Smaller Holding Tanks...What to do when NO hookups??

Carry extra fresh water in a bladder or tank in the back of the truck. Easy to transfer water with and folds up like a duffle bag when empty.
Look at wake boat fat sacs. Can get a deal for a 400-1000lb bag and pump for around $100. Or maybe used. Lotsa wake boats in Cali.
Bring a garden hose and drain gray out in the woods or weeds after dark. Don’t mind the ninny’s who say that’s bad. Seriously.