<i>&gt; They came up with a viable plan to make this happen.</i><p>That is a curiously positive take on it. The wikipedia page you cite notes numerous extraordinary consequences to this plan that call into question its viability, to put it mildly. They include widespread destruction to wilderness areas, the relocation of &gt;100K people, and six nuclear power plants worth of electricity to pump water over the Rockies. It has not been seriously considered since the 1970s awakening to environmental destruction of large scale dam building.