A total of 1203 pieces of plastic and other pollutants stopped from entering the stormwater system & reaching the Waitamata Harbour.
Supermarkets are among the busiest commercial environments, combining high pedestrian traffic with active loading zones that generate significant amounts of litter and packaging waste.
Recognising the opportunity to reduce stormwater pollution at its source, Foodstuffs North Island partnered with EnviroPod™ in 2016 to trial the LittaTrap™ across several supermarket locations.
The objective was to better understand the type and quantity of pollutants entering the stormwater network and evaluate how effectively LittaTrap™ could prevent litter from reaching the Waitematā Harbour.
The trial demonstrated how simple catch basin filtration can help supermarkets reduce their environmental footprint while supporting cleaner waterways.
Busy supermarket sites generate a variety of pollutants that can be washed into stormwater drains during rainfall events.
Common sources include:
Without treatment, these pollutants flow directly into local waterways where they contribute to plastic pollution and environmental degradation.
Foodstuffs wanted to better understand the scale of the issue and identify practical ways to reduce litter entering the stormwater network.
Working with the Foodstuffs North Island team, EnviroPod™ selected two representative supermarket sites for a monitoring programme.
Five strategically selected catch basins were fitted with EnviroPod™ LittaTrap™ units.
The catch basins represented a range of site conditions, including:
Each LittaTrap™ was monitored over 168 days (approximately six months) to capture quantitative and qualitative data on the pollutants entering the stormwater system.
Each month, EnviroPod™ inspected every LittaTrap™ and:
This consistent monitoring provided valuable insights into litter sources and seasonal trends across the supermarket sites.
Over the monitoring period, the five LittaTrap™ units captured:
This equates to an average of:
Other pollutants included:
Every item captured represented litter that was prevented from entering the stormwater system and ultimately the Waitematā Harbour.
The monitored catch basins represented only a small proportion of the stormwater network across each supermarket.
Using the monitoring data, EnviroPod™ estimated that:
The wider opportunity is even greater.
At the time of the study, Foodstuffs North Island operated 421 retail outlets, including:
If just four LittaTrap™ units were installed at every store, the network could potentially prevent:
LittaTrap™ provided Foodstuffs with a practical solution that could be retrofitted into existing stormwater infrastructure without disruption.
Key benefits included:
The monitoring programme also provided valuable data to help identify litter hotspots and inform future environmental initiatives.
Retail and supermarket sites are important contributors to urban stormwater pollution due to their high visitor numbers and continuous freight activity.
Capturing litter at the catch basin:
Small interventions across multiple sites can collectively deliver significant environmental benefits.
The Foodstuffs North Island trial demonstrated how at-source stormwater treatment can significantly reduce litter leaving busy retail environments.
In just six months, five LittaTrap™ units prevented more than 1,200 pieces of litter from entering the stormwater system, with plastics accounting for three-quarters of all captured material.
The results highlight the potential for supermarket networks to make a measurable contribution to cleaner waterways through simple, scalable stormwater management solutions.
