31 May, 2022

Deal with phosphate issues sustainably, properly

The challenge of phosphate issues and overloaded nutrient levels in fresh waterways is a complex one, but it can be rectified with an innovative Australian invention.

Phoslock® is a proprietary technology originally developed by the CSIRO that removes excess phosphate from waterbodies safely and permanently.

Lachlan McKinnon, Managing Director and CEO of Phoslock Environmental Technologies (PET), says deteriorating water quality is a major global problem.

“Many freshwater bodies around the world have high phosphate loads due to factors such as increased urbanisation, agricultural run-off, high pollution levels and climate change,” he explained.

“Excess nutrient levels result in the eutrophication of fresh waterways, encouraging the development of harmful toxins and problem weeds which can be a serious threat to marine habitats, animals and humans.

“Phoslock is quite amazing – it binds with phosphorus in the water column and lake sediments, settling it in an environmentally benign state.

“Once it is bound, it cannot be re-released into the water again.”

Phoslock is a formulation of bentonite (clay) and lanthanum, a naturally occurring rare-earth element that binds with phosphate to form an insoluble and biologically inert compound.

It has been assessed extensively by independent experts as having distinct advantages over competitive treatments. It is internationally certified for drinking water reservoirs.

“More than 300 Phoslock applications have been made around the world, successfully returning affected waterways to their natural state by removing excess nutrients,” Mr. McKinnon explained.

“The Phoslock granules are mixed with the lake’s water and then applied as a slurry from a barge or the shoreline to the water surface.

“As it descends, it binds with any phosphorus in the water column and then continues to bind with phosphorus present in the sediments.”

In most situations, more than 90 percent of available phosphate is bound within three hours of application with no toxic effects on humans, animals, fish, and aquatic plants.

When London was preparing to host the Olympics a decade ago, Hyde Park’s Serpentine Lake was treated for phosphate issues using Phoslock to achieve water quality sufficient for swimmers.

Recent applications include Lake Hugh Muntz in Queensland, Ladybird Lake in Austin Texas, Heritage Loch in Glasgow Scotland, as well as to the 100-hectare Kralingse Plas in Rotterdam, The Netherlands – the company’s largest treatment in Europe to date.

“Applications like the one at Kralingse Plas in The Netherlands and at Serpentine Lake in London allow for popular recreational facilities to be safely utilised by local communities, at the same time ensuring flora and fauna that rely on the waterway can thrive,” he continued.

“It returns the waterbody to a natural, healthy state in an eco-friendly and sustainable way.”

To find out more, please visit phoslock.com.au/products/phoslock/case-studies/