The mouth of the Columbia River to Southern California. California would take that water and reallocate all their Colorado river allotment upstream. Feds should push this. A pipeline along the coast or even in the ocean would not require much lifting.

Desalination is just expensive. When I visited Israel I asked about desalination. They said they had a couple plants but did not want to use them much because of the cost. It was cheaper to buy water from Turkey and send it south.