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Key departmental publications, e.g. annual reports, budget papers and program guidelines are available in our online archive.

Much of the material listed on these archived web pages has been superseded, or served a particular purpose at a particular time. It may contain references to activities or policies that have no current application. Many archived documents may link to web pages that have moved or no longer exist, or may refer to other documents that are no longer available.

Coca-Cola Amatil (NSW) Pty Ltd
Cleaner Production - Recovery and Reuse of Filter Backwash Water


The Coca Cola Amatil (CCA) Northmead plant in Sydney was established in 1972 and manufactures a wide range of world recognised Coca-Cola trademark soft drink products, such as Sprite, Fanta, Lift and Coca-Cola.

The Northmead plant has one aluminium can line and two plastic PET bottle lines. 

Pre-excisting Process

The manufacture of soft drinks requires large volumes of water. The water is treated on-site to meet product quality requirements before being used in the production process.

The Northmead plant treats an average of 1.5 million litres of municipal water daily using a conventional flocculation plant. This can operate at a rate of 200,000 litres per hour (using one older water treatment plant at 100,000 litre/hour and one newer water treatment plant at 100,000 litres/hour). Three types of filters are used - sand, carbon and polishing filters.

The company cleans the 10 sand and carbon filters on a daily basis by forcing water back through the filter - a process known as back washing. The new water treatment line allows for the back washing process to incorporate air (known as air sparging) to reduce the amount of water required.

The generation of backwash water is dependent on production levels, but is estimated to reach up to 200 kilolitres a day. The backwash water is disposed to the sewer.

Cleaner Production Initiatives

The cleaner production initiative that CCA implemented involved recycling the backwash water through the treatment plant, allowing it to be reused in the manufacturing process. The recycled water must meet strict quality standards, and can only be used in the ratio of 10-20% with non-recycled water to ensure that there is no compromise in final product quality.

Backwash Recovery Tank

Backwash recovery

Efforts are also being made to reduce the amount of material that contributes to the high BOD (biochemical oxygen demand) levels entering the effluent system. This includes the addition of a PIG (pipe cleaning system) that physically forces residual syrup out of the pipework and into the production process, thus reducing the amount that is discharged to sewer during cleaning. This will result in cost savings from reduced syrup wastage, and reduced trade waste fees.

Advantages of the Process

The installation of a backwash recovery tank, pipework and additional filter was $150,000. This compares with the annual savings of $100,000 from reduced municipal water consumption.

The initiative has also resulted in a 25 per cent reduction in trade waste discharged to sewer. Now the only source of wastewater generation is from equipment cleaning.

Under current trade waste regulations the trade waste discharge agreement is based on the concentration of the waste, not the total load. Such a significant reduction in the volume of essentially clean water going into the trade waste system has resulted in an increase in the contaminant concentration levels - particularly for BOD. This will mean that until the trade waste agreement is reviewed, the Northmead plant will be charged an increased amount to dispose of its trade waste, i.e. an estimated $15,000-20,000 per annum.  Load based licensing will be introduced on 1 July 2001, enabling CCA to realise the full financial benefit of the initiative.

Economic Benefits

Costs - Capital costs for backwash recycling initiative


Costs - Increased trade waste charges

$15,000-20,000 pa.


$100,000 pa


~ 2 years


The backwash system was included in CCA's plant upgrade as the company realised there was a cost effective opportunity to reduce municipal water consumption, and costs, with a consequent reduction in trade waste volumes.


The opportunity for water backwash recycling was recognised some years ago, however the strict global quality guidelines issued by The Coca-Cola Company prevented the development of this system. Also the high initial capital cost could not be justified in the past. Increased production levels have required a number of upgrades to the capacity of the water treatment plant, to a point where recovery and recycling of the backwash could be justified.

Further Developments

Water recycling continues to be critical to the water management of CCA's Northmead plant. Increases in sewer charges fees to around 85c/kL has meant even bigger cost benefits for the company from the initial initiative, in addition to the savings in water consumption costs.

A new water recycling initiative was introduced in 2001. Pipework modifications were made to the process rinse cycle prior to filling containers to enable capture of the container rinsing water. This water is then filtered and used in the evaporative cooling towers. This water recycling practice avoids the purchase and discharge of 6 million litres of water a year. The investment cost to make the changes was $6,000. $15,000 is saved annually in discharge charges.

Another initiative was implemented in mid 2000 when the company installed a lighting management system aligned with the production program whereby lights in sections of the line not in use are turned off. At the time of implementation, it was anticipated that this lighting change would result in a 5% overall reduction in electricity usage.

Other cleaner production initiatives adopted include bulk purchasing and recycling initiatives.

The site will be audited for ISO 14001 certification of their environmental management system in June 2001.


Kevin Tallentire
Environmental Coordinator
Coca-Cola Amatil Australia Pty Ltd
128 Briens Road
Ph: 02 8839 2395
Fax: 02 9683 6560

Implementation: 1997
Further initiatives: 2000, 2001
Case study initially prepared: June 1997 by Australian Centre for Cleaner Production


Last modified: May 2001