Dirty secret lurking in water near popular Aussie beach: 'Appalling'

There's a dirty secret hidden in wetlands just 10km away from popular Australian beaches. Researchers have discovered “appalling” levels of microplastics floating in the water, sparking a warning human and wildlife health are at risk.

"The beaches are clean but the wetlands are horrific," an expert at the Australian Microplastic Assessment Project (AUSMAP) told Yahoo News.

It's testing revealed a staggering 796,000 plastic pieces per square metre in the Barker Wetlands, close to Adelaide’s historic seaside town St Kilda and Semaphore Beach. Video supplied to Yahoo News shows hundreds of multi-coloured plastic shards floating on the surface like confetti.

The research was undertaken by conservation program AUSMAP which has linked the problem to runoff from the surrounding industrial area, which includes a plastics recycling facility. AUSMAP's program director Dr Michelle Blewitt said the plastic was long lasting and had been able to accumulate for years.

"The pollution has been going on for years, with little action from environment protection authorities and factory owners… it’s a continual danger to fish and birdlife in the Barker Wetlands and contributes to the microplastic load that is being absorbed by the human population,” she said.

The video below shows just how bad the microplastics problem is.

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Authorities urged to act against 'appalling' plastic problem

AUSMAP is a program of the conservation non-profit Total Environment Centre. Its director Jeff Angel said new approvals by the Environment Protection Authority for industry projects should be accompanied by guarantees that they rein in pollution. “Action to filter out microplastic from urban runoff in the catchment also needs to be taken,” he said.

Blewitt explained many of the microplastics were likely coming from a nearby plastic factory. Others were being blown from urban areas by the wind or water runoff.

“To see so much microplastic in the vegetation and sediment in this vital wetland sanctuary is appalling. It’s gone on for far too long. 130 bird species, including migratory ones from the northern hemisphere have been seen at the Barker Wetlands,” she said.

Authorities say wetlands designed to keep pollution off beaches

Yahoo asked South Australia's Environment Protection Authority why it had allowed the Barker Wetlands to become so highly polluted, and whether it planned to review licences to industry that operate in the area.

It did not respond directly, but issued a statement saying "microplastics are an area of concern for many environment protection authorities across the world" and the wetlands are designed to help manage pollution, and keep it away from beaches.

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"The Barker Inlet Wetlands were constructed in the 1990s to address a range of environmental impacts in the area including receiving and managing storm water runoff, pollution management and flood control from this highly industrial area," it said.

"Stormwater enters the wetlands at several points then is filtered through a series of lagoons before discharging, through a sea wall, into the mangrove estuary of North Arm Creek. Most of the pollutants being washed off the urban catchment are effectively treated and substantially retained in the system, which reduces potential impacts in the marine environment."

It confirmed it is responsible for the control of stormwater pollution and claimed "all reasonable and practicable measures are taken to prevent environmental harm caused by pollution".

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