On a (colonized) fallen world humans have been pushed to the brink. The planet is a massive desert world with no body of water on the surface, and no rain fall. The only way to get water is from the aquifers underground but even they go dry leaving the settlement to die shortly after.
Society is still advanced in a way, but is more tribal/feudal in nature. Most of the inner towns have 1700 tech level (most don't have access to this and are stuck with medieval tech); war and lack of infrastructure stop them from ever going past this point.
So water being so hard to get, is rationed and protected. Even drinking it greedily can get you killed. the center that hold the most water is straggling to keep up with demand and war has broken out, but drinking water is still available to most people. water is too precious to be wasted bathing, so how would one wash themselves?
Sand baths seem to be the next logical step, but I don't know if it could be a long term solution to the problem. I also don't know how to build one; I was thinking a bath house (sand house) like setup for the whole town to use. Reason for this is I don't think just regular old desert sand would work (a type of sand best suited for washing) but I could be wrong.
The Question: Sand Baths are they Practical for People on Desert Planet?
So any ideas would be great, if you come up with a better idea on how they could wash themselves don't hesitate to answer, just keep in mind the tech level and they can’t build anything fancy. With it being war time trade would be difficult as well.