Fresh water use

I think Rallye2000 has a likely solution. I have not had the basement empty to check out plumbing for a bit. (I usually have to empty about twice a year for some reason about water being in the wrong place and wanting it to thoroughly dry. I’m gettin’ pretty good at packing n unpacking!) I think the only valve that shuts off tank n turns on City is the panel of levers I mentioned before.
I guess I could have much worse problems. It was just one of those things that make you go, “Hmmmmmm”!
Thanks all, david...