As I recall, the essence of this plan arose in the Eisenhower administration, though I think Ike’s scheme involved routing the Mediterranean to the Jordan by canal. Needless to say, the problem wasn’t the scope of the project, it was the politics of the region. Don’t see that changing any time soon.
The part about the upper reservoir storage is used very successfully in Gilboa, NY where water is pumped up in off-peak hours and released during max usage, essentially a giant storage battery.
As is Banks Lake Wa for the Grand Coolee Dam.
Some really good fishing there....