Upgrade wastewater recycling system

Low-impact and reliable technology required

Situated on Mt Tamborine in the Scenic Rim Region, Gallery Walk is one of the premier arts and craft centres of south-east Queensland. The collection of galleries and craft shops attracts hundreds of visitors each and every week.

The single public toilet block servicing the area had been served for the last eight years by a sand filter treatment system, the performance of which over time had slipped to the point of almost-complete failure, with water recycled from the system a very low quality. Recognising this, Scenic Rim Regional Council called tenders for the upgrade of the system, and Alliance Water Solutions was successful in their bid to provide a solution.

“We needed to consider a design that would meet the high demands in terms of wastewater flow and strength from the site, yet one with little impact on the surrounding area,” said Ross Atkinson, Alliance Water Solutions.

Key considerations for the Gallery Walk project were as follows: a system with very low impact in terms of odour and noise, given the proximity to tourist attractions; a system with the ability to cater for large fluctuations in loading; and a system of proven technologies to provide a consistent, reliable source of Class A+ water.

Rather than replacing the media in the existing sand filter, the solution proposed was an entirely new system using, where possible, existing infrastructure but with new treatment elements. A three-stage solution was installed by Alliance Water Solutions:

• Passive primary treatment using the existing treatment tanks
• Secondary treatment through Orenco’s AdvanTex textile filters
• Quadruple-barrier disinfection with membranes, ozone, chlorination and UV for full public health protection.

Taking the innovation one step further, Alliance also developed a captive dispersal system for the excess water not recycled to the toilets; as such, Gallery Walk is one of the few no-release treatment systems in operation in Queensland.

“The system has to be robust enough to cope with low to no flows in the winter through to peaks of 8000 L a day for up to six weeks in summer,” said Daryl Crank, Scenic Rim RC.