Project overview

The Washington State Department of Ecology recently released the results of the 2022 Washington Statewide Litter Study, which measured the types and amounts of litter across different site types in Washington.

Approach and impact

The Washington State Department of Ecology recently released the results of the 2022 Washington Statewide Litter Study, which measured the types and amounts of litter across different site types in Washington.

Cascadia staff collected and sorted litter from 182 randomly selected sites, including roadways, on-off ramps, rest areas, parks, and recreation areas. From these samples, we estimated that 37.8 million pounds of waste are littered each year in Washington—or 4.8 pounds per person. The most commonly littered items by weight are glass beer bottles, construction and demolition debris, and cardboard boxes. By piece, the most commonly littered items are cigarette butts, construction and demolition debris, and food wrappers and snack bags.

The results of this study not only provide a comprehensive picture of litter in Washington, but also provide recommendations for reducing litter and littering behavior such as: adopting a beverage container deposit return law, improving cigarette butt collection, requiring towing companies to remove vehicle debris, developing and implementing behavior-change programs, and reviewing enforcement of covered loads requirements.

Additionally, this study highlighted that while 69-72 percent of littered pieces are covered by Washington’s Litter Tax, only 42 percent of littered pounds are. Currently, the revenue from this tax does not cover what it costs to clean up the amounts of litter we find today.

Ensuring that recommendations for improving littering behavior are grounded in science and supported by data is critical to the success of any future policies, programs, and practices—and we’re proud to have supported such an important effort as the State strives to reduce its litter.

Learn more

Read the full report on the Washington Department of Ecology’s website. 

We collected and sorted litter across the state to understand where Washington's litter is coming from and where it belongs.

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