97% capture of the smallest particles including fine polystyrene from an industrial site.
As New Zealand's largest manufacturer and distributor of polystyrene products, EXPOL is committed to reducing its environmental impact and protecting local waterways.
Recognising the risk of expanded polystyrene (EPS) particles entering the stormwater network during manufacturing operations, EXPOL trialed the EnviroPod™ LittaTrap™ at its Onehunga manufacturing facility.
Installed in May 2016, the trial evaluated the LittaTrap™'s ability to capture small polystyrene particles and other gross pollutants before they entered the stormwater system and receiving environment.
Expanded polystyrene is lightweight and easily transported by wind and stormwater runoff. Once it enters waterways, it can persist in the environment, gradually breaking down into smaller plastic fragments that pose risks to aquatic ecosystems and wildlife.
EXPOL sought a practical, at-source stormwater treatment solution that could:
The monitored catchment comprised approximately 216m² of industrial hardstand surrounding the manufacturing facility.
A 450 × 450 mm EnviroPod™ LittaTrap™ fitted with a Nurdle Liner was installed within the site's stormwater catch basin.
The specialist liner was selected to capture particles greater than 1 mm, significantly increasing the system's ability to intercept small polystyrene fragments while continuing to remove other gross pollutants.
The retrofit installation required no major civil works and provided an easy-to-maintain solution for ongoing environmental protection.
The monitored maintenance event represented 80 days of operation.
During this period, the LittaTrap™ captured:
The trial demonstrated the LittaTrap™'s ability to capture both manufacturing-related pollutants and everyday litter before they entered the downstream stormwater network.
We estimate based on the volume of polystyrene and organic material collected* from inside and around the LittaTrap™, the LittaTrap™ had a gross pollutant removal efficiency of 97% by volume.
* This is based on material collected on the day of the cleaning.
The EXPOL trial demonstrated how simple, at-source stormwater treatment can make a measurable difference in preventing industrial plastic pollution.
Over just 80 days, the LittaTrap™ captured polystyrene particles, litter, and organic debris while achieving an estimated 97% gross pollutant removal efficiency.
The project highlights how manufacturers can integrate practical stormwater treatment into everyday operations, helping protect waterways while supporting corporate sustainability commitments.
Analysis
We estimate based on the volume of polystyrene and organic material collected* from inside and around the LittaTrap™, the LittaTrap™ had a gross pollutant removal efficiency of 97% by volume.
* This is based on material collected on the day of the cleaning.
