How Leduc uses AI to keep plastic out of organics carts

· The Pulse

A Leduc pilot program that uses artificial intelligence to help residents keep plastic out of organics bins has been extended to the end of 2024 after the city saw a significant reduction in contamination.

Back in June 2023, when Leduc introduced the Organics AI program, roughly 20% of the organics carts its crews collected were contaminated, usually with plastics. This created a problem as processing facilities won't accept organics over a contamination threshold.

Leduc wanted residents to sort their waste properly and brought in AI to help shift behaviours.

"When the collection truck goes to a household and picks up the cart, a photo is taken of all the items that fall out, and the AI tech can identify whatever contaminations we set," said Michael Hancharyk, environmental manager with Leduc.

If the AI notices a contaminant (Leduc is mainly targeting plastic film for its program), a human looks and confirms the AI is right. There is a GPS chip in each bin that matches it with the house's address. Then, the city sends an educational mailer to the house with a photo of their contaminant.

Hancharyk said the mailer has tips for what should and shouldn't go into the cart. "Then hopefully, the resident thereafter learns from their mistake and can compost better," he said. The city also recommends residents download an app to learn more about waste sorting.

A recent waste audit found that since the program has been active the contamination rate for organics carts dropped to less than 10%. Hancharyk said the city sent out 900 mailers in the first eight months of the program and that each month it sends out fewer of them — though that may be a seasonal trend, as there are no lawn clippings in the last few months of the year and therefore fewer compost bins have been put out for collection.

There have been some bumps along the way, too. "We've seen 13 houses that are continually receiving mailers," Hancharyk said. "We're now moving to a formal letter to these 13 households, but 13 households out of 10,000 houses is really low, less than 1%."

A photo of black and green compost bins.

The City of Leduc uses AI to scan what people put in their compost bins, looking for contaminants. (Supplied/City of Leduc)

Regina-based Prairie Robotics is running the tech side of the project. Prairie Robotics CEO Sam Dietrich said the company originally created AI technology to help with more accurate reporting at landfills in Saskatchewan.

But Dietrich said cities had more interest in installing the cameras on the waste trucks themselves. "If you look at other utilities today, whether that's water, electricity, or home heating, every single month you're getting feedback on how much you're using, and you can use that information to change your behaviour," Dietrich said. "But waste is the only one where no city really is actively messaging their residents on this issue … Our goal is to be that piece of feedback."

More than 20 cities in North America now use the company's technology. "The AI ideas we use are no different than how computer vision works for self-driving cars: you train an AI to look for certain objects, and as you build up a dataset of those objects, you're able to identify it in new images that you haven't seen before," Dietrich said.

The tech can blur out sensitive information, like letters on a piece of mail or a prescription bottle.

A picture of a card that Leduc mails to people showing contaminants in their compost cart such as plastics

The City of Leduc sends out a postcard like this when contaminants are found in a household's organics carts (Supplied/Prairie Robotics)

Leduc has extended the pilot project to the end of 2024, and Hancharyk said he believes it will become permanent if the success continues. "We're seeing a lot of attention from the region, so other communities might adopt it based on the success in Leduc," Hancharyk said.

Prairie Robotics will be partnering with more Alberta cities starting this summer, Dietrich said.