Across Australia and around the world, water utilities are facing a complex challenge: meeting the needs of growing populations while simultaneously pursuing better outcomes across performance, efficiency, sustainability and community.
In the city of Murray Bridge, 80 kilometres east of Adelaide, SA Water’s wastewater treatment plant served the local community for around five decades, and during this time the population and needs of residents and business changed significantly. A new wastewater treatment plant would ensure local operations could continue to sustain community growth and activity.
A $52-million upgrade to Murray Bridge’s sewerage network – which included the construction of a new treatment plant, four pump stations and the installation of around 18 kilometres of new underground sewer mains – began in late 2018. The plant and supporting infrastructure became fully operational in mid-2020.
SA Water contracted John Holland to lead the construction, bringing SUEZ – a partner of SA Water through the metropolitan alliance – into the design and build partnership.
SA Water’s former wastewater treatment plant at Murray Bridge had capacity to treat around 2.6 million litres of sewage a day, with 100 per cent recycled for irrigation use in surrounding properties. The new Murray Bridge Wastewater Treatment Plant (WWTP) boosts capacity by nearly two million litres, to 4.5 million litres a day, enabling it to accommodate expected future growth in population and industry.
With the original plant situated on the Murray River floodplain, moving the facility to Brinkley, around 10 kilometres south of the Murray Bridge township, also improves its environmental performance by eliminating a source of odour and the potential for discharge into the river during high flood events.
SUEZ’s Meteor™ Moving Bed Biofilm Reactor (Meteor™ – MBBR) underpins the new Murray Bridge WWTP’s design. The compact biological process breaks sewage down into sludge more efficiently and effectively than traditional space-intensive solutions.
Downstream from this, SUEZ’s Densadeg® compact high-rate lamella clarification system separates suspended solids from the treated wastewater, taking it through the stages of coagulation/flocculation, water clarification and settling of sludge.
While SUEZ has successfully deployed these technologies in hundreds of locations around the world, this is the first time the two have been combined in a municipal wastewater treatment plant. Together, they make Murray Bridge WWTP one of the world’s most cost-efficient and sustainable municipal treatment plants of comparable capacity.
The plant also features an odour control unit consisting of a bio-trickling filter and activated carbon tanks, effectively removing 99.5 per cent of odour.
It’s vital our wastewater infrastructure is able to operate with minimal environmental impact and in a cost-effective manner. Our new Murray Bridge Wastewater Treatment Plant fulfils these objectives, while meeting the needs of the local community now and into the future, as well as the requirements of South Australia’s environmental regulator.
Chas Allen , SA Water Project Manger
Like its predecessor, the new Murray Bridge WWTP recycles 100 per cent of the treated wastewater for irrigation use on the adjacent Department of Defence and pastoral land – only in much greater quantities as input volumes grow.
After being fully broken down through SUEZ’s advanced technologies and processes, the resulting sludge is transformed into organic biosolids, able to be used like a compost to improve soils and selected crops.
The onsite solar array built into the plant will also ultimately generate 150 kilowatt hours per day to help power its operations.
In July 2020, the Infrastructure Sustainability Council of Australia awarded the new Murray Bridge WWTP an ‘excellent’ design rating – the highest to date for an Australian water or wastewater project.