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OOaS?9 is much less than the national average. The require- ments for some uses, such as cooling and ore processing, are often met by water of such poor quality that it is unfit for most other uses. Municipal, Industrial, and Domestic Water Status About 3.3 million acre-feet of water for municipal, industrial and domestic uses was consumed in the Pacific Southwest in 1965. This represented about 8 percent of the total water used in the area. The largest centers of population and industry are in arid or semiarid areas where the bulk of the local water supplies was developed and appropriated for irrigation. As the cities expanded onto land formerly irri- gated, their needs were met by acquisition of rights to the irrigation water, by overdraft of groundwater, and by importation from distant sources. Phoenix and Tucson, Arizona; Las Vegas, Nevada; and Bakersfield and Fresno, California, are all in areas of heavy groundwater overdraft. Most of the large cities on the California coast rely heavily on importation. Water from the Owens Valley east of the Sierra Nevada was imported to the Los Angeles Area as early as 1913. Colorado River water was imported to the Los Angeles area by 1941 and to the San Diego area by 1947. The San Francisco Bay area imports water from the western slopes of the Sierra Nevada. Although several desalting plants in both the eastern and western parts of the United States have supplied water on an experimental basis, only two small communities (Buckeye, Arizona, and Coalinga, California) have relied on desalted water to meet their domestic needs. The per capita use of municipal water in the Pacific Southwest generally is above the national average because of the large quantities of water used for lawns and gardens. Lack of metering in some areas and low water rate structures are contributing factors. Projections indicate higher per capita consumption in the future because of rising living standards and expanding use of water-using appliances. However, many factors, such as increasing costs and scarcity, may alter the trend. Except for mining, industry did not become a major influence in the development of the Pacific Southwest until World War II. Then many industrial plants - chiefly in the electronics and aerospace industries which required water for the employees but little or none for industrial processing - were attracted to the area by the favorable climate and labor market. Because of the nature of these plants, the use of industrial water in relation to productivity Needs and Problems When facilities for diversion of Colorado River water into central Arizona are completed, California will have to reduce its use of surplus Colorado River water. Pursuant to a California intrastate agreement it is anticipated that the reduction (more than 1/2 million acre-feet) will be taken from water now delivered to the southern California coastal plain. Southern California water agencies have already made arrangements to replace this water. The annual withdrawals and depletion of water for municipal and industrial needs summarized for the area by time frame are ,hown in figure 6. The requirements for municipal and industrial use are projected to increase at a rate slightly faster than the rate of population growth (pacific Southwest per capita average - 149 gallons per day in 1965 to 192 gallons per day in 2020). Some of the water withdrawn for municipal and industrial use is consumed; some, after adequate treatment, may be discharged to a stream where it can be withdrawn again. The estimates of the consumptive use (depletion) range from 25 to more than 50 percent of the water withdrawn in the Great Basin and the Upper and Lower Colorado Regions. Much of the waste water from coastal cities in California is discharged to the ocean and conse- quently is not available for reuse without waste water reclamation facilities. Plan Response The needs for additional water for the urban areas are met in the framework plan by continuing over- draft of groundwater, by conversion of agricultural water as urban areas expand onto irrigated areas, by additional importation or diversions, by more effici. ent use of available water, by salvage, and by construction of desalting plants. The proposed im- portation of Colorado River water into central Arizona will not be sufficient to eliminate overdraft. The transfer of water from northern California to 41