Naturally the only place I can add a new bath is the back of the house where we
want to add a 15x40 addition.

The house is on a concrete slab and has a gravity feed to the city sewer system.

Hooking into the current plumbing would mean a LOT of concrete busted up and in
places I don't want/can't bust up.

I've seen sewage ejectors that lift the waste to a higher elevation and allow a
gravity feed to work. Is there anything for the an entire bathroom? toilet,
shower, vanity bowl?

From the back of the home to the front of the home is about 60 feet so I wonder
if an outside lateral addition would work????? maybe I can raise the throne up 6
feet? LOLOLOLOLOLOL

I know it would vary by county & city, but do you think a zoning board would
allow a sceptic system in the rear of a house already serviced by public sewer?