Ever wondered what happens to plastic when it's thrown into our waterways?

Here at POA, showing people how plastic waste can permeate through rivers, wetlands, harbours and oceans is one of the most important components of our educational programs. Thankfully, we’ve found a fantastic study which demonstrates exactly how plastic waste can travel through waterways and become so problematic and tricky to clean up.


In March, 2017, the New South Wales Environmental Protection Authority (EPA) threw 40 plastic bottles into harbours, rivers and waterways across the state. What a horrible thing to do! However, these weren’t just regular plastic bottles. The EPA loaded their plastic bottles up with GPS tracking devices in an effort to demonstrate the way in which plastic waste travels through our waterways. The CSIRO had previously found that around 75% of marine debris in Sydney Harbour and its surrounding beaches and in rivers is plastic from local sources. That’s a massive number. In response, the EPA sought to show people how plastic litter can linger and cause all sorts of trouble in our marine environments through this creative experiment.

The bottles were set loose at several locations around the state, including Sydney Harbour, the Murrumbidgee River and the Central Coast. By the end of the experiment, the little plastic vessels had each been on remarkably different journeys. Of the bottles released on river systems, many became snagged in riverbank mangroves, which support very delicate ecosystems, while others continued up to 55kms downstream. Bottles released in Sydney harbour generally travelled around the harbour before making their way out to sea. One bottle was found 45kms from its release point after just a matter of days. One lucky bottle was picked up by a clean up crew in Manly, before it enjoyed a ride to the tip.

The report names Darling Harbour as the most polluted waterway in Australia, and the results of the experiment shows just how plastic waste can be hard to catch once it enters the environment. It is a reminder of just how careful we have to be with plastic, because once it enters the sea, it takes hundreds of years before it goes away. Avoiding plastic is, of course, our best option, but as it is incredibly difficult to live without plastic, we must be extra careful to make sure we dispose of it properly so it doesn’t end up in our water.

Don’t be a “tosser”!


To read the full EPA report, click here.