That's an excellent and practical question. The intuitive answer seems to be "yes," but research in environmental psychology and urban planning reveals a more nuanced picture. Studies suggest that simply adding more trash cans is not a silver bullet and can sometimes have unintended consequences.
The core principle from behavioral studies is that littering is significantly influenced by the existing state of the environment—a concept known as the "Broken Windows Theory." A clean area tends to stay clean, while a littered area invites more litter. Therefore, the presence of trash cans must be paired with consistent maintenance and cleaning. An overflowing can is often worse than no can at all, as it becomes a visual cue that littering is acceptable.
Research, including observational studies in cities like London and San Francisco, indicates that strategic placement is more critical than sheer quantity. Cans need to be highly visible and located at "natural" decision points—near transit stops, fast-food outlets, park entrances, and along common pedestrian desire lines. A study published in the *Journal of Environmental Psychology* found that convenience is the largest factor; people are far more likely to properly dispose of waste if a bin is within 15-20 steps.
However, some analyses point to a potential downside: over-provision can reduce the "carry-in, carry-out" ethic and might normalize the generation of waste on-the-go. Furthermore, the cost-benefit analysis for municipalities is crucial. Installing, emptying, and maintaining thousands of additional bins is expensive, and funds might be more effectively spent on public education campaigns, targeted enforcement in litter hotspots, or designing out the problem (e.g., fewer single-use packaging options).
In conclusion, evidence suggests that a *sufficient* number of *well-placed* and *well-maintained* trash cans does reduce litter in targeted areas. But the most effective strategies are holistic, combining adequate infrastructure with efforts to shape social norms, design cleaner systems, and maintain existing public spaces diligently. The goal is not just to provide a place for trash, but to create an environment where littering feels like a violation of the social and physical order.