Pacific Southwest Water Plan August 1963

Document: "Pacific Southwest Water Plan- Corrected to 8/19" Chapter VI, August 19, 1964, page 4Southwest Water Plan incorporates individual projects designed to accomplish the overall objective. This Plan proposes facilities for needed water supply developments in an orderly sequence by phases for the benefit of Arizona, California, Nevada, New Mexico, and Utah. Construction would need to proceed concurrently in these States to provide the required water service. The proposed construction schedule is programed over approximately 35 years. Proposals for implementation of the Plan of Development are discussed in detail in Chapter VIII. Phase I - Immediate-Action Program--The Immediate-Action Program includes the following projects and programs: The Central Arizona Project Aqueduct system, is proposed for construction to bring a portion of Arizona's available mainstream Colorado River water to the rapidly expanding metropolitan areas of Phoenix and Tucson. In addition, water would be delivered to several agricultural areas which now depend on the declining ground-water basins in Maricopa and Pinal Counties. The facilities described in detail in the 1947 report on the Central Arizona Project, House Document No. 136, 81st Congress, 1st Session, have been modified to reflect present conditions and changed demands in the service area. A supplemental report has been prepared and current cost estimates reflect these changes. The initial capacity of the system would be capable of a normal diversion of 1,200,000 acre-feet of water per year and, under overloaded conditions, could divert water at a rate aggregating 1,450,000 acre-feet per year to the service area when additional supplies are available. Direct deliveries would be used to supply both supplemental and exchange water. Since the present ground-water overdraft exceeds the import capability of this system, the overdraft would continue in the Central Zone but at a reduced rate. The constantly increasing municipal and industrial demands would be satisfied in the future by additonal works provided for in Phase II. Enlargement of the California Aqueduct for conveying an additional water supply of 1,200,000 acre-feet to Southern California is included in Phase I. This conveyance capacity which is additive to the basic California Aqueduct would permit conveyance of limited surplus Sacramento-San Joaquin River Delta water upon completion of construction. Firm water supply for this incremental aqueduct capacity would be provided by the proposed storage reservoirs on Trinity River in Phase II. The additional supply conveyed through the proposed aqueduct enlargement would provide replacement water for a decreasing Colorado River supply as well as water for the projected growing demand beyond that which will be met by the presently designed California Aqueduct. Also included in Phase I is a second incremental enlargement of the California Aqueduct through the Tehachapi Mountain reach to the location where the Havasu Aqueduct proposed in Phase II bifurcates. This additional enlargement contemplates importation of a second unit of 1,200,000 VI-4Epson Perfection 4870 Photo, 400 dpi, 8 bit, 1,413,992 byte