70 Runoff=0.02317 m³/s 0.011 Ml
Subcatchment 2S: Existing Runoff Area=2,000.0 m² 100.00% Impervious Runoff Depth=27 mm
Tc=6.0 min C=1.00 Runoff=0.11297 m³/s 0.055 Ml
Reach 4R: Creek Inflow=0.13614 m³/s 0.066 Ml
Outflow=0.13614 m³/s 0.066 Ml
Total Runoff Area = 0.2586 ha Runoff Volume = 0.066 Ml Average Runoff Depth = 26 mm
22.66% Pervious = 0.0586 ha 77.34% Impervious = 0.2000 ha
Page 28
PRE DEVELOPMENT noosa 100-Year Duration=6 min, Inten=295.9 mm/hr, Cf=1.20
Prepared by HP Inc. Printed 20/01/2022
HydroCAD® 10.00-26 s/n 05328 © 2020 HydroCAD Software Solutions LLC Page 5
Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points
Runoff by Rational method, Rise/Fall=1.0/1.7 xTc
Reach routing by Stor-Ind method - Pond routing by Stor-Ind method
Subcatchment 1S: Existing Equivalent Runoff Area=586.0 m² 0.00% Impervious Runoff Depth=34 mm
Tc=6.0 min Frequency Adjusted C=0.84 Runoff=0.04052 m³/s 0.020 Ml
Subcatchment 2S: Existing Runoff Area=2,000.0 m² 100.00% Impervious Runoff Depth=40 mm
Tc=6.0 min C=1.00 Runoff=0.16463 m³/s 0.080 Ml
Reach 4R: Creek Inflow=0.20514 m³/s 0.100 Ml
Outflow=0.20514 m³/s 0.100 Ml
Total Runoff Area = 0.2586 ha Runoff Volume = 0.100 Ml Average Runoff Depth = 39 mm
22.66% Pervious = 0.0586 ha 77.34% Impervious = 0.2000 ha
Page 29
POST DEVELOPMENT noosa 10-Year Duration=6 min, Inten=203.1 mm/hr
Prepared by HP Inc. Printed 21/01/2022
HydroCAD® 10.00-26 s/n 05328 © 2020 HydroCAD Software Solutions LLC Page 6
Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points
Runoff by Rational method, Rise/Fall=1.0/1.7 xTc
Reach routing by Muskingum-Cunge method - Pond routing by Stor-Ind method
Subcatchment 2S: New Roof - West Runoff Area=1,269.0 m² 100.00% Impervious Runoff Depth=27 mm
Tc=6.0 min C=1.00 Runoff=0.07168 m³/s 0.035 Ml
Subcatchment 4S: New Equivalent Runoff Area=20.5 m² 0.00% Impervious Runoff Depth=19 mm
Tc=6.0 min C=0.70 Runoff=0.00081 m³/s 0.000 Ml
Subcatchment 6S: New Equivalent Runoff Area=21.5 m² 0.00% Impervious Runoff Depth=19 mm
Tc=6.0 min C=0.70 Runoff=0.00085 m³/s 0.000 Ml
Subcatchment 7S: New Roof - East Runoff Area=1,275.0 m² 100.00% Impervious Runoff Depth=27 mm
Tc=6.0 min C=1.00 Runoff=0.07202 m³/s 0.035 Ml
Reach 4R: Creek Inflow=0.13354 m³/s 0.071 Ml
Outflow=0.13354 m³/s 0.071 Ml
Pond 1P: 4,000L Slimline Tank - Peak Elev=108.959 m Storage=3.8 m³ Inflow=0.04900 m³/s 0.031 Ml
132 mm Round Culvert n=0.010 L=2.00 m S=0.6250 m/m Outflow=0.04732 m³/s 0.031 Ml
Pond 8P: 4,000L Slimline Tank - Peak Elev=108.961 m Storage=3.8 m³ Inflow=0.04900 m³/s 0.032 Ml
132 mm Round Culvert n=0.010 L=10.00 m S=0.0700 m/m Outflow=0.04734 m³/s 0.032 Ml
Link 3L: (new Link) below 0.04900 m³/s Inflow=0.07249 m³/s 0.035 Ml
Primary=0.04900 m³/s 0.031 Ml Secondary=0.02349 m³/s 0.004 Ml
Link 5L: (new Link) below 0.04900 m³/s Inflow=0.07287 m³/s 0.035 Ml
Primary=0.04900 m³/s 0.032 Ml Secondary=0.02387 m³/s 0.004 Ml
Total Runoff Area = 0.2586 ha Runoff Volume = 0.071 Ml Average Runoff Depth = 27 mm
1.62% Pervious = 0.0042 ha 98.38% Impervious = 0.2544 ha
Page 30
POST DEVELOPMENT noosa 100-Year Duration=6 min, Inten=295.9 mm/hr, Cf=1.20
Prepared by HP Inc. Printed 21/01/2022
HydroCAD® 10.00-26 s/n 05328 © 2020 HydroCAD Software Solutions LLC Page 6
Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points
Runoff by Rational method, Rise/Fall=1.0/1.7 xTc
Reach routing by Muskingum-Cunge method - Pond routing by Stor-Ind method
Subcatchment 2S: New Roof - West Runoff Area=1,269.0 m² 100.00% Impervious Runoff Depth=40 mm
Tc=6.0 min C=1.00 Runoff=0.10446 m³/s 0.051 Ml
Subcatchment 4S: New Equivalent Runoff Area=20.5 m² 0.00% Impervious Runoff Depth=34 mm
Tc=6.0 min Frequency Adjusted C=0.84 Runoff=0.00142 m³/s 0.001 Ml
Subcatchment 6S: New Equivalent Runoff Area=21.5 m² 0.00% Impervious Runoff Depth=34 mm
Tc=6.0 min Frequency Adjusted C=0.84 Runoff=0.00149 m³/s 0.001 Ml
Subcatchment 7S: New Roof - East Runoff Area=1,275.0 m² 100.00% Impervious Runoff Depth=40 mm
Tc=6.0 min C=1.00 Runoff=0.10495 m³/s 0.051 Ml
Reach 4R: Creek Inflow=0.20421 m³/s 0.103 Ml
Outflow=0.20421 m³/s 0.103 Ml
Pond 1P: 4,000L Slimline Tank - Peak Elev=109.044 m Storage=4.0 m³ Inflow=0.04900 m³/s 0.037 Ml
132 mm Round Culvert n=0.010 L=2.00 m S=0.6250 m/m Outflow=0.04850 m³/s 0.037 Ml
Pond 8P: 4,000L Slimline Tank - Peak Elev=109.044 m Storage=4.0 m³ Inflow=0.04900 m³/s 0.037 Ml
132 mm Round Culvert n=0.010 L=10.00 m S=0.0700 m/m Outflow=0.04850 m³/s 0.037 Ml
Link 3L: (new Link) below 0.04900 m³/s Inflow=0.10587 m³/s 0.051 Ml
Primary=0.04900 m³/s 0.037 Ml Secondary=0.05687 m³/s 0.015 Ml
Link 5L: (new Link) below 0.04900 m³/s Inflow=0.10644 m³/s 0.052 Ml
Primary=0.04900 m³/s 0.037 Ml Secondary=0.05744 m³/s 0.015 Ml
Total Runoff Area = 0.2586 ha Runoff Volume = 0.103 Ml Average Runoff Depth = 40 mm
1.62% Pervious = 0.0042 ha 98.38% Impervious = 0.2544 ha