Hmmm, you may be right. Let me google that…
When I took a raft trip down the Colorado River through the Canyon, the approved procedure was that you would urinate into the river. Unlike many other wilderness waterways, the volume of the water flow was such that the authorities had determined that it was best to have the urine mix into the river and flow off.
For defecation, the rafts carried a series of metal boxes, one for each day of the trip, which were about a foot and half cubes with airtight circular lids in the top, to which a toilet seat could be affixed. They were known as “groovers” because historically, the boxes used for this purpose had been military surplus ammo cans, that received this name because of the lines they would impress upon your lower anatomy when you sat upon them. Modern versions with a standard toilet seat did not cause this issue.
At each night’s campsite, the guides would place the groovers in an appropriate place away from or shielded from the main campsite. You would do your business upon them, place any toilet paper used into them, and sprinkle a deodorizing powder into them after use. Each day before leaving the campsite, the box would be sealed and packed out to be emptied into an upland sanitary system and cleaned after the trip.
One of the pleasant quirks was that the groover locations often had some of the scenic views at the campsites, improving the overall experience of using them immeasurably.