That's an excellent and practical question! Getting a precise volume estimate for public trash cans can be tricky because there's no universal standard—it varies greatly by city, location, and purpose. However, I can give you a good breakdown based on common municipal standards.
Typically, you'll encounter a few main sizes on city streets and in parks. The most common pedestrian litter bin you see on corners often holds between 20 to 55 gallons (75 to 208 liters). These are designed for high-traffic foot areas. Larger, heavy-duty bins near transit stops or in commercial zones can range from 65 gallons up to 95 gallons (246 to 360 liters). For major public spaces or events, you might see wheeled containers holding 1 to 3 cubic yards (roughly 200 to 600 gallons).
Several factors influence the chosen size: foot traffic volume, collection frequency (daily vs. weekly), and the goal of reducing overflow and litter. A downtown area will have more, smaller bins emptied frequently, while a park might use fewer, larger containers.
For a specific estimate in your area, I'd recommend checking your local municipal public works website—they often publish specifications for their standard equipment. The key takeaway is that urban planning departments carefully size these bins to balance capacity with maintenance efficiency, aiming to keep our public spaces clean.