Wastewater, waste or water?
Posted: 5 April 2017
On the eve of World Water Day, 22 March 2017, the Australian Water Association and WIA celebrated this year’s theme of wastewater by exploring the reuse opportunities and challenges in South Australia.
World Water Day, held annually, focuses attention on the importance of freshwater and advocating for the sustainable management of water resources.
Over time there has been a progression in our industry from disposing of all wastewater as a waste, to using it as a water resource in an environmentally responsible and more sustainable way, to improve liveability and support economic development.
Australia, and South Australia, are leaders in this way. Most wastewater treatment plants in the state have a reuse component for the treated effluent.
One of the major benefits of reusing treated effluent is the reliability of supply. There is the same quantity of wastewater every day; it is not weather dependent like other sources of water. Wastewater treatment technologies and health regulations enable effluent to be treated to a quality that is fit for purpose.
Advances in treatment technology and scientific understanding of risks is seen as an area of opportunity in the future, as we will be able to more closely align and optimise investments in treatment with the intended end use.
Reuse of SA Water’s treated effluent (or recycled water as they call it) in the Northern Adelaide Plains has seen 20 GL/a used for irrigation (instead of being discharged to sea), contributing to jobs and $400 million per year in food production. SA Water is working to double their reuse capacity in this area. Together with investments in managed aquifer storage and high-tech agricultural facilities this opportunity could provide up to 4000 jobs over the next 10 years.
Over the last decade the City of Tea Tree Gully has shifted from using potable water for irrigation to harvesting and treating wastewater from their council-run community wastewater management system (CWMS) and reusing it for irrigation. The drivers for this shift were to reduce council’s reliance on ‘mains’ water for irrigation and to reduce the amount of wastewater discharged as trade waste, both which came at a financial and environmental cost. Council’s wastewater treatment plant opened in 2011, operating at 1.1 ML/d, with the ability to increase capacity to 1.6 ML/d.
The City of Tea Tree Gully are presently supplying 60% of their irrigation requirements from non-potable, fit-for-purpose sources, including their reuse scheme.
Operational efficiency and cost recovery can be a challenge. Although the City of Tea Tree Gully reuse scheme has infrastructure and regulatory approvals in place to enable distribution to residential customers, in the short term council have chosen not to pursue this.
Finding new customers and increasing demand has proven difficult for many wastewater reuse systems. Others face the prospect of major customers closing their operations which requires finding new customers to replace the demand.
Poor public perception of wastewater reuse is still a factor driving the demand (or lack thereof). The general sense is that people are happy to know that wastewater is being reused, so long as it’s ‘not in my backyard’.
Industry regulation, necessitated by rapid growth in the sector, ensures the safety of workers, community, properties and the environment. The Water Industry Act 2012
marked the introduction of more regulation in the SA water sector. There are now five South Australian water regulatory agencies: Office of the Technical Regulator (OTR); Environment Protection Authority; Department of Health and Ageing; Department of Environment, Water and Natural Resources; and Essential Services Commission of South Australia (ESCOSA).
Each of the regulatory agencies has their part to play. Of interest to members is the still new Office of the Technical Regulator. The purpose of the OTR is to assist the functions of the Technical Regulator under the Act:
- Development of technical standards for the water industry.
- Monitoring and regulating technical standards with respects to water and sewerage installation, associated equipment, products, materials and plumbing.
- Provision of advice in relation to safety and technical standards.
South Australian water regulators are regularly collaborating, particularly with regard to their reporting requirements. To find out more visit the SA Government website . Or, if you are visiting the Ozwater ’17 conference check out Case Study – Red Tape Reduction in Regulatory Technical Reporting being presented by Yannick Monrolin of the Office of the Technical Regulator.
Wastewater isn’t going away, it’s something that as an industry we will always have to manage. So even though there may be some short term challenges, there is plenty of opportunity; technological innovation and advances, growth, the potential to link schemes and networks to optimise outcomes and benefits, and increasing regulatory maturity.
Thank you to the presenters and panellists for sharing these case studies, the benefits and challenges of reuse, and their aspirations for the future of reuse as part of the sustainable management of water resources.
Thank you to the audience for their participation in the event and thought provoking questions which drove a great discussion.
The Australian Water Association and WIA would like to acknowledge the event presenters and panellists: Greg Ingleton, SA Water; Gary Beveridge, City of Tea Tree Gully; Anu Atukorala, Mt Barker District Council; Nathan Silby, Wallbridge & Gilbert; and Michelle Wittholz, Department for Health and Ageing.
The Australian Water Association and WIA were pleased to collaborate on this event, which provided a great opportunity for our respective members to meet, network and discuss this important topic.