This interactive tool presents the results of a study that evaluated the performance of the San Bernardino Valley Municipal Water District water plans-specifically, the 2015 Regional Urban Water Management Plan-under a range of future conditions. Researchers assessed whether demand for water outstripped the sustainable use of supply sources in the Valley District service area, taking into consideration future uncertainty in climate, drought, imported water supply, and water demand. The research team evaluated water supply and demand across 1,872 plausible futures; defined key future vulnerabilities for the Valley District; determined whether new local water supply projects and demand-management options reduced future gaps between supply and demand or whether additional measures are needed; quantified future uncertainty; and identified signposts that indicated when demands might exceed supplies and when management plans might need to be adapted.