That's an excellent and very practical question for anyone dealing with urban wildlife! From personal experience and talking to city waste management folks, there isn't a single magic number for depth, as it depends heavily on the animal. The main culprits are raccoons, stray dogs, and sometimes foxes or cats.
The key isn't just absolute depth, but making it impossible for an animal to get a foothold or leverage to pull things out. A common guideline is a bin that is at least 3 feet (about 1 meter) deep. This depth, combined with smooth, vertical interior walls, makes it very difficult for a raccoon—a master climber with dexterous paws—to hang on and dig. For larger animals like dogs, the depth prevents them from easily reaching the bottom.
However, depth alone often isn't enough. A determined raccoon can tip over a standard bin. So, the most effective strategy combines depth with other features:
* Secure, locking lids: A lid that clips or locks shut is crucial.
* Smooth interior surfaces: No ridges or handles on the inside for claws to grip.
* Weight or bungee cords: Adding weight on top or securing the lid with a cord provides extra security.
* Storing bins in a garage or shed: This is the most foolproof method.
In summary, aim for a bin that is at minimum 3 feet deep with a locking lid. The goal is to create a container that is too deep to reach into, too smooth to climb inside, and too secure to knock over. It's about creating multiple barriers, not just relying on one measurement.