General Waterfall question

[orionunas]

So I've tried doing some research but have not found anything that I could understand or was looking for. Perhaps the community can help!

I understand the basic principles of the waterfall. Logically, there are two ways a waterfall (I also understand there is some contention around what a waterfall is...) can exist.

1) it's from a basin on a high surface and falls off an elevated surface to water level ground.
2) it's from water level to a land mass under water level.

Now my question is about the 2nd form.

If land is below water level, where does the water run? I'd assume it would go to some underground cave system, or if it goes no where it would fill until it became ground level water?

I ask for the purpose of a D&D map I'm making. Trying to think logically about a fantasy world! heh.

Thanks for any help the community can throw my way!

[XCali]

I had to think about something like this for my free Nessa'Mor map. It is definitely an interesting talking point.

For number two, it is not too far fetched, the water would flow into the rock somewhere and in the end with thermal heating end up going back topside. Think about geysers, that is deep underground water boiling to a point where pressure sends it rocketing to the topside. Though, there are quite a few different types of geysers.

The important part is that there is solid rock somewhere if the water being on water level is close by.

Hope that helps some.

[Falconius]

I'm not really sure I understand what you mean by water level? The ultimate water level is of course the sea, but honestly it doesn't matter, only the locality matters, and the principle is simple; water goes down and fills basins till it's level with the lowest point of the rim and then escapes downhill again.

[Redrobes]

I have a thread on rivers and waterflow here:
https://www.cartographersguild.com/s...ead.php?t=3822

But I agree with Falconius, I dont believe there is such a thing as an absolute water level. Even within the underground confines of a hill the water table is variable and forms a curved surface as it permeates across the hill. It flows out of springs or out of a crack or cave opening and the water level behind that in the hill will be about that level but it would rise as you go into a hill further.

Water always flows downhill. It may flow into ground that around it everywhere has a water table higher than that point in which case it must pool and then it will evaporate to form an Endorheic basin.

https://en.wikipedia.org/wiki/Endorheic

Ultimately, water must flow to the sea or get evaporated away. The sea level is of course not a static value either since it varies across the globe due to changable gravity, earth spin and also, more prominently, with the tides.