I am sure this topic has come up, but not certain where…
I keep hearing rumors of state parks that don’t allow wastewater discharge of any sort from a camp site. While I have not yet experienced this, only rules I Have seen in water discharge has been no black water discharge, and RVs must capture gray water. But tents campers typically get a pass on this, that includes tiny trailer or truck camper shell campers.
HOWEVER, for those that have more stringent campground / forest rules, there are ways to collect gray water for proper disposal.
I personally have opted for a fold up pet pool that fits inside the wet side of my Ensuite tent.
I collect the water in the pet pool, and transfer it to a proper drain close by, or into a water carrier like one of those blue roller gray water tanks to be transported to a dump station.