Plato's Spring.

Of all the YouTubes or web pages that show Eflatun Pinar, perhaps this one is the closest to what it is actually like today:




The Hittite shrine that surrounds the pool is dated to c.1300 BC, but this place is also known as Plato's Spring (Plato 424/423 BC – 348/347 BC). The legend is that it was here that Plato stopped the flood and caused the waters to run underground.

To see a map, and some photos:
http://www.hittitemonuments.com/

The water is warm and comes up from out of the ground, so the idea of this being the place where the flood ended is hard to understand.

Hittite mythology owed something of its structure and narrative to the myths of Mesopotamia, particularly the latter, Akkadian myths, and the Akkadian myths grew from the stories told by the Sumerians.

If this place is associated with the flood then there are two sets of myth about the control of water: the story of Noah or rather the story of Atrahasis and the gods deciding to kill all mankind.

And the stories of the serpent guardian of the deep, the Kur.

The gods and goddesses carved into the facade at Eflatun Pinar are rising up out of the water. Some of the carvings of the gods and goddesses are perforated, so the water springs out of their bodies. This indicates that the gods have dominion over the water now, because the Kur has been conquered.

A long time before the story of Tiamat and Marduk, the primeval water under the earth contained the great dragon, Kur. In one story it is Enki who goes to fight with the Kur after it steals the goddess, Ereshkigal. The result is that Ereshkigal becomes queen of the Underworld, and Enki becomes 'Lord of the Abyss' and builds his 'Sea palace' at Eridu.

Another story concerns Ninurta, a warrior god, son of Enlil. His weapon, Sharur has 'set its mind against the Kur' and persuades Ninurta to set off to kill the Kur, though it doesn't seem to be particularly troublesome monster.

When the deed is done and the Kur lies dead the primeval waters that the Kur held in check begin to rise. This causes floods and more importantly it means that the flow of water has become disordered, rivers are no longer connected to the deep:

Famine was severe, nothing was produced,
The small rivers were not cleaned, the dirt was not carried off

Ninurta goes back to the body of the Kur and heaps stones over it, building a great wall to hold back the 'mighty waters'. As to the waters that have already flooded the land, Ninurta  gathers them and leads them back into the Tigris, just as Plato was supposed to have done.

Because of this the land is super abundant, the fields produce more grain, the vineyards more grapes, everything is heaped up in the granaries and mourning disappears from the land.

The earth goddess Ki falls in love with Ninurta out of gratitude, and he gives her the 'heap' the Hursag and she is now Ninhursag, queen of the 'magic mountain' that causes the gold and silver, the cattle and sheep, the 'four legged creatures' to multiply and to thrive. Finally he blesses the stones who have helped him, and curses those who helped his enemy, the Kur.

Hititte mythology is hard to find, but Google tells me that Ereshkigal, so loved by the Kur that it stole her away is called by the Hittites, Lelwani a goddess of the underworld "the pourer".

http://www.ling.upenn.edu/~rnoyer/courses/51/BryceHittiteSociety.pdf

And that's about as far as I'm going with this.
I'm not sure how helpful the myths of the Kur are to an understanding of Plato's Spring, just a little more helpful than trying to associate Plato with it, I guess!