Blue Boat Home learning to live together sustainably

Three problems with this setup: there's no automatic flapper valve to prevent backflow; the manual shutoff for the toilet (right) is rusted solid, and the floor drain (left) is downstream from the shutoff valve (or rather, upstream if the sewer backs up again).  The new setup runs the floor drain the long way around to the right of the shutoff valve, which is now a plunger/knife type instead of a wheel, and there's an automatic flapper valve right beside the plunger with a cap on it so we can clean it out if it gets clogged.