[Tagging] Identifying pit toilets

[Bryce Nesbitt]

For amenity=toilets there are lot of suggested attributes:
http://wiki.openstreetmap.org/wiki/Tag:amenity%3Dtoilets

But among them none would distinguish a pit toilet from a flush toilet.
More importantly perhaps would be does the toilet have water and 
handwashing available.
Some toilets may be "waterfree" (especially on the men's side urinal) 
but still have water
for handwashing.

Would people support a new attribute, and what would you suggest?