It's America...we could do it.
Well, a cross-continental water pipeline, of course.
We have such direly varied weather circumstances across our continent--Texas in the middle of it's worst drought ever, and yet again this year, hundreds of thousands of acres of land (much of it inhabited) engulfed in wildfires...yet across the nation, so much rainfall in so many states that hundreds of homes are caught on film and video literally sliding off newly-created sinkholes into rushing waters (where previously only dry land, or even city streets had been before).
Public outcry against high gasoline prices is well-deserved--it's almost as though the layout and geographic location of our fuel pipelines are merely one of many pawns being played by oil companies in a global chess-game to outsmart us, confute us, and defraud us.
A continental water pipeline would be more useful than a gas pipeline, and could pay for itself in a short time by saving us hundreds of billions; we could utilize it to move mass quantities of water from one state to another to ease flooding, and also provide it to areas engaged in massive firefighting situations.
If one region had been hit by enough constant rainfall to cause historic flooding, while another was in the middle of its worst wild-fire in decades, water could be transited from the flooded region to the one in flames, and used to fight the fire.
Another less dramatic--yet arguably just as important--purpose of such a system would be to provide one area in drought with priceless irrigation directly from another with an excessive supply.
Strategic planning could pinpoint areas with historically self-leveling water tables, and locate aquifers in the other areas, to drain or store water by moving it the hundreds of miles necessary to balance the differences that are creating such dystrophic, calamitous, and disastrous conditions everywhere in the United States.