In a 2015 study, the CSIRO found that around 75% of marine debris in Sydney Harbour, on its surrounding beaches and in rivers, is plastic and comes from local sources. Cockle Bay and Darling Harbour were the worst locations in the Sydney maritime area with 2,456 pieces of rubbish per 1,000m² being recorded. That statistic did not include litter below the water’s surface.

This inspired the NSW Government to release 40 GPS tracked plastic bottles into waterways across NSW and tracked their journey for over a month in 2017. This project let the bottles tell the story of:

• Why litter is an important environmental issue
• Why people should put their rubbish in the bin
• How litter travels once it reaches waterways
• How litter can linger in previous mangroves, harbours and rivers.