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Julie Cook Kitchener Mar 9, 2026 12:34 pm
Hi all, 

The Region of Waterloo in Ontario, Canada, has just begun collecting organics and waste carts with trucks that have mechanical arms. To encourage proper waste handling and cart placement, the Region has developed a series of prompts that provide residents with feedback on their performance. If the carts are placed properly, a household will receive a gold star sticker that says “Great job! You’ve set out your carts correctly. Small actions make a big difference!” This is followed by a QR code that presumably leads to the Region’s website.

In cases where the resident has made an error, an Oops! sticker will be placed on the cart. These stickers act as an educational tool to inform residents when there is an issue with their waste. The following are the different types of stickers and what they mean:

Pink = Not allowed

Orange = Not bundled properly

Turquoise = Too heavy

Purple = Too many

Blue = Contents were frozen

Yellow = Wrong day

White = Incorrect cart set out

Green = Incorrect extra garbage bag set out

As a refresher, prompts are visual and auditory aids that help us remember to do activities we might otherwise forget. Further, the purpose of a prompt is to encourage us to carry out a behavior that we are already predisposed to do. In the case of waste sorting and setting carts out correctly, we can be sure that most people want to do this well. They just need reminders like the Oops! stickers mentioned above to guide them in the right direction. These prompts are effective because they are specific and occur close in space and time to the target behavior. 

For more details on the above Oops! stickers, click here. To learn more about prompts, consider ordering the 4th edition of Dr. Doug McKenzie-Mohr and Jennifer Tabanico’s book here