You will probably all realize that I am new to this forum and even to the topic in general. I have been working with a boarding school/orphanage in a remote area of Mexico that serves the local natives by providing food, shelter and education to children from age 3-16. Many of the kids have families, but due to the extreme distances they live from the school, boarding at the school is the only option.

Without giving too much detail, as this area is potentially dangerous due to cartel activity, this school has a working "fosa" or basic seepage type septic system and plenty of fresh water. So much fresh water that they have no qualms about leaving taps running for hours and don't fix leaks if they occur.

The main problem that they face is that the natives traditionally clean themselves or "wipe" using a rock. That sounds pretty crazy to me, but you folks have probably heard this before. Someone previously installed 6 flush toilets. Only 4 are still working and none have intact tanks and are flushed by pouring water from a bucket, which is effective enough. The main problem as you may have guessed is that the toilets are constantly clogged with rocks. For many reasons, such as language issues,transience, etc., it continues to be an issue and the bathrooms rapidly become unsanitary...to say the least. The children routinely suffer from conjunctivitis and other diseases that would be reduced by a better system.

I have been trying to conceive of a system that will increase sanitation, be sufficiently robust to withstand use by the kids, not be impaired by the occasional rock and will require minimal maintenance and supervision (both of which are lacking...)

I have considered a trough type system with a combination of a constant low flow and metered flushing system, but I am not convinced it will control odors. Any ideas will be appreciated, and please ask questions if I have left anything out that you need to know. I'm a licensed master plumber, and thoroughly understand modern plumbing, but this is a puzzler.