Experiment No. 1 involved seeing if a Sim would actually swim from one level to another, in a standard pool, built in steps using CFE.

Three pools, with a bit of horizontal separation, on three descending levels.

Turned off CFE, and built more pool tiles between them, to connect the three.

The result is kind of cool, and yes, my test sim did swim from the first pool down to the third, no problem.
Experiment No. 2 was placing animated water overlays on the three pools, which did make the water look like it was flowing, but only when viewed from above... getting the appearance of an actual waterfall is going to be tricky. I have some sort of translucent curtains that I use to hide modern things; if they came in a convincing waterfallish recolor, it might help.

BUT... the Sim does appear to be leaping off a rock into the pool, thanks to an invisible diving board recolor and a deco pond rock. Since the pond rocks were found in the gardening section, maybe they're not actually coded as sculptures, which might conceivably block a Sim from using the diving board. Anyway... more work to be done. I just moved this new Sim onto the bare lot, it'll save time because I don't exactly know what I'm doing, and will probably have to go through several strategies before I find one that works. I was actually coming up with interesting ideas as I fell asleep last night... it's just a matter of remembering what I was thinking.

Did you see these waterfalls? Could help with the effect of running water

https://modthesims.info/d/237912/th...all-update.html
https://modthesims.info/d/647734/in...waterfalls.html
https://modthesims.info/d/275659/wa...of-rocks-d.html (shower)
(I've seen various edits and recolors of these, too).

The waterfall shower is too tall for this particular use, but I will definitely put it to use elsewhere... possibly on this same lot, who knows? I have the medium-sized one with the sound fx, that went with the "hippo" fountain. I forgot to take a second screenshot after I added a couple of them, and they do add to the overall effect. The one I really want is the shorter one, that has an invisible recolor of the rock parts, so the falling water could be placed by itself. It seems like I might need the Glamour Life SP, though, which I don't have... I can try installing it, I suppose, and see if it even shows up...


The pond rocks, when placed over the "waterfall pool" construction, did a pretty good job of masking out a lot of the ugly blue chlorine water. The only thing was: although the Sims could swim through the rocks, they couldn't exit the pool when there were rocks anywhere near the ladder, and I had to fiddle around in order to position them right... seems like 2 spaces away was the correct buffer. However, in reality, I don't need a swimmable waterfall sequence, just a pool at the end of the cascade. SO... I'm going to download the invisible falls and see what happens.


The small waterfall does not appear in my catalog, or at least, I couldn't locate it. However, you can see the addition of the middle-sized base game falls are pretty nice. When I rebuild the lot in its permanent location, I can do a better job of terraforming ahead of time so I won't have to pile up the pool rocks quite so crazily. The animated "river" overlays do a great job of hiding the swimming pool water, and if I make the pools a little longer, the overlays will fit better.


Now, perhaps some more reddish gravel to place around the streambanks, to match that at the actual site...

An update... the basic building is done; just a matter of tweaking a few things.

As before, I made a series of swimming pools at descending elevations. Macarossi's "base game waterfall" is a bit taller than I would like, with a pointy rock part at the top, so I had to make sure that each pool was sufficiently lower than the preceding one, to accomodate the height of that fall.


Turned off CFE and connected the pools, going from top to bottom (the direction doesn't matter in terms of function, but it will make a difference in the size of the pools involved - if you go uphill, the lower pool will extend back into the hillside, and downhill, the opposite). Also interesting - the first time I did this, I mistakenly typed "off" instead of "false" in the cheat code, and it accomplished the exact same thing, which I thought was kind of weird.


With moveobjects on (or maybe "true" ), I placed all kinds of deco stuff, starting with the JB Animated Water overlays. These are 3x3, which I had to take into account when building the pools. Even so, I goofed and, rather than step backwards, I just overlapped them. It's not as noticeable as with the static colored overlays, where you definitely see the overlaps. For anyone using these, the direction of the green arrow is the opposite of the water flow animation. Also of note: while Sims will happily swim through these overlays, they cannot fish through them. I recommend using Sun & Moon's Gone Fishin' mod from Plumb Bob Keep, which contains a "fish anywhere" spotter; your Sims could theoretically fish from their toilets with it (although I haven't actually tried that, so don't take my word). Even with the spot, the Sims still need a level piece of ground to stand on while they're fishing. A bunch of the Sun & Moon content requires OFB, but some parts work without it. Unfortunately, the worm baits - which are buyable even without OFB - cannot be placed on comm lots, so I'll have to have my Sims bring them with in their inventories if they want to go fishing at the Waterfall Place.


After the water overlays and the fishing spot, I started layering up the deco pond rocks. Because these are slaved, (if that's the correct term), it was a bit of a trial and error to get the correct ones to appear where I wanted. Even with moveobjects on, they sometimes wouldn't place exactly where I needed them (a crowding issue, maybe), hence the few remaining gaps of bright blue chlorine water visible at the falls... that's the next problem to solve. Even after I re-painted the pool walls and floors, the tint of the water is still obnoxious to me. Fortunately, it's only at the point where the pools flow into each other; I think it's just a matter of finding the right deco thing to mask it off. Oh yeah, make sure CFE is turned back ON, before recoloring the pool floors.
At this point I also placed the invisible diving board and pool ladders.


Finally, to further the illusion, I placed the animated water overlays across the roadway as well, because having a river appear from out of nowhere would be weird. I had a moment of panic when my test Sim arrived at the lot on horseback, and instead of pulling all the way up to the "public phone" (disguised as a road sign), parked it just shy of the animation overlays. I thought this might indicate a fatal flaw, but he did in fact dismount from the horse, and went swimming, and was able to leave the lot again afterwards. The horse still wouldn't cross the stream, but I can live with that.


So there you have it. It doesn't look like I'm going to be able to use the small waterfall from Macarossi's Pond in July set, which would probably be ideal for this project. It's in my DL folder, but I don't have Glamour Life. Unless someone can figure out how to make that work without the pack, I'll just have to find something else that could be placed in between the pool levels, to give the illusion of a short waterfall.