Water: H2O=Life, the exhibition currently featured at the San Diego Natural History Museum, was organized by the American Museum of Natural History and the Science Museum of Minnesota, but it seems particularly apt for viewing here. San Diego County’s nearly 3 million residents consume about half a billion gallons of water a day, but the vast majority of that (80-90%) doesn’t exist naturally here. Some of it comes from Northern California and some from the Colorado River, the latter traveling more than 1000 miles to get to Southern California, where it’s then transported along a 242-mile-long aqueduct before reaching local taps.
A few encouraging new (for San Diego) sources are on the horizon; the nation’s largest drinking-water desalination plant recently was approved for construction in Carlsbad. Work on it is scheduled to start in 2009, with completion scheduled for 2011, and if all goes as planned, it will produce 50 million gallons a day, enough for 112,000 households. But given the historically dry weather we’ve been having, water rationing is still looming.
As the Natural History Museum exhibit makes abundantly clear, however, the problem of having enough fresh water extends well beyond San Diego. Earth may be the water 
planet, but only 3 percent of the stuff that covers the planet’s surface is fresh — the type needed to sustain most life. Furthermore, only a small fraction of that 3 percent is usable.
The exhibit does a masterful and entertaining job of saluting and explaining the many incarnations, impacts, and aspects of water. You can easily spend a good two hours absorbing it all (and that doesn’t include viewing the two complementary films screening in the museum’s giant-screen theater.)
Although the traveling exhibit will move on at the end of November, Water: A California Story will remain on exhibit at the Museum for at least two years. The special exhibition uses natural history specimens, live animals, photos, and interactive exhibits to explore the water issues facing southern California and Baja California.
