Report No S.TCG-0107.ESD.R04.02 engineering sustainable environments Date 17th October 2017
WATER MANAGEMENT STRATEGY
PROPOSED INDUSTRIAL DEVELOPMENT
BUILDING 4, 2 HUME HIGHWAY, CHULLORA
Prepared For and On Behalf of:
Water Management Strategy Report Authorisation
UMOW LAI i S.TCG-0107.ESD.R04.02
REPORT AUTHORISATION
PROJECT: Building 4, 2 Hume Highway, Chullora
REPORT NO.: S.TCG-0107.ESD.R04.02
DATE REV COMMENT PREPARED
BY CHECKED BY
AUTHORISED BY
17/10/2017 01 Preliminary issue NJM PTJ PTJ
15/11/2017 02 FINAL issue NUM PTJ PTJ
This document contains commercial information which has been prepared for the attention of the Client on this project. It is confidential and no information contained in this document shall be released in part or whole to any third party without the approval of Umow Lai.
Melbourne Office 10 Yarra Street
South Yarra VIC 3141 Australia
Tel: +61 3 9249 0288 Fax: + 61 3 9249 0299
Email: [email protected] Web: www.umowlai.com.au
ABN: 29 143 564 738
Sydney Office L7, 657 Pacific Highway St Leonards NSW 2065
Australia Tel: +61 2 9431 9431 Fax: +61 2 9437 3120
Email: [email protected] Web: www.umowlai.com.au
ABN: 80 143 565 324
Brisbane Office 123 Charlotte Street Brisbane QLD 4000
Australia Tel: +61 7 3210 1800 Fax: +61 7 3210 1799
Email: [email protected] Web: www.umowlai.com.au
ABN: 91 142 668 773
Water Management Strategy Executive Summary
UMOW LAI iii S.TCG-0107.ESD.R04.02
EXECUTIVE SUMMARY
Umow Lai have been engaged to prepare a Water Cycle Management Strategy on behalf of Taylor Construction Group to address the following Bankstown City Council Development Control Plan (DCP) requirements for the Proposed Industrial Development (Building 4) located at 2 Hume Highway, Chullora, NSW.
This report addresses the following issues relating to Water:
• Preparation of an integrated water collection and recycling system for the capturing and recycling of rainwater; and
• Proposals for controlling the quality of waste water that is to be disposed of.
The use of water sensitive urban design principles including the collection and reuse of rainwater, and the use of water efficient fixtures will result in a reduction in the potable water demand of the development relative to a comparable benchmark.
Careful consideration has been given to the use of appropriately sourced potable and non potable water supply streams supplying the various end uses.
We would recommend that the proposed water management measures are in accordance with the current regulatory requirements and that the scheme should be adopted as an acceptable method of addressing the water management issues relevant to the site.
Water Management Strategy Contents
UMOW LAI v S.TCG-0107.ESD.R04.02
CONTENTS
1.0 REPORT OBJECTIVE 1
2.0 SITE DESCRIPTION 2
3.0 WATER DEMAND 6
4.0 DEMAND REDUCTION 8
5.0 SITE WATER BALANCE 10
6.0 STORMWATER 12
7.0 SUMMARY AND RECOMMENDATIONS 13
Water Management Strategy Report Objective
UMOW LAI 1 S.TCG-0107.ESD.R04.02
1.0 REPORT OBJECTIVE
The aim of this report is to outline the strategy for water management for the Proposed Industrial Development (Building 4) located at 2 Hume Highway, Chullora, NSW.
This water management strategy has been prepared to identify;
• Site conditions and available infrastructure;
• Site water demands;
• Available sources of potable and non potable water;
• Water efficiency measures, including a practical water management strategy for the site; and
• Waste water discharge.
The water management strategy has been prepared in consideration of relevant Sydney Water and local authority requirements.
This report should be read in conjunction with the following documents:
• Drawings - Architectural
- 2523981-L4-DA-301 Rev D Ground Floor Plan - 2523981-L4-DA-101 Rev E Site and Roof Plan - 2523981-GA-DA-002 Rev C Master Site Context Plan
• Report - Civil Works
- Co12891.06-01 Civil Engineering Report for Development Application
• Charter Hall Design Brief Outline Revision B
Water Management Strategy Site Description
UMOW LAI 2 S.TCG-0107.ESD.R04.02
2.0 SITE DESCRIPTION
The site comprises the former part of Fairfax Limited printing facility which is now partly demolished as part of new works on Lots 2 and 3. The larger site is bounded by Worth Street to the North & West and Beaufort Place, with an Australia Post mail facility to the South East. Existing industrial development is located to the North/West of Worth Street and East of the Hume Highway. Building 4 is located within the South West corner of the site.
The site is approximately 15km west of the Sydney CBD and provides access to both the M4 and M5 motorways.
Figure 1 Existing Site Plan
Water Management Strategy Site Description
UMOW LAI 3 S.TCG-0107.ESD.R04.02
2.1 PROPOSED DEVELOPMENT
The proposed development comprises of two large single level warehouses (4A & 4B) with associated office spaces (one level), and parking provisions. Access is made from Worth Street.
Figure 2 Proposed Site Plan
2.2 AREAS AND OCCUPANCY
The following tables provide a summary of Warehouse Building 4A and Warehouse Building 4B within the site.
Description Area (m2) Occupancy Estimate
Operational Profile
Warehouse 5,000 10 10hrs, 5 days
Office/Amenities 300 10 10hrs, 5 days
TOTAL 20
Table 1 Warehouse Building 4A - Areas and Profiles
Water Management Strategy Site Description
UMOW LAI 4 S.TCG-0107.ESD.R04.02
Description Area (m2) Occupancy Estimate
Operational Profile
Warehouse 6,940 10 10hrs, 5 days
Office/Amenities 250 9 10hrs, 5 days
TOTAL 19
Table 2 Warehouse Building 4B - Areas and Profiles
2.3 WATER INFRASTRUCTURE
Existing water infrastructure in the area consists of:
• 450mm diameter Ductile Iron Cement (mortar) Lined (DICL) water main running from the Hume Highway intersection along the southern side of Worth Street. This reduces to a 250mm DICL water main opposite the entrance to the recycling plant on Worth Street.
• 600mm diameter Cast Iron Cement Lined water main running down the centre of the Hume Highway. Not suitable for connection.
• 2475mm diameter Steel Cement Lined Internal Bitumen Lined (SCL IBL) recycled water main. Expected to be very deep (>10m) and not expected to create an issue for future development.
The site is supplied via a 100mm connection, located at the current vehicular entrance from the 450mm diameter DICL water main in Worth Street and it is assumed that this connection will be utilised.
There is a water tank and pump house to the west of the site and this provides a supply for the existing fire hydrant system. As this will be removed to accommodate new buildings, an alternative similar fire supply infrastructure will be required.
Figure 3 Dial Before You Dig – Sydney Water Authority
Water Management Strategy Site Description
UMOW LAI 5 S.TCG-0107.ESD.R04.02
2.4 SEWER INFRASTRUCTURE
Existing sewer infrastructure in the area consists of:
• 600mm diameter concrete encased sewer with an existing easement crosses the site from the Hume Highway to Worth Street, running through the end of Beaufort Place. Not suitable for connection.
• 225mm diameter vitrified clay within the property boundary running parallel to the Hume Highway.
The 225mm diameter vitrified clay sewer located on the south east boundary is suitable for connection.
Water Management Strategy Water Demand
UMOW LAI 6 S.TCG-0107.ESD.R04.02
3.0 WATER DEMAND
3.1 SITE WATER DEMAND ASSESSMENT
The following water demands suitable for the development have been considered for the proposed facility:
• Staff and administration; kitchen, staff change room toilets and ablutions;
• Heating ventilation and air conditioning demand;
• Fire systems testing water;
• Washdown; and
• Landscape irrigation.
3.2 AMENITIES
It has been assumed that all fixtures and fittings will be specified to comply with watermark licence and be Water Efficiency Labelling Scheme (WELS) rated.
Description WELS rating Water Efficiency
WC’s 4 star 4.5L full 3.0L half/flush
Urinals 3 star 1.8 L/flush
Basins Taps 6 star 6.0 L/m
Showers 3 star 9 L/m
Dishwashers (10pl) 3 star 15 L/cycle
Table 3 Fixtures and Fittings Schedule
The following assumptions have been made
• Four visits to the WC a day
- 60/40 male/female split - 3:1 ratio for male urinal visits - 10 second hand washing
• 4 showers - used by 2.5% staff, once a day
• 1 dishwasher within main office space used once a day (230 work days per year)
3.3 HVAC DEMANDS
For the purpose of this report we have assumed the following:
• The warehouse area is naturally ventilated with mechanical exhaust for potential smoke and exhaust;
• Office/Showroom areas are air conditioned with no water-based heat rejection (i.e. air-cooled chillers or VRV DX systems).
Based on the above scenario the HVAC system will make no demand on water infrastructure.
Water Management Strategy Water Demand
UMOW LAI 7 S.TCG-0107.ESD.R04.02
3.4 FIRE WATER
A fire water tank will be provided to the site. Sprinklers will be served via the fire tank Fire test water will be utilised recirculated from the sprinkler tank, making no demand on infrastructure. Minor losses will be incurred from sprinkler zone testing.
3.5 WASHDOWN
Washdown is assumed to be provided from non-potable (rainwater) sources. General assumptions are made regarding the daily demand for washdown purposes.
3.6 IRRIGATION
The development will feature approximately 2,930m2 of landscaping to the site boundary and within the car park. Landscaping shall be selected with plant species that require minimal water and irrigating with appropriate systems to minimize water loss and evaporation. This includes using native plant species, using mulch deeply around garden beds, avoiding watering when it’s windy, watering during the coolest parts of the day and using a drip irrigation system with rain sensors. An allowance of 300sqm of drip fed irrigation has been made for new plantings.
Water Management Strategy Demand Reduction
UMOW LAI 8 S.TCG-0107.ESD.R04.02
4.0 DEMAND REDUCTION
Reducing water consumption is a simple and easy way to reduce the developments impact on the environment, while reducing the operational water cost.
4.1 FIXTURE AND FITTINGS
The use of efficient fixtures and fittings, including toilets, urinals, taps, showers and appliances can have a significant impact on the quantity of water required. Where possible fitting selections should be of the highest WELS ratings.
As a minimum, the following selections shall be met:
Description WELS rating Water Efficiency
WC’s 4 star 4.5L full 3.0L half/flush
Urinals 3 star 1.8 L/flush
Basins Taps 6 star 6.0 L/m
Showers 3 star 9 L/m
Dishwashers (10pl) 3 star 15 L/cycle
Table 4 Fixtures and Fittings Schedule
4.2 RAINWATER HARVESTING, STORAGE AND REUSE
Rainwater harvesting involves the collection, storage and re-use of rainwater from the roof areas of a development for internal and external uses. In relation to the proposed development site, harvested rainwater could potentially be used for toilet and urinal flushing and irrigation of landscaped areas.
Rainwater harvesting contributes to the conservation of drinking quality water, improves the reliability of our water supplies, frees up water for the environment and reduces the potential export of pollutants into the natural environment downstream.
The following measures will need to be adhered to with respect to the rainwater tank installation:
• Tanks to be installed and maintained to prevent cross connection with the potable mains water supply, including provision of a backflow prevention device at water meters;
• Provision of a low-level potable water top-up switch or tank bypass facility to ensure continual supply during drier periods;
• All rainwater services to be clearly labelled “Non-Potable Water” with appropriate hazard identification;
• Pipe work used for rainwater services to be coloured lilac in accordance with AS1345. All valves and apertures to be clearly and permanently labelled with safety signs to comply with AS1319.
It is assumed that rainwater will be collected from a portion of the warehouse roofs as dictated by the stormwater and drainage design. A roof co-efficient of 0.8 has been allowed for a flat roof collection area. Harvested rainwater will be utilised for toilet and urinal flushing and irrigation requirements.
Water Management Strategy Demand Reduction
UMOW LAI 9 S.TCG-0107.ESD.R04.02
4.3 GREY WATER, BLACK WATER & STORMWATER COLLECTION AND REUSE
Grey Water, Black Water and Stormwater collection and reuse are not proposed for this development.
Water Management Strategy Site Water Balance
UMOW LAI 10 S.TCG-0107.ESD.R04.02
5.0 SITE WATER BALANCE
Calculations have been undertaken to assess a suitable volume of rainwater storage to adequately meet the projected non potable water demand. Water balance modelling has been conducted using the Green Building Council of Australia’s “Potable Water Calculator”.
The calculations assume the roof rainwater catchment area to be 25% of available warehouse roof area (2,985 m2) and the total rainwater tank volume of 20 kL, serving both Warehouse Building 4A and Warehouse Building 4B.
The water balance modelled daily rainfall vs. consumption utilising over ten years of daily rainfall data supplied from the Bureau of Meteorology (BOM). Data sourced from the BOM station;
Strathfield Golf Club (2.0 km away)
Number: 66070
Lat: 33.89° S
Lon: 151.07° E
Elevation: 21 m
5.1 WATER BALANCE ASSESSMENT
The water demands best suited to rainwater supply include toilet and urinal flushing, and landscape irrigation. A further breakdown of the site water demand assessment follows, noting the resulting potable and non-potable demands.
Month Total Water
Demand (kL/month)
Rainwater Supply (kL/month)
Potable Supply (kL/month)
Percentage Reduction
January 170.6 15.5 155.0 9%
February 141.0 59.9 81.1 42%
March 141.9 98.5 43.4 69%
April 143.1 83.0 60.0 58%
May 147.0 22.4 124.6 15%
June 136.0 57.6 78.4 42%
July 144.2 23.0 121.2 16%
August 140.5 86.1 54.5 61%
September 141.6 76.5 65.1 54%
October 140.5 33.3 107.2 24%
November 156.0 70.7 85.2 45%
December 140.5 97.7 42.8 70%
TOTAL 1742.6 724.1 1018.5 42%
Table 5 Average Water Balance
Water Management Strategy Site Water Balance
UMOW LAI 11 S.TCG-0107.ESD.R04.02
Figure 4 Typical Monthly Potable vs Non Potable Water Consumption
.
Water Management Strategy Stormwater
UMOW LAI 12 S.TCG-0107.ESD.R04.02
6.0 STORMWATER
The design has been developed to incorporate the principles of Water Sensitive Urban Design (WSUD) and to minimise the impacts pollutants could have on receiving water ways.
6.1 STORMWATER TREATMENT SYSTEM
Per the civil engineering report, A civil engineering strategy for the site has been developed which provides a best practice solution within the constraints of the existing landform and proposed development layout. Within this strategy a stormwater quantity and quality management strategy has been developed to reduce both peak flows and pollutant loads in stormwater leaving this site. The stormwater management for the development has been designed in accordance with Bankstown City Council’s Development Engineering Standards 2009 and Engineering and Drainage Standards Policy 2005.
The hydrological assessment proves local post development flows from the site will be less than pre-development flows and demonstrates that the site discharge will not adversely affect any land, drainage system or watercourse as a result of the development.
Please refer to the civil report prepared by Constin Roe Consulting for full details of stormwater infrastructure (Report Co12891.06-01).
6.2 DURING CONSTRUCTION
During the construction phase, a Sediment and Erosion Control Plan will be in place to ensure the downstream drainage system and receiving waters are protected from sediment laden runoff.
Water Management Strategy Summary and Recommendations
UMOW LAI 13 S.TCG-0107.ESD.R04.02
7.0 SUMMARY AND RECOMMENDATIONS
The report addresses the water management requirements of the proposed development.
The major water management results and recommendations for the proposed development are as follows:
• Efficient fixtures and fittings will be installed throughout the facility to minimise site water consumption
• A rainwater harvesting system with a 20kL rainwater collection tank will be provided for the site. Due to the large catchment area, the rainwater harvesting system will provide a significant contribution to the non potable water demands for the site
• Water demand and discharge for the site is generally consistent throughout the year, due to the nature of the site.
We recommend that the design philosophy detailed in this report be accepted as an appropriate approach to addressing the water management issues relevant to the proposed development.