A man examines Santa Monica library's environmental display of 144 gallons water representing what an average Santa Monican uses each day on Saturday, September 29, 2007 at the Main branch. Santa Monica is joining its sister water agencies across the southland to promote simple ways that each of us can contribute to statewide water conservation efforts in what is now California’s driest year on record. If everyone saved 20 gallons of water a day, the Southern California region would be protected against severe water shortages this summer. The “20 Gallon Challenge” asks every person to save this much water each day—at home and at work—by implementing simple strategies for both indoor and outdoor water use.