A bit of advice from a potty-obsessed showgoer
If you want to find a portable bathroom sooooooooooooooo clean you would hardly know what you can use it to do, follow the pumper.
If you get up early, you can be lucky enough to see, and smell, the clean-up crew with the pumping trucks arriving.
Chase after them, but not as closely as you would an ice cream truck
Because once their work is done, you can do your business.
Be sure to let the fumes settle as you queue up for your turn. Your experience will most likely be much better than having to contend when the facilities near overflow.
This was the case at Overland Expo West in Flagstaff in spring 2025. The cleaning crew surely deserves five stars for their efforts.
Hopefully, all the pit and portable toilets you encounter will meet the same level of cleanliness wherever you go.