"In the truest sense, the Pacific Northwest-Pacific Southwest Intertie is a conservation Stewart L. Udall Secretary, Department of the Interior E UNIVERSITY GINEERING United States Department of the Interior Bureau of Reclamation, Floyd E. Dominy, Commissioner Washington Office: United States Department of the Interior, Bureau of Reclamation, Washington, D.C., 20240. Assistant Commissioner.. Assistant Commissioner. N. B. Bennett, Jr. G. G. Stamm Assistant Commissioner. Chief Engineer, Denver, Colorado.. REGIONAL OFFICES REGION 1: Harold T. Nelson, Regional Director, Box 937, Reclamation Building, Fairgrounds, Idaho, 83701. W. P. Kane Issued quarterly by the Bureau of Reclamation, United States Department of the Interior, Washington, D.C., 20240. Use of funds for printing this publication has been approved by the Director of the Bureau of the Budget, January 31, 1961. For sale by the Superintendent of Documents, U. S. Government Printing Office, Washington, D.C., 20402. copy.) Subscription price: $1.00; 25 cents additional for foreign mailing. Price 30 cents (single ABOUT THE AUTHORS... The special articles on these pages were written by eminent scientists and technical leaders in the field of electric power and high voltage transmission. The six authors did very well in attempting to adapt technical language to terms understood by the average reader. The editor is indebted to these men for their efforts and hopes that the further simplification in final editing will not lead to an inaccurate impression of the subject they know so well. After noting this editor's confession to the problems involved in communication of a very complex subject, we hope even our most distinguished contemporaries will find interest at each turn of the page. This is a story of modern engineering achievement in our time. A New Power One of the key officials in planning and development of the Pacific Northwest-Pacific Southwest Intertie, Commissioner Dominy tells the story of the evolution of the transmission giant capable of carrying the output of two Grand Coulee Powerplants. Giant Materializes on the West Coast by COMMISSIONER FLOYD E. DOMINY THE HE Pacific Northwest-Pacific Southwest Intertie is the biggest single electrical transmission project ever undertaken in this country. Stretching from the Columbia River to Hoover Dam and Los Angeles, four big gleaming lines of the new system will carry more than 4 million kilowatts, southward or northward. This is the equivalent of the output of two present Grand Coulee Powerplants! The lines will tie together electric systems— public and private-all the way from Vancouver, B.C., and Seattle to Phoenix, Arizona, and California points, including the biggest Federal hydro system in America, the biggest municipal system, and the biggest group of private systems in the West. These systems are respectively: the Federal Columbia River Power System, the Los Angeles Department of Water and Power, and the private California Power Pool. The Intertie system will benefit the people in 11 western States, especially the customers of many small rural electric cooperatives, municipal systems and other public agencies-about 250 distributors in all. Also, it will reduce the waste of hydroelectric kilowatt-hours over dam spillways in the Pacific Northwest, and will promote a maximum of electrical efficiency throughout those States. Two of the four big Intertie lines will be direct current lines, America's first and the world's longest. This project will make our Nation the world leader in an exciting new transmission technique. Precedent Broken For many years there has been general agreement on the need for a great new power tie line in the far West. However, conflicts in regard to control and sharing of benefits long delayed progress on it. With the conflicts now largely resolved, the PNW-PSW Intertie has become a precedentbreaking joint endeavor of Federal, public and pri vate power organizations. In addition, area rights have been spelled out in special legislation, while agreements by agencies have been reached on the distribution of benefits to all power consumers. Construction is now in progress, and the first kilowatts will shoot through the new Intertie in late 1967. The primary purpose of the Pacific Intertie is to coordinate operation of all utility systems in the area so as to obtain maximum overall utilization and efficiency of the generating capacity. And even the smaller utilities, which might otherwise face strong economic competition, will receive maximum benefits. In the early years of the United States-Canadian Treaty, power from joint Upper Columbia River developments will be marketed in California, Nevada, and Arizona. This power will not only be available to the residents of those States who are increasingly using air-conditioning in their homes and offices, but the kilowatts also are now being contracted for by irrigators in the giant Central Valley Project, presently being enlarged and improved. The Bonneville Power Administration (BPA), which acts as a balance wheel in marketing Federal power in the Northwest, will give aid to other agencies, and will itself, receive aid. Bureau of Reclamation projects on the Colorado River almost completely control that stream for water and power production and are tied into a large power network of mainly steam-electric plants. In this regard, the Intertie will result in savings of installed steam-electric capacity, further use of surplus Northwest energy to save fuel, The giant structural webbing of this transmission facility luminesces startlingly beautiful at night. and power and energy exchanges from the Southwest to firm up capacity in the Northwest. Early Program Expands The earliest plans for a Federal transmission line between the BPA grid and the northern California systems envisioned the same important general purposes as today's larger PNW-PSW Intertie system. However, a greater load growth and technological advances of recent years have added other major uses to be considered, and have required redesigning of facilities. Where only one 230,000-volt line with a capacity of about 150 thousand kilowatts was planned back in 1935, four extra-high voltage lines are now being constructed with a total capacity of up to 4.6 million kilowatts. I remember in 1935, when Grand Coulee and Bonneville Dams were under construction, that there was talk about interconnecting electrical energy from those dams and non-Federal plants to California's Central Valley power, a few hundred miles south. It was anticipated that the Central Valley system would expand northward and meet the other grid part way. This idea was included in a report called "The Columbia Basin," 1935, by the Pacific Northwest Regional Planning Commission, a Federal agency. The possibility of such interregional movements of power also was discussed in a Corps of Engineers' Review Report on the Columbia River, published in 1948. "Such interconnections," the Engineers' report said, "will obtain economies from diversity of loads and streamflows and the exchange of surplus energy or power." Reclamation Finds Plan Feasible A report on the first detailed investigation of a possible intertie between the Bonneville (BPA) system and the Central Valley Project was released by the Bureau of Reclamation in 1949. The Bureau found that an interconnection to close the gap of 217 miles which then separated the two systems that is, from Roseburg, Oregon, to the Shasta switchyard-was economically feasible and desirable. Diversity of loads and resources made the Bonneville and Central Valley systems complementary. By a process of displacement from one area |