After conducting a literature review, sign prompts and waster receptacles were employed in a pilot program for highway litter control. There were three conditions in the pilot program. The first group had a sign prompt indicating the presence of a trash can * mile away. The second group had only the waste receptacles on either side of the road. The third group had neither the sign prompts nor the trash can. The amount of littered items present for a six mile stretch of highway was counted to judge the effects of the prompts and trashcans.
Overall, litter was reduced by 28.6% when trash cans were present. No statistical differences were found between the highway with sign prompts and the highway without.