Suppose there is an Earth-like world with magic. Someone (maybe wanting a mining city or an isolated power base), thousands of years ago, wanted to build a city on a certain desert mountain, five hundred miles inland and 2 miles above sea level, (This city is on a slope facing in the direction of the ocean. The mountain has sand or dirt--enough, at least, so that the surface is not too hard/rocky to be a barrier to plants growing.) So they had a wizard create a river - that is, a river that flows up vertically, (without the salt and other chemicals), then goes in a right angle, flowing through the air in a straight like till it runs into the mountain. At that point it flows downhill like a normal river.

What effects will the river have on the environment?

  • 2
    $\begingroup$ "sand miles above sea level." that's 4 times the altitude of the Internatinal Space Station. What "slope"? $\endgroup$
    – JDługosz
    Oct 14, 2015 at 7:31
  • $\begingroup$ Well, we can't breathe naturally 10 miles above sea level. That's double Mt Everest. Is your story on an Earth-like planet? $\endgroup$
    – Mikey
    Oct 14, 2015 at 10:09
  • $\begingroup$ "without the salt and other chemicals" then you have distilled water, which is long-term fatal to drink, as it will drain the body of needed soluble chemicals $\endgroup$ Oct 14, 2015 at 16:25
  • $\begingroup$ @SerbanTanasa That's a big stretch. Distilled water is fine, so long as you have another source of minerals needed. $\endgroup$
    – Tim B
    Oct 15, 2015 at 13:16

2 Answers 2


Erosion maybe should be extremely high where the river meets the mountain. Wizard should at least grow many plants before so there is no risk of flood.

In the Cascada del angel (Angel waterfall) in Venezuela sometimes the water doesn't fall to earth because the sun evaporates it before it hit the ground and the Cascada has less than a mile of height.

With evaporation there is going to be a lot of clouds and the river is going to generate a cold front so it's going to be a lot of raining.


(Originally posted when the question was a river at 10 miles high)

The height of the mountain is an issue first. At that height you're in the clouds. Almost out of the troposphere. The river may or may not freeze.

If it isn't frozen it's speed, if great, could cause rather turbulent winds and move the clouds toward the desert. If the river runs OVER the desert than the clouds might rain as they get near the mountain which would cause increased pressure. So you're desert wouldn't stay a desert very long.

If the river doesn't flow over the desert the clouds would rain on the opposite side like they already do which is what caused the desert to exist in the first place.

If the river is frozen or doesn't really flow much, Then you'd not see too many changes to the rest of the environment due to it's height. The river would act like a thermal sink and cool the atmosphere, but that high up the effect would negligible.

The effects of the river at the bottom of the mountain might be a bigger issue. It might create a new lake and finally a river that returns to the ocean eventually. That would affect the area greatly I think.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .