Reducing algal blooms with mining by-products

January 31, 2011
Blue-green algae (or cyanobacteria) on the Swan River, Perth, WA. 2000. Credit: CSIRO

CSIRO research has shown that some mining by-products can be effective in preventing nutrients from entering river systems, thereby reducing the potential for algal blooms.

A joint project between CSIRO and the Western Australian Department of investigated a range of by-product materials, which are currently unused, to determine whether they could instead be used to filter nutrients from natural waters or to treat wastewater that would otherwise be discarded.

CSIRO project leader, Dr. Grant Douglas, says the use of abundant, low-cost by-product materials generated from mineral processing offers a potentially cost-effective and environmentally-friendly strategy for the removal of nutrients.

“The largely unexploited by-product materials we generate in Western Australia could be developed as ‘designer’ contaminant adsorbents,” Dr. Douglas said.

After assessing a range of potentially suitable by-products to determine their efficacy in removing nutrients or reducing acidity, a four-year field trial was conducted with a potentially suitable by-product.

The by-product was added to soil at a turf farm in the Swan Canning catchment, and was shown to remove 97 per cent of phosphorus and 82 per cent of nitrogen from the shallow groundwaters. Adding the by-product also reduced water use and improved turf health.

With around 400 hectares of turf farms currently under cultivation over the Swan Coastal Plain, use of this by-product as a soil amendment on turf farms would equate to the removal of around two tonnes of phosphorus and nitrogen from groundwater each year.

“This is good news for the health of Perth’s waterways, as it could lead to a substantial reduction in the key nutrients that eventually contribute to ,” Dr. Douglas said.

“The productive use of the by-products also has the potential to reduce the environmental footprint of mining and mineral processing industries by lowering by-product stockpiles.”

The potential benefits of this project could be realised anywhere in the world where similar by-product materials are produced and similar water management issues exist.

The research is being delivered through CSIRO’s Water for a Healthy Country National Research Flagship for the Water Foundation of Western Australia, which promotes water-related research and development activities within Western Australia.

Explore further: CSIRO 'hot rods' old telescope

Related Stories

CSIRO 'hot rods' old telescope

October 13, 2010

CSIRO has helped transform the University of Sydney's radio telescope into a world-class instrument, and along the way has learned lessons for its own ASKAP (Australian SKA Pathfinder) telescope.

Groundwater threat to rivers worse than suspected

November 2, 2010

Excessive groundwater development represents a greater threat to nearby rivers and streams during dry periods (low flows) than previously thought, according to research released today by CSIRO.

Willow removal equals water savings

December 1, 2010

Removing willows growing in the stream bed of creeks and rivers could return valuable water resources to river systems, new CSIRO research has found.

'Healthier' grains product of research collaboration

December 17, 2010

Four of Australia’s leading research institutions will collaborate closely over the next three years to fast-track development of new, ‘healthier’, strains of three of the world’s most widely cultivated ...

Robotic glider to map Moreton Bay impacts

January 20, 2011

A $200,000 CSIRO coastal glider is bound for Queensland to be deployed in Moreton Bay to investigate the impact of the recent flooding on marine ecosystems.

Recommended for you

Can Paris pledges avert severe climate change?

November 26, 2015

More than 190 countries are meeting in Paris next week to create a durable framework for addressing climate change and to implement a process to reduce greenhouse gases over time. A key part of this agreement would be the ...

Don't forget plankton in climate change models, says study

November 26, 2015

A new study from the University of Exeter, published in the journal Ecology Letters, found that phytoplankton - microscopic water-borne plants - can rapidly evolve tolerance to elevated water temperatures. Globally, phytoplankton ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.