How about: turn the water back on to San Juaquin Valley, and grow enough food to feed ALL of No. America? Side benefit: make progressive liberals crazy.
Not that simple. If Salton Sea dries, 100 years of farm run off silt blows through the entire sw United states. It's gnarly shit that causes respiratory problems on the low end and cancer on the high end. Potentially you could dredge it up and clean it but you'd still need to keep it wet to do so. There's also the other complications that now they've found a massive lithium deposit under the region, they're gonna wanna start developing mining there too. So, sadly, diverting water is not a viable option
How has Salton Sea existed all this time?
Long story short: it's artificial. It was an accident during railroad construction back in the early 1900s. By the time they rediverted the water sources, it was already a massive inland body of water. Wikipedia has a good write up on it~~~~