The first of these basin reports-covering the Missouri River Basin was presented to the Congress last year (S. Doc. 191). Further studies of projects and sub-basins in the Missouri Valley are continuing. Reports on other major western river basins in various stages of completion by the Bureau are: Columbia River Basin, Rogue River Basin, Central Valley, Santa Barbara County, Russian River Basin, Lower Colorado River Basin, Upper Colorado River Basin, Great Salt Lake Basin, Nueces River Basin, Rio Grande Basin, Red River Basin, Pecos River Basin, Guadalupe River Basin, Colorado River (Texas) Basin, and Arkansas River Basin.

SPECIAL STUDIES TO AID SETTLERS

In addition to these basin reports and studies of individual projects in the postwar inventory, the Bureau brought to substantial completion during the year its special studies of the two largest Reclamation projects on its postwar development schedule, the Columbia Basin project in south-central Washington and the Central Valley project in California.

Published during the year were 3 of the 28 special reports prepared by the Columbia Basin Joint Investigations Committees-Types of Farming, Rural Recreational Areas, and Insuring Proper Land Use. Additional studies in the series are scheduled for publication during the coming fiscal year.

Also completed during the year were similar special studies for aid to settlers on the Central Valley project. The studies embrace a great volume of factual material on all phases of the proposed development of the project and were prepared by the Bureau in cooperation with a great many Federal and State agencies. Publication of some of the Central Valley studies is also planned for next year.

CONSTRUCTION ACTIVITIES LIMITED

Construction activities of the Bureau continued during the year on a restricted basis, confined almost entirely to projects under war food and war power programs.

The 37-mile Madera Canal on the Central Valley project was completed late in the fiscal year. It will provide water for irrigating about 20,000 acres of new land and supplemental water for 80,000 acres in the fertile San Joaquin Valley. An application to start construction on the 160-mile Friant-Kern Canal was pending before the War Production Board. Twenty-nine projects were cleared under the war food program.

Ten dams were partially completed at the end of the year, as follows:

A total of 144 miles of transmission lines was completed and construction of an additional 308 miles was in progress. Fifty miles. of canals were built and work on other water distribution facilities for war food production was continued. Construction during the year involved the use of more than 300,000 barrels of cement, and 220,000 cubic yards of concrete were placed. Construction of Anderson Ranch Dam on the Boise project in Idaho passed the half-way mark. When completed it will be the highest earthfill dam in the world. The reservoir created will provide flood control, and store irrigation water for 290,000 acres now receiving an inadequate supply. On the Deschutes project in Oregon an earth dam is under construction to provide irrigation for approximately 20,000 acres, and construction also was continued on the canals and distribution system for irrigating 32,000 acres on the Yakima Roza project in Washington.

Clearance was granted for the installation of additional equipment for the power plant and for emergency repair work on the spillway bucket at Grand Coulee Dam. On the Tucumcari project in New Mexico, work was completed on the first section of the Conchas Canal to provide irrigation water for an initial block of 7,000 acres.

Construction also progressed on the Gila project in Arizona and on the Coachella Canal in Southern California. Other construction included guniting over the dry rock paving in the desilting basins at the headwaters of the All-American canal, preparation of the designs. and specifications for the construction of the $17,000,000 San Diego Aqueduct, continued construction on the Salt Lake Aqueduct, flood control work on the Colorado River, and concrete lining work on the 13-mile Alva B. Adams Tunnel under the Continental Divide.

A limited program of construction was also carried on at Green Mountain and Shadow Mountain Dams on the Colorado-Big Thomp

son project in Colorado, and on the following projects cleared for construction under the war food program: Rapid Valley, S. Dak., Newton and Scofield, Utah, Mirage Flats, Nebr., Mancos, Colo., and Lugert-Altus, Okla.

DESIGNS PREPARED FOR POSTWAR PROJECTS

The Branch of Design and Construction concentrated on the preparation of designs for postwar projects, so that work might begin on a considerable volume of construction whenever war conditions permit. In planning for this postwar development of land and water resources, preliminary designs and estimates were made for 15 concrete and 10 earth dams, 40 power plants, 9 pumping plants, 2 water supply systems, and for canals and water distribution facilities on 15 projects. In addition to these, design studies were started on features of numerous other postwar Reclamation projects.

Primarily, construction work on projects authorized by the War Production Board has been for the purpose of food and power pro duction. The War Production Board authorized work on 21 Bureau projects during the fiscal year, but due to labor and materials shortages, some projects did not progress as planned. Efforts to conserve critical war materials has resulted in increased construction costs on some project features and at times has necessitated design changes.

TECHNICAL ADVANCES

Outstanding technical advances included the development of the hollow-jet regulating valve, and the development of the transformer reactance voltage-drop compensator. The hollow-jet valve will provide more economical installation and maintenance and improved operation for water outlet regulation. The voltage-drop compensator permits the adjustment of electric potential measuring devices in about one-tenth the time required by previous methods. During the year an inexpensive integrating machine was developed which will materially facilitate computations for design where differential equations are involved and which has possibilities for application in mathematical studies elsewhere.

BUREAU AIDS OTHER UNITED STATES AGENCIES

During the war, Bureau engineering and laboratory personnel and facilities were called upon to assist the War and Navy Departments, as well as other Government agencies and private corporations concerned with the war program, in solving a wide diversity of numerous technical engineering problems.

The Bureau cooperated with the Bureau of Mines by furnishing power for research, and with the Geological Survey in exploration for

strategic minerals, by providing technical assistance and laboratory facilities. The Bureau cooperated also with the War Department, the Geological Survey, and the Department of Agriculture in the interchange of information and technical data.

WORLD'S BIGGEST DAMS

The engineering accomplishments of the Bureau of Reclamation are known the world over. Its engineers have tamed the mightiest rivers in the West and put them to work at transforming barren lands into productive farms and to producing power for industry. The three biggest concrete dams in the world have been built by the Bureau of Reclamation-Grand Coulee Dam on the Columbia River in Washington, Shasta Dam on the Sacramento River in California, and Boulder Dam on the Colorado River between Arizona and Nevada.

The Bureau has built 15,495 miles of irrigation canals-enough to cross the continent five times. The storage reservoirs behind its dams have a capacity of 66,558,840 acre-feet. It has built 347 tunnels with a combined length of 560,271 feet. Operating on its projects are 31 hydroelectric plants with an installed capacity of 2,439,300 kilowatts, part of the energy produced being marketed over 2,164 miles of transmission lines built by the Bureau.

In the construction of its projects the Bureau has excavated 606,313,120 cubic yards of earth and rock, poured 33,671,861 cubic yards of concrete, used 38,289,133 barrels of cement. It has built 209,016 canal structures, 5,196 miles of waste water ditches and drains, 13,676 bridges, 23,620 culverts, 6,310 flumes with a combined length of 873,989 feet, and 331 pumping plants.

OPERATION AND MAINTENANCE PROGRAM

Operation and maintenance activities on the 52 operating Federal reclamation projects were devoted first and foremost to furnishing the irrigation service needed to maintain record-breaking agricultural crop production. The stabilization of these projects to protect the Federal investment is important, as are also steps which have been taken to aid in assuring the success of the water users through improved irrigation practices, land-use and related activities, including settlement.

A special effort was made again during the year to provide for the full use of Reclamation withdrawn lands for grazing purposes to support the livestock production in the West.

Activities carried on in the field by this branch of the Bureau of Reclamation for the benefit of water users and to facilitate project

operations included: (a) programs for improved operations of projects and preparations for operations, land use, and settlement on projects under construction or authorized; (b) land reclassifications; (c) thorough economic analyses in connection with the negotiation of amendatory repayment contracts and the deferment of construction charges. Plans for the land purchase, development and settlement of the Columbia Basin project were a major goal. Cooperation with State agricultural colleges and other agencies was advanced. Field work was completed or in progress on the reclassification of irrigable lands on 16 projects or divisions of projects, involving approximately 309,000 acres.

FIELD ORGANIZATIONS ESTABLISHED

Progress was made during the year in setting up operation and maintenance organizations in regional offices. This was in line with the decentralization program of the Bureau to place supervision and contacts closer to operations and to the water users affected, and also to prepare for accelerated operation and maintenance programs that will be needed with the end of the war in connection with project settlement.

The Operation and Maintenance branch was transferred from Denver to Washington during the year. The work of the branch has been primarily directed at (1) the delegating of direct supervisory responsibility of field operations to regional and project offices, (2) development of programs with emphasis on land-use and "the human side" of reclamation, particularly with respect to aiding veterans in settling on irrigated farms, and (3) the review of repayment contracts to determine the need for adjustment in repayment schedules, based on the ability of water users to meet such payments.

AMENDATORY REPAYMENT CONTRACTS

Section 17 (b) of the Reclamation Project Act of 1939 authorized temporary relief from payment of accrued construction charges for each of the years 1939 to 1943, inclusive, in cases where such payments could not be met due to circumstances beyond the control of water During the fiscal year, five water users' organizations submitted applications for relief from payments totaling $209,001.30. Four of the five requests concerned 1944 construction installments. No legislation existed for consideration of these requests until passage of Public Law 39 (79th Cong., 1st sess.) on April 24, 1945.

Action taken during the fiscal year to defer construction charge payments granted relief to five water users' organizations, for 1942 and 1943 installments, in the total amount of $208,214.41. Postponements of payments were recommended due to the critical finan