Water purification

bawtp_mf_1WaterSecure supplies South East Queensland with safe, pure, climate-resilient sources of water. One of these new sources is purified water.

Our purified water scheme consists of three world-class advanced water treatment plants—located at Bundamba, Gibson Island and Luggage Point—and more than 200 kilometres of pipeline connecting our source water, our plants and end users.

Our advanced water treatment plants take water that would otherwise be discharged into the Brisbane River and purify it to exceed drinking water standards by passing it  through seven barriers including microfiltration, reverse osmosis and advanced oxidation by UV radiation.

Through this process we are also helping to improve the health of the Brisbane River and Moreton Bay by reducing the amount of nutrients and pollutants that would otherwise be discharged into our waterways.

Purified water is safe to be added to our water supply and when dam levels drop below 40 per cent will be used to supplement Wivenhoe Dam. Find our more about water quality control and results.

The water purification process

Advanced_water_treatment_processTransfer raw water from wastewater treatment plants at Gibson Island, Luggage Point, Oxley, Wacol, Goodna and Bundamba via a network of pipelines. The treatment plants remove a significant amount of impurities and micro pollutants.

Pre-treating involves coagulation, flocculation and the removal of bacteria and phosphorous.

Pretreatment

Microfiltration involves passing wastewater through very fine hollow fibre membranes 0.1 to 0.4 micrometres in size (human hair ranges in size from 20 to 200 micrometres in diameter) that remove particulate matter, protozoa and some viruses. After passing through the membrane, the filtered water mostly contains dissolved salt and organic molecules.

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Reverse osmosis involves forcing filtered water through a special membrane at high pressure to remove impurities such as dissolved salts, viruses, pesticides and most organic compounds. The membrane acts like an artificial kidney. RO produces water of a higher level of purity than drinking water. It is the same process used to desalinate seawater.

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Advanced oxidation exposes the water to ultraviolet light combined with hydrogen peroxide to sterilise and eliminate remaining organic compound traces. The UV intensity is around 300 times that of the sun’s rays. View an interactive animation of how the advanced oxidation process works.

Stabilisation prevents corrosion of piping and pumping equipment, involving the addition of lime and carbon dioxide to return the water to its original levels of hardness and alkalinity. Disinfection involves adding chlorine to prevent biological growth in water pipes and storage tanks.

Purified water is ready for use by industry, agriculture and adding to drinking water supply, if needed. Blending purified water with reservoir water is called indirect potable use.

The nutrient concentrate generated during the advanced water treatment process is treated to remove phosphorus and nitrogen before being discharged into the Brisbane River and Moreton Bay. As a further benefit to us and our environment, the discharge releases much lower nutrient levels into the environment than current discharges from existing wastewater treatment plants.

Take a virtual tour of the Bundamba Advanced Water Treatment Plant and take a look inside the water purification process. The virtual tour includes videos, maps, 3D animations and interviews.

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