Ultrasonic sound waves used to combat taste and odour in drinking water

1 Sep 2020

Ultrasonic sound waves are being used as a revolutionary way to manage the impacts of blue green algae blooms that can cause taste and odour issues in drinking water.

Seqwater Catchment Water Quality Advisor Renee Hague said a trial of the new technology at Poona Dam on the Sunshine Coast had delivered promising results.

Ultrasonic sound waves technology is being used at Poona Dam as a revolutionary way to manage the impacts of blue green algae blooms that can cause taste and odour issues in drinking water

Potential taste and odour-producing blue green algae species are present in most South East Queensland dams all year and are most predominant in shallow water bodies.

“Water Treatment Plant processes make sure the drinking water supplied to customers is safe and of high standards, however taste and odour may still be present in drinking water following algae blooms.’’ Ms Hague said.

“Our dams contain complex ecosystems alive with fish and other aquatic species, including different types of algae.

“Many of our dams are seasonally affected by the growth of these algae which thrives in warm, dry conditions and when water in the catchment has high nutrient levels causing a bloom.

“When this occurs, blue green algae blooms can produce and release harmless natural compounds which can create a musty and earthy taste and odour.’’

Ms Hague said there had been several algae blooms over the past few years that had affected the taste in some of the Sunshine Coast’s drinking water.

To combat the issue, Seqwater has engaged algal control specialists to investigate the use of ultrasonic technology as an environmentally-friendly and cheap alternative to controlling blue green algae in the dam.

The technology uses two solar-powered units, capable of emitting ultrasonic sound waves to inhibit the algae from forming intense blooms.

“The ultrasound waves create a sound layer in the top layer of water directly impacts on the buoyancy of the algae,” Ms Hague said.“The algae cells sink to the bottom, where they are unable to photosynthesize and eventually die due to lack of light.

“During the trial period, weekly samples taken from Poona Dam, showed a dramatic decline in taste and odour compounds in the dam.

“As a result, we’ve integrated the permanent use of this technology at Poona Dam, with the potential of rolling out these units at other Seqwater dams prone to blue green algae blooms.

Ms Hague said the continued success of the ultrasonic device could result in significant savings to water treatment costs and improved drinking water quality for customers.