Specific shift/flag problem

There are three switches in an area (let us assume for simplicity's sake that there are three interconnected rooms each with a switch). The area is accessible via a shift. The switches work in the following way: There's a shift on the same tile as the switch, the shift teleports you to a room which is identical except for the tile of the switch, which has changed from off to on (and vice versa).

Each switch has effects which change the other two rooms. The effect is raising the level of the water (oh Lunar, how original, did you think of it all by yourself?) in the whole of the area. The switches work cumulatively. If any two switches are on, the water is at level 2, etc. Is there a way to do the following:

a) Somehow use warps (or anything else really) so that I don't have to copy/paste the whole area for each differrent combination of switches, even if they have the same overall effect on the water level?
b) Make the level remember the level of the water, so when you leave the area and come back via the shift on the door, not only the water is on the level you left it, but the combination of the switches is remembered?

A quasi-abstract answer would be very much appreciated. I can provide more details about the exact locations of things, effects and shifts although the general idea is right there.

Bear with me.
Would this work:
Have two copies of each switch room, and when you exit or enter any of them, a different warp is selected. Exiting the room is based on flags possibly activated by other switches therefore calculating the height of the water in the area. Entering the room is based on a specific on/off flag for the specific switch, the room of which you are entering.

Could this be done? Am I getting on the right track? A check of multiple flags which determine the outcome of the warp, is it possible?

Maybe.. I think the flags would make this way more complicated than it needs to be.

About leaving/re-entering: That, you could do with flags, one for each switch.

So is there a simpler way PP?

Not really. I'd just duplicate the (3) screens. Unless there's a huge span in between them. Is that the problem?

Yeah the three screens by definition need to be duplicated, but I'm trying to avoid duplicating the whole area around them 6 times. (There are a couple more combinations than you would expect.

There are 8 switch possibilities. 2³

You could have the switches set flags 0-2 on or off. And then, when you enter an are use a series of flag warps on both sides of the room thus: