A mineral long used to treat heartburn is now playing a vital role in managing sewage odour and improving wastewater infrastructure management across Queensland’s Sunshine Coast.
Unitywater has awarded a contract to environmental technology company Calix to supply magnesium hydroxide liquid (MHL) for use at 55 wastewater pump stations across Moreton Bay, the Sunshine Coast, and Noosa. Commonly used as an antacid, MHL is a safe, sustainable solution that helps neutralise hydrogen sulphide (H₂S), the gas responsible for the notorious “rotten egg” smell.
“MHL prevents the production of hydrogen sulphide (H₂S) gas in the wastewater network, which people commonly refer to as the ‘rotten egg’ gas due to its odour,” said Rhett Duncan, Executive Manager Customer Delivery at Unitywater. “It helps reduce any odour, helps prevent fats and oils from congealing and creating blockages, and prevents corrosion in our pipes.”
The initiative is expected to lower operating costs and extend asset life, with MHL also serving as a temporary solution for customer-reported odour issues. Unitywater and Calix are also collaborating to optimise dosing rates using real-time monitoring via Unitywater’s SCADA system.
“Managing it intelligently helps reduce truck deliveries and vehicle movement which, in turn, lowers Unitywater’s carbon footprint,” Mr Duncan added.
With support from Sunshine Coast Council, Calix has opened a new operational site in Caloundra West. “We’re delighted to be delivering more sustainable and cost-effective solutions for wastewater network management,” said Greg Holmes, General Manager, Magnesia at Calix.
Councillor Terry Landsberg welcomed the company’s investment. “Our economic modelling indicates this project will generate a broader economic impact of AUD 7.14 million and support up to 23 direct and indirect jobs,” he said.
The project represents a model of sustainable infrastructure innovation with regional economic benefits.
