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Sydney Water Annual Report 2009
Sustainability indicators: Helping develop a water efficient city
 
Investment in recycled water schemes increased by 145%.
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In this section:

 

 
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Reuse and recycling
Performance: 10,014 million litres of drinking water saved through recycling schemes. Investment in recycled water schemes increased by 145%.

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Indicator: Total volume of water recycled on account of recycled water schemes managed by Sydney Water

Water reuse and recycling are important in securing Sydney’s water supply. Recycled water contributes to drinking water savings when it can be used in place of drinking water.

Sydney Water operates 16 recycled water schemes including the residential dual reticulation scheme at Rouse Hill, the Wollongong Recycled Water Scheme, which supplies recycled water for industrial and irrigation use, and other schemes that supply recycled water for use in agriculture and on playing fields and golf courses.

In 2008–09, Sydney Water recycled 25,442 million litres of wastewater, more than five per cent of total wastewater collected and an increase of 1,279 million litres on 2007–08. This was largely due to increased on-site recycling at Sydney Water’s sewage treatment plants (STPs).

By the end of June 2009, 18,500 residential properties were connected to stage one of the Rouse Hill recycling scheme. Over the past seven years, Rouse Hill customers have used 28% less drinking water than households without access to recycled water.

Stage one of the Wollongong Recycled Water Scheme used less water during the year, down from 6,652 million litres in 2007–08 to 4,398 million litres in 2008–09, due mainly to lower steel production as a result of the global economic downturn. Stage two of the Wollongong Recycled Water Scheme came online in April 2009, supplying recycled water to the Port Kembla Coal Terminal and Wollongong Golf Club.

Also included in the 2008–09 recycling figures are agricultural releases of 2,096 million litres from the West Camden STP. The plant is being upgraded as part of Sydney Water’s long-term water and wastewater strategy and will improve the quality of wastewater released into the Nepean River.

Under the 2006 Metropolitan Water Plan, the NSW Government has set a goal of recycling about 70 billion litres of wastewater a year by 2015 to meet 12% of Sydney’s water needs. To support this target, Sydney Water seeks to provide recycled water schemes where it is economically, technically and environmentally feasible to do so.

Construction of the Western Sydney Replacement Flows Project continued in 2008–09. The $250 million project is designed to save drinking water and maintain river health. It will increase the volume of recycled water used in Sydney by about 70%, from 25 billion litres a year to more than 40 billion litres a year. The project will connect the Penrith, St Marys and Quakers Hill STPs so that treated wastewater from all three plants can be piped to the new recycled water plant at St Marys for further treatment. It will release up to 18 billion litres of highly treated recycled water to the Hawkesbury-Nepean River system each year, replacing water currently released from Warragamba Dam to maintain environmental flows.

Additional drinking water savings of up to 4.3 billion litres a year will be achieved when the Camellia recycled water plant is completed. The plant is being constructed on the Fairfield storm STP site and will supply water for irrigation and for industrial customers in the Smithfield and Camellia areas. Construction started in June 2009 and is due to finish in 2011.

Construction of new dual reticulated schemes has begun at Hoxton Park, Ropes Crossing and Quakers Hill. There are currently 350 properties connected to these schemes. The first of these should have access to recycled water from 2013.

In 2008–09, 10,014 million litres of drinking water have been saved through recycling projects in the greater Sydney area. These include two private projects, the Sydney Olympic Park Authority’s Water Reclamation and Management System at Homebush and Orica’s project at Botany.

For more detail and comprehensive analysis, see Sydney Water’s Water Conservation and Recycling Implementation Report 2008–09.

Total volume of water recycled on account of recycled water schemes managed by Sydney Water

Note: The off-site (non-Sydney Water premises) figure does not include the Sydney Olympic Park Authority’s water recycling scheme and Orica’s recycling scheme at Botany.

 

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Water leakage
Performance: Leakage remained low at 7.3% of drinking water drawn. Sydney Water is on track to meet the target of 105 million litres a day by June 2010.

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Indicator: Water leakage expressed as a percentage of drinking water drawn

Water leakage is the difference between the amount of water supplied by filtration plants and the amount delivered to customers. Sydney Water uses the global water balance method recommended by the International Water Association to estimate leakage from its water supply systems. The methodology has an uncertainty band of ± 25% (95% confidence limit), which can result in fluctuations from year to year. It includes adjustments for uses such as fire fighting, system maintenance and losses due to illegal water use.

Water leakage during 2008–09 was an estimated 38.4 billion litres, or 105 million litres a day. This is about 7.3% of total drinking water drawn, which is the lowest result on record. Over the past six years, leakage has fallen by about 83 million litres a day, from 188 million litres a day to an estimated 105 million litres a day. This result is in line with Sydney Water’s Operating Licence target of reducing leakage to 105 million litres a day by 30 June 2009.

In 2008–09, the Independent Pricing and Regulatory Tribunal (IPART) and Sydney Water agreed that compliance with the Operating Licence target would be based upon the leakage result for 2009–10, rather than 2008–09. IPART recognises the difficulties in accurately measuring leakage and will deem Sydney Water compliant if the target of 105 million litres is within one standard deviation from the estimated leakage results.

Based upon the result for 2008–09 and the forecast gains from leakage programs, Sydney Water expects to comply with the licence target when the IPART method is applied to the 2009–10 year.

Leakage from the water network is affected by demand and by the number of inspections and repairs carried out. The reduction in leakage since 2002–03 is mainly due to the Active Leak Detection Program, which uses acoustic and electronic equipment to scan the water network and identify hidden leaks for repair. The remaining savings were due to:

  • faster repairs of leaks reported by customers
  • the Pressure Management Program, which aims to maintain a more consistent pressure in the network to reduce breaks and leaks
  • better accounting using the global water balance methodology.

Further large reductions from the Active Leak Detection Program are unlikely. The program will aim to maintain the significant gains already achieved. Other programs underway that will contribute small short-term leakage savings and improve monitoring of leaks include the Trunk Main Leak Detection and Bulk Flow Meter Installation programs. The latter project involves installing and renewing flow meters to quickly detect leaks and measure leak reductions following repairs.

Water leakage expressed as a percentage of drinking water drawn

Note: In 2006–07, Sydney Water adopted the Water Services Association of Australia (WSAA) default value of two per cent for customer meter under-registration. The 2005–06 reported figure of 8.5% has been adjusted to 8.1% as a result. Figures since 2005–06 are based on the water drawn in the base year 2005–06.

 

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Demand management
Performance: Investment in demand management and water savings have increased significantly since the programs began in 1999. Water savings increased by almost 13% compared to 2007–08.

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Indicator: Total volume of drinking water saved on account of demand management programs

Sydney Water encourages residential, commercial and industrial customers to use less water. Its water conservation strategy includes demand management, leak reduction and recycling programs.

During 2008–09, more than $75 million were spent on water conservation programs, and customers made significant efforts to use water more efficiently. This increased water savings by almost 13% (9,685 million litres) compared to 2007–08 and brought total savings for 2008–09 to 85,848 million litres. Initiatives that contributed to the savings included:

  • regulatory measures (Water Efficiency Labelling Standards and the Building Sustainability Index)
  • recycled water projects
  • leak reduction programs
  • business programs, including Every Drop Counts and Smart Rinse
  • outdoor residential programs, including Love Your Garden and rainwater tank rebates
  • indoor residential programs, including WaterFix, DIY Water Saving Kits, washing machine rebates and the toilet replacement service.

For a full review of Sydney Water’s water conservation activities and initiatives, please see the Water Conservation and Recycling Implementation Report 2008–09.

Total volume of drinking water saved per year on a ccount of demand management programs

 

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Water drawn
Performance: The total volume of water drawn increased slightly due to a return to average weather conditions in 2008–09.

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Indicator: Total volume of water drawn by Sydney Water from all sources

The amount of drinking water available to be drawn each year from Sydney’s supply system is estimated to be 570 billion litres (supply system yield) excluding water from the desalination plant still under construction.

Almost 492 billion litres (491,962 million litres) were drawn for supply to customers in 2008–09, which was two per cent more than in 2007–08. The increase in demand was mainly due to a return to average weather conditions in 2008–09 compared to the relatively wet and cool conditions in 2007–08.

The lower volumes of water drawn in 1995–96 and 1996–97 and from 2003–04 to 2007–08 reflect the effect of water restrictions (from 1 November 1994 to 16 October 1996, and 1 October 2003 to June 2009). Weather had a greater effect on demand than restrictions in 2008–09.

Dam levels are updated each week on the Sydney Catchment Authority website at www.sca.nsw.gov.au.

Total volume of water drawn by Sydney Water from all sources

Indicator: Water drawn expressed on a per capita basis

Sydney Water’s Operating Licence requires that drinking water demand be reduced to 329 litres a person a day by 2010–11, a 35% reduction from the 1991 baseline. Based on current population estimates, this per person target equals a total reduction of almost 531,105 million litres a year by June 2011.

In 2008–09, total demand was 309 litres a person a day, up from 306 litres in 2007–08. This figure includes savings from water restrictions. After climate correction, demand was 310 litres a person a day. Climate correction accounts for weather conditions that vary significantly from the average to show where demand would have been in average conditions. It also includes the savings gained from mandatory water restrictions. Sydney Water has estimated that without restrictions, demand would have been 372 litres a person a day, down from 378 litres a day in 2007–08 and 389 litres a day in 2006–07.

Per capita demand trended down between 2002–03 and 2007–08, primarily due to water restrictions. Savings from water efficiency initiatives along with increased rainfall and lower temperatures helped reduce per capita water demand, especially in 2006–07 and 2007–08. The increase in potable water drawn in 2008–09 was due to a return to average weather conditions after a relatively wet, cool year. It is expected that Sydney Water will meet its 2011 water conservation target of 329 litres a person a day.

Water drawn expressed on a per capita basis