Upgrade works at Coliban Water are replacing the filtration membranes at both the Bendigo and Kyneton Water Treatment Plants.
Manager Community Operations, Mick Dunne, said the upgrades were needed to maintain a high standard of water quality to Bendigo and Kyneton customers.
“We replace the membranes every five to ten years, depending on their condition. The membranes were last changed at our Bendigo plant in 2010,” Mr Dunne said.
“It is a complex procedure to replace the membranes as the work needs to be carried out while the plant is in operation.”
The Bendigo plant has 4608 membranes, which take around eight weeks to replace. Coliban Water has taken a staged approach and replaced half of them throughout 2018 at a cost of $2.5 million, with the other half set to be replaced in 2019.
“Fluctuations in the raw water quality we source from the Waranga Channel via the Goldfields Superpipe has meant an increase in the frequency of the membrane cleaning process,” Mr Dunne said.
“After a period of time membranes accumulate particles that cannot be removed by cleaning. In addition their hollow microfiltration fibres can break over time affecting their integrity.
“Our Bendigo plant has the capacity to treat 126 megalitres of water per day and at the time of construction in 2002, was the largest water treatment plant in the world to use the submerged microfiltration technology.
“The new membranes will improve plant efficiency.”
The upgrade works are part of the AQUA Build Own Operate Transfer (BOOT) contract between Coliban Water and Bendigo Water Services (BWS), which is part of Veolia.
Veolia owns and operates water treatment plants for Bendigo, Castlemaine and Kyneton under a 25-year contract that started in June 2002.
The works to replace the 288 membranes at the Kyneton Water Treatment Plant took place in June 2018 and took three days to complete at a cost of around $300,000.
The Castlemaine Water Treatment Plant had its 630 filter membranes replaced over two years in 2016 and 2017 at a cost of around $700,000.