You can understand our optimism. It hadn’t rained in Phoenix for four months. Other parts of the West were hot and dry. Then came the big one: Hurricane Hilary. While rainfall totals were disappointing in Phoenix, the storm did dump quite a few inches on California and Nevada. Areas near Lake Mead got pelted, leading a bunch of folks to presume that the nation’s largest water reservoir would get a decent boost from the rainfall. But that’s not how it works.