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THE COLUMBIA BASIN PROJECT

SUMMARY

The Columbia Basin project as considered in this report involves the construction of the following principal features:

(a) The Columbia River Dam, about 450 feet in height above the foundation, which, with appurtenant structures, will contain about 11,266,000 cubic yards of concrete and create a reservoir about 150 miles long, extending to the international boundary, the water surface of which will be about 355 feet above the low-water surface of the Columbia River.

(b) The Columbia River power plant containing an installation of turbines and generators of 2,100,000 horsepower capacity.

(c) The Columbia River pumping plant, containing an installation of motor-driven pumps of 16,000 cubic feet per second total capacity.

(d) A dam at each end of the Grand Coulee to form the Grand Coulee Reservoir about 23 miles long.

(e) Pipe lines leading from the Columbia River pumping plant to a supply canal 1.7 miles long which, in turn, leads to the north end of the proposed Grand Coulee Reservoir.

(f) An irrigation distribution system consisting of canals, tunnels, siphons, wasteways, bridges, head gates, etc., distributed over the main canal extending from the south end of the proposed Grand Coulee Reservoir, a distance of about 11 miles, from which point it branches into the main west canal and the main east canal. Each of these branch canals supply smaller canals equipped with suitable structures, the final reduction being to the size necessary to supply each 160-acre farm.

(g) Power plants and transmission lines at suitable places along the canals of the distribution system for the generation and distribution of about 26,000 kilowatts of seasonal power.

(h) Motor-driven pumping plants at suitable places along the canals to repump water a maximum of 100 feet to the various areas adjacent thereto.

(i) A drainage system to carry off seepage waters developed with the irrigation of land.

(j) Telephones and buildings necessary for the operation of the project and wells for water supply during the construction period. As a result of the construction of the foregoing items the following uses of power and water are proposed:

(a) The production at the power plant at the Columbia River Power Dam of 800,000 kilowatts of firm continuous power which will be available for commercial sale.

(b) The use of the secondary power generated at the Columbia River Dam to pump water from the Columbia River Reservoir to the

Grand Coulee Reservoir, the maximum difference of elevation between the surfaces of the two reservoirs being about 365 feet.

(c) The use of the water pumped into the Grand Coulee Reservoir to furnish an irrigation supply to 1,200,000 acres of land.

(d) The seasonal power generated at power plants at various drops on the project canals to be transmitted to pumping plants along the canals to lift water a maximum of 100 feet for irrigating 219,000 acres of the above-mentioned 1,200,000 acres.

The territory considered as the market area for the Columbia River power includes the area within a radius of 300 miles of the dam site embracing all of the State of Washington, the northern part of Oregon, the northern part of Idaho, and the western part of Montana. The present installed capacity of municipal and utility plants within this territory totals about 1,000,000 kilowatts, of which about 28 per cent is steam-electric power.

During 1920 to 1930 power requirements in this territory increased at an average rate of 9.5 per cent per year, compounded annually. For this report, a gradually decreasing rate of increase has been assumed beginning with 8 per cent in 1930 and decreasing to 4 per cent in 1960. Practically all of the power of the major hydroelectric developments on which construction has been started by the various power companies and municipalities will have been absorbed by 1940, which is the earliest date that power from the Columbia River development could be made available. The additional generating capacity required during the 15-year period 1940 to 1955 would amount to about 3,000,000 kilowatts whereas the proposed installation at the Columbia River Dam is 1,500,000 kilowatts or only one-half of the expected increase. With proper cooperation on the part of the various power companies and municipalities the proposed Columbia River development should be absorbed in this 15-year period.

Comparative estimates indicate that a price of 2.25 mills per kilowatt-hour should be sufficiently attractive to induce the power companies and municipalities to purchase energy in lieu of constructing additional power plants and to insure that the Columbia River power will be absorbed as rapidly as the growth of load will permit. Based on the absorption of 800,000 kilowatt of continuous power in 15 years, a price of 2.25 mills per kilowatt-hour for firm power, a price of $1 per acre per year for secondary power used for irrigation pumping, which is equivalent to approximately .5 mill per kilowatt-hour and land settlement at the rate of 20,000 acres per year, the revenue from power would be sufficient to repay the cost of the Columbia River Dam and power plant with interest at 4 per cent per annum in 50 years, in addition to providing for the operation, maintenance, and depreciation of the dam and power plant, and also provide a surplus of approximately $144,000,000 which would be available for repayment of the cost of the irrigation development and other purposes.

With the estimated surplus power earnings available for liquidating a portion of the irrigation investment, the annual construction charges to be paid by the land beginning four years after settlement and continuing for four years at a rate of $2 per acre and thereafter at $2.50 per acre for 32 years, will repay half of the cost of the investment in the irrigation project within 40 years from the time that water is available for each unit or division.

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The maximum estimated investment in the combined power and irrigation project up to the time when power revenues are sufficient to reduce the investment is $260,000,000.

CONCLUSIONS

1. The market for power in the territory tributary to the proposed Columbia River dam is sufficient to absorb the total firm power output to be generated at the Columbia River dam within 15 years after the dam is completed.

2. The time required to absorb the power output is a very important factor in the financial success of the proposed development. The power companies and municipalities operating power systems in the territory will have to cooperate to the fullest extent in the utilization of Columbia River power in order that it may absorbed as rapidly as possible.

3. The revenue which will be derived from the sale of commercial power at 2.25 mills per kilowatt-hour combined with the revenue from the sale of power for irrigation pumping at $1 per acre per annum will be sufficient to return within a period of 50 years the investment in the dam and power plant with interest at 4 per cent, to pay the cost of operation and maintenance of the dam and power plant, and leave a substantial surplus for repayment of a portion of the investment in the irrigation development.

4. The surplus from power revenues is estimated to be sufficient to repay within 40 years about 50 per cent of the cost of the irrigation development for the entire acreage of 1,200,000 acres proposed for the project or an average of over $85 per acre. The balance of the irrigation investment must be repaid by the lands or from other

sources.

5. Assuming the above surplus power revenues to be available, the total annual charge accruing against the land, beginning four years after settlement, would have to be $4.59 per acre, of which $2 per acre will be available for repayment of the investment in irrigation works. Beginning with the eighth year after settlment to the end of the fortieth year the annual charge must be increased to $5.09 per acre, of which $2.59 per acre will be available for repayment of the irrigation investment, without interest.

6. In order to reduce the annual charges for the irrigation benefits accruing against the land, it will be necessary that the State of Washington, municipalities, and all interests benefited within the irrigation district contribute toward the cost in proportion to such benefits.

7. Ultimate irrigation development is proposed for 1,200,000 acres. The slower the irrigation development proceeds the smaller the amount of additional funds that will have to be advanced from the Treasury of the United States.

8. In order to perfect final construction plans it will be necessary that further information be secured by diamond drilling of the foundation of the Columbia River dam; that additional field exploration and laboratory tests be made to determine the amount and source of supply of the concrete aggregates for the Columbia River dam; that a topographic survey and land classification be made of the irrigable area of the project; that test pits and borings be made to determine the classification of material to be excavated in the main canals of the project distribution system for use in final designs and estimates; and that a survey be made to determine the cost of irrigating land by pumping water from the Spokane River and using Columbia River dam power.

9. No construction on the Columbia River dam and power plant should be undertaken until contracts are executed for the sale of power which will insure sufficient revenue for annual expenses and the repayment of the investment in the dam and power plant with interest at 4 per cent within 50 years.

10. No construction on the irrigation development should be undertaken until the power revenues are assured and a suitable contract for repayment of the investment in irrigation works within 40 years has been executed by the district.

DESCRIPTION OF PROJECT

As considered in this report the proposed Columbia Basin project, located adjacent to and east of the Columbia River in eastern Washington, is a combination of power and irrigation development. The fundamental requisite for either power or irrigation is the construction of a dam in the Columbia River at the so-called Grand Coulee site shown on drawing No. 222-D-14. The Columbia River dam is to be 4,100 feet long and will raise the water about 355 feet above the low water surface of the river. It will create an artificial lake 150 miles long extending to the Canadian boundary line. The total height of the dam above the general elevation of the foundation will be about 450 feet.

Hydraulic and electrical machinery is to be installed progressively at the dam for the generation of power. It is contemplated that the firm power will be sold at the dam to responsible agencies engaged in the distribution of electrical energy. Pumping machinery for irrigation requirements is to be installed progressively at the dam and this machinery will utilize the seasonal power available during the high water season of the Columbia River.

Water for the irrigation project is to be pumped from the Columbia River reservoir through large discharge pipes to the Grand Coulee Canal extending a distance of 1.7 miles to Grand Coulee Lake. This lake will be created by the construction of two dams, one at the north end of the Grand Coulee near the Columbia River, and the other near the south end of the Grand Coulee about 411⁄2 miles north of Coulee City. This lake will be about 23 miles long and the difference between the high water surface in the Grand Coulee Lake and

the low water surface of the Columbia River reservoir will be about 362 feet.

From the south end of the Grand Coulee Lake, water is conducted through concrete lined canals, concrete lined tunnels, steel pipe siphons, and reinforced concrete pipe siphons to the lateral distribution system which finally delivers water to 981,000 acres of land, including that part of the area considered suitable for irrigation and cultivation. There are a number of places where the larger canals are dropped to lower elevations and the energy of the falling water at such places is to be utilized for repumping to areas lying at a maximum elevation of 100 feet above the canals. This repumping will add an additional irrigable area to the project of 219,000 acres making the total irrigable area of the project 1,200,000 acres.

PREVIOUS INVESTIGATIONS

The possibilities of irrigating the area along the Columbia River in Grant, Adams, and Franklin Counties in eastern Washington received consideration and investigation by the United States Reclamation Service as early as 1904. Surveys were made for canals using the Columbia, Spokane, and Palouse Rivers as sources of water supply. A total of $76,400 was spent on these early investigations. The Priest Rapids area was investigated in 1905 at a cost of $6,200.

Again in 1914 and 1915, under a cooperative agreement between the State of Washington and the United States Reclamation Service, an investigation and report was made on a proposed project north and east of Pasco, Wash., using the Palouse River as a source of water supply. This work was in charge of Engineer McCulloch and involved an expenditure by the United States Reclamation Service of $10.200.

Studies by the United States Reclamation Service on the possibilities of power development on the Columbia River at various times prior to 1923 involved an expenditure of $4,000.

The Columbia Basin commission of the State of Washington of which Marvin Chase, State hydraulic engineer, was chairman, and A. J. Turner, of Spokane, was chief engineer, published a report in 1920 as a result of its surveys and investigations in that year and in 1919. The commission investigated a number of plans for the project water supply, including several alternatives of a gravity supply diverting from Clark Fork at Albany Falls, a partial water supply from the Wenatchee River and a plan for pumping water from the Columbia River at the Grand Coulee site with a dam in the Columbia River 180 feet in height above low water.

A board of engineers of the United States Reclamation Service, consisting of D. C. Henny, James Munn, and C. T. Pease, reviewed the report of the Columbia Basin commission of the State of Washington in December, 1920. The report of this board suggested a number of changes in unit prices and recommended further investigations.

The State of Washington in 1921 made further investigations at the Columbia River dam site and explored the foundation by diamond drilling. Estimates were made of the costs of developing power, pumping water for irrigation, and building transmission lines at the Foster Creek site and also at the Grand Coulee site. The estimates and report of this work were prepared by Willis T. Batchellor,

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