As a follow-up to our previous film Racing to Zero, and in the same style of investigation, Once Was Water will focus on solutions to global water issues by turning a lens on Las Vegas, Nevada. Las Vegas is a locale that people everywhere in the world know about. It is also the thirstiest city in the driest state in the U.S., so it has had to be proactive in developing solutions that conserve and redistribute water, their most precious resource. Currently, the city is faced with only 2.6 inches of rain per annum, a seventeen-year drought, a constantly expanding population, and competition for shared resources. As the drought that the water bosses were predicting in 2005 drags on into its 17th year, scientists now recognize it as one of the worst in 1,200 years. As a result, the city has become a unique example of what one desert region has accomplished in its search for solutions. They are now at a fine point in their efforts towards sustainability. They have no choice.