Water Conservation in California: Insurance Against Droughts and Blackouts Mary Ann Dickinson Executive Director California Urban Water Conservation Council Sacramento, California  Robert C. Wilkinson, PhD Bren School of Environmental Science and Management, and Department of Environmental Studies University of California, Santa Barbara Abstract Water conservation has only within the past twenty years become a policy reality in the United States, principally because of the general perception that there were seemingly endless supplies of available freshwater and therefore no need for definitive governmental action. But since 1950, the nation’s total water supply withdrawals have nearly tripled , primarily due to rapid urban population growth and an improved standard of living for U.S. residents. At the same time that this increase in national water withdrawals has occurred, protective environmental laws and regulations were enacted to avoid further ecosystem impacts to sensitive watersheds. For the first time, the demand for water in the United States was beginning to outstrip the supply.  In the 1970’s, water conservation and water efficiency began to emerge as a viable and affordable solution, one which could lessen the growing gap between available water supply and consumer demand, and one which also could save money by deferring into the future the need for constructing expensive new water supply facilities. Even where water supplies have been abundant, often the high costs of treating wastewater make water conservation financially attractive. By way of illustration, the nation is expected to pay over a quarter trillion US dollars by the year 2020 to build needed new drinking water treatment and wastewater treatment facilities. Thus, every gallon conserved at the outset by the consumer reduces the need for construction of new additional water and wastewater treatment facilities.  In summary, water conservation is being implemented not only for drought shortage management purposes, but also as part of a long-term public strategy for providing reliable drinking water supplies and affordable wastewater treatment.