That's a great question! Keeping those city bins clean is important for hygiene and odor control, but you're right to be cautious—too much pressure can damage them. Here’s a natural, methodical approach I've found works best.
First, gear up with safety glasses and gloves. Move the bin to a well-drained area, like your driveway. Remove any loose debris and give it a good pre-rinse with a garden hose to loosen surface grime. This step is crucial; it means you won't need the pressure washer on its highest setting later.
For the wash, use a low-pressure nozzle (often a 40-degree white tip or a dedicated soap nozzle) on your pressure washer. Never use a zero-degree red tip—it's like a laser and will dent or gouge plastic or metal. Fill the detergent tank with a biodegradable, degreasing cleaner diluted as directed. Apply the soap from the top down, letting it dwell for 5-10 minutes to break down grease and sticky residues.
Now for the main wash. Switch to a 25-degree (green) or the 40-degree nozzle. Keep the wand at least 12-18 inches away from the bin's surface and use sweeping, consistent motions. Pay extra attention to the interior bottom and lid, which harbor the worst grime. The goal is to let the water's force do the work, not to get physically close.
Finish with a thorough rinse from top to bottom, ensuring all cleaner is removed. Leave the bin upside down or with the lid open in the sun to air dry completely before putting a new bag in. This prevents mildew. The whole process is surprisingly satisfying and leaves your bin looking and smelling fresh without a scratch.