What I'd like to talk today is two famous seas very much mentioned in the Islamic and Christian scriptures. It is said that there exists two seas that is beside each other, but the contents of the seas do not mix with one another. That's what I knew previously, upon careful research, this is the story. Any mistakes/errors are purely a mis-representation of facts from various documentations/reports I read. I try as much to do a proper cut and paste summary from what I've found.
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What you see in the photo here are two lakes (which is actually in called a 'sea' from ancient times, but categorically it is still a lake) that is actually connected by River Jordan which goes through Syria, Israel and Jordan. I won't go to the beginning of the river, since there are four difference sources giving water into the river and all gather at Lake Hula, near the border of Syria and Israel (but I don't know which country it really resides in).
Now, the Sea of Galilea (also known as Tiberias Lake) is 213 meters below sea level (2nd lowest lake in the world) and water flows 25km downwards from Hula Lake through River Jordan. It is a freshwater lake, a very popular resort area in Israel, have very good flora and fauna and abundance with fishes.
At the south tip of the lake, the River Jordan continues its journey to the Dead Sea (420 meters below sea level, being the lowest lake in the world). Interestingly, there is no outlet from the Dead Sea.
The Dead Sea, in Palestine, Israel and Jordan has no problem with water spillage due to the high evaporation rate against the very low rainfall. In fact, in these few years, the water level is getting lower as compared to earlier years. It is the second saltiest (11 times as salty as the Mediterranean sea) place in the world where only unique creatures thrives. It's high saline content makes anyone lying down in it floats without any problems, and no floras or faunas, or fishes can live it the waters.
A quick summary on the reason why Dead Sea do not get the same 'life' from River Jordan that Sea of Galilea gets is due to the water movement in the Sea of Galilea. It seems that as the water travel south in Galilea, the vegetation started to be of a saline vegetation, and this issue is growing rapidly northwards. Scientist blames this on the channel that diverted water in 1964, which damaged the eco-system.
I won't delve into a thesis on this story. It's just to give an overview of what I was trying to seek an answer to. Practically just to quench my question on the story of "The Two Seas that don't mix" that I've heard in my childhood days.