Litter studies

Litter studies provide information about the types, amounts, distribution, and sources of litter in the state. They can also provide valuable insights on residents' attitudes and behaviors around littering. This information helps inform and evaluate litter prevention efforts over time.


2022 Litter Composition and Generation Study

With restored funding, we conducted a comprehensive litter study throughout 2022. This study establishes current information about the distribution, types, amount, and sources of litter on Washington roadways, interchanges, and public areas. Having current data on the types and amounts of litter helps us develop strategies to prevent litter and littering behavior, and measure progress over time. 

Read the 2022 Litter Study Fact Sheet. The complete litter study report will be available by June 2023.

2022 Litter Study highlights and infographics

Check out this Story Map to see where we measured litter, how many pounds of litter are on roadways and public areas each year, the most littered items, and the amount of litter covered by Washington's litter tax.