If that happens, then sea water will then ebb back up the riverbed, really messing things up!
In Islam, a hadith is mentioned prophecying about unearthing of a gold mountain beneath the Euphrates river before the apocalypse, with many people dying fighting over it; it is said to be one of the future minor signs of the coming of Judgement Day:[66][67]
“Sahih Muslim 2894 c Abu Huraira reported Allah’s Messenger (ﷺ) as saying:
The Last Hour would not come unless the Euphrates would uncover a treasure of gold, so he who finds it should not take anything out of that.”