1

templated in the power studies referred to in chapter VI. The structure is appropriately named for Arthur Powell Davis, whose name frequently recurs in this volume in connection with almost every phase of the Boulder Canyon project, the Colorado River Compact and the activities of the Reclamation Service, with which he was identified as engineer and Commissioner until his retirement in 1924. (2) Finding of feasibility, April 26, 1941 (appendix 1214).-Davis Dam was originally authorized by a secretarial finding of feasibility 1 under the authority of the Reclamation Project Act of 1939,2 section 9. It is under construction in the main stream of the Colorado River, at Pyramid Canyon, about 67 miles downstream from Hoover Dam and 34 miles west of Kingman, Ariz. It will be an earth and rock fill structure, having a volume of approximately 3,800,000 cubic yards, a maximum height of 138 feet above normal stream bed, and a crest length of 1,600 feet. It will create a storage reservoir with a total capacity of 1,820,000 acre-feet, of which 1,600,000 acre-feet will be "live" storage. A power plant, to be located on the Arizona side of the river, will have an installed capacity of 225,000 kilowatts, furnished by five 45,000 kilovolt-ampere generating units. The estimated output will be in excess of 800,000,000 kilowatt-hours annually. The transmission system will interconnect Davis, Parker, and Hoover power plants.

Construction was initiated in 1942, suspended because of the war, and resumed April 3, 1946.

(3) Davis transmission system.3. With the exception of two 69,000volt lines, one to Needles, Calif., and the other to Kingman, Ariz., all transmission circuits from Davis power plant will operate at 230,000 volts. Davis will be interconnected with both Hoover and Parker power plants and a line almost 300 miles in length will pass near Kingman and through Prescott and Mesa, east of Phoenix, to Coolidge where 115,000-volt extensions will connect with Tucson, Maricopa, Cochise, and other adjacent power markets in Arizona.

The transmission circuits from Davis power plant are tabulated in appendix 1215.

(4) Allocation of energy.-On June 23, 1948, Secretary Krug approved a tentative allocation of energy to be generated at Davis Dam. This appears herein as appendix 1216.

(5) Mexican treaty provisions.-The Mexican water treaty of February 3, 1944 (appendix 1405), obligated the United States (art. 12 (b)) to construct Davis Dam at its own expense within a period of

1 H. Doc. 186 (77th Cong., 1st sess.), reprinted herein as appendix 1214. 2 53 Stat. 1187.

3 For a description of Davis Dam and power plant and transmission lines now under construction, see hearings, House Committee on Appropriations, Interior Department appropriation bill, fiscal year 1949, p. 1188, et seq.

5 years from the date of entry into force of the treaty (November 8, 1945; see appendix 1406), and thereafter to

operate and maintain at its expense, the Davis storage dam and reservoir, a part of the capacity of which shall be used to make possible the regulation at the boundary of the waters to be delivered to Mexico in accordance with the provisions of Article 15 of this treaty.

Article 27 of the treaty suspended the provisions of articles 10, 11, and 15, covering the allocation and delivery of water to Mexico

during a period of five years from the date of entry into force of this treaty, or until Davis Dam and the major Mexican diversion structure on the Colorado River are placed in operation, should these works be placed in operation prior to the expiration of said period.

The Senate reservations of April 18, 1945 (see appendix 1405), recognized specific authorization in the treaty for expenditures for eight works, including

4. The Davis Dam and Reservoir mentioned in subparagraph (d) of article 12 of the treaty.

B. Parker Dam

Because of their close relationship to the Hoover Dam power contracts, the basic Parker Dam contracts are included in this volume. (1) Cooperative contract of February 10, 1933 (appendix 1201).-As part of its plans for the Colorado River aqueduct, the Metropolitan Water District considered, in the alternate, construction of a pumping plant in the vicinity of Parker, Ariz., or construction of a dam at that point to elevate and maintain a stable water surface. The United States had need for a reservoir at that point for reregulation of the river, and development of power for utilization on the Colorado River Indian Reservation, the Gila project in Arizona, and elsewhere in that State. The district and the United States entered into a cooperative contract on February 10, 1933 (printed herein as appendix 1201), under which the United States agreed, with funds provided by the district, to construct and operate the dam. The United States was to retain title and retain control over all water passing the dam. The district was accorded the right to divert water from the reservoir created by the dam and one-half the power privilege. The United States retained one-half the power privilege and the right to divert water from the reservoir for the Colorado River Indian Reservation, and for projects built under the reclamation law. The Government also secured the right, in this contract, to utilize excess capacity in the district's transmission system from Hoover Dam to Parker Dam.

(2) Litigation.-The State of Arizona resisted the construction of the dam, calling out its militia. In January 1935 the United States

commenced an original action in the United States Supreme Court to enjoin the State from interfering. The decision, rendered on April 29, 1935, refused the injunction on the ground that the Secretary of the Interior did not have adequate statutory authority (United States v. Arizona, 295 U. S. 174 (1936), appendix 1303).

(3) Legislation. The difficulty was removed by reauthorization of the project and confirmation of the 1933 contract, supra, in the Rivers and Harbors Act of 1935 (extracts from which are printed herein as appendix 1202).

Supplemental legislation, respecting compensation to Indians for rights-of-way, is cited in the margin.1

(4) Construction.-Construction of the dam was resumed after enactment of the Rivers and Harbors Act of 1935. The contractor and its engineer in charge, as at Hoover Dam, were Six Companies, Inc., and Frank Crowe. The dam is of the variable-radius-arch type, constructed of concrete, with a crest length of 800 feet, a base width of 100 feet, a top width of 50 feet, a maximum height above bedrock of 322 feet, and a volume of about 268,000 cubic yards. Because of the depth of the bedrock, upon completion three-fourths of the dam was below the bed of the river. The river level was raised only about 70 to 80 feet; but a reservoir, 28,000 acres in area with a capacity of 720,000 acre-feet, was created. This reservoir extends 45 miles up the Colorado and 5 miles up the Williams River.

The Parker power plant, as originally constructed, had space for four generators, with a rated capacity of 25,000 kilowatts each.

(5) Supplemental contracts.-FOREBAY CONTRACT (APPENDIX 1203): On September 29, 1936, the basic 1933 contract was supplemented by an agreement providing for the construction by the United States of a forebay and the power-plant substructure.

POWER-PLANT CONTRACTS (APPENDIX 1204): On April 7, 1939, the district and the United States entered into a contract providing for the construction of a power plant, and amending the contract of 1933 and

Act of July 8, 1940 (54 Stat. 744), in aid of the construction of the Parker Dam project, granted to the United States all interest of the Indians to tribal and allotted lands in the Fort Mojave Indian Reservation, Ariz., and the Chemehuevi Reservation, Calif., designated by the Secretary of the Interior, subject to determination of compensation by the Secretary, with the direction that the amount so determined should be paid to the Secretary by the Metropolitan Water District in accordance with the terms of the cooperative contract of February 10, 1933, for the construction of Parker Dam (appendix 1201). See Solicitor's opinions (unpublished), August 24, 1936, December 15, 1937, re Fort Mojave and Chemehuevi Indians, respectively. The act of October 28, 1942 (56 Stat. 1011), granted to the United States the interests of the Indians in lands acquired for construction, operation, and maintenance of transmission lines, the amounts found by the Secretary to be due to the tribes or individual allottees to be paid them from the funds available for the Parker Dam power project, or used for the acquisition of other lands.

that of 1936 (supra) in several respects. On July 10, 1942, by supplemental agreement, the contract of April 7, 1939, was amended. All of the operative parts of the 1939 and 1942 agreements appear in the amended text of the power plant contract of 1939 (printed herein as appendix 1204).

CHANGE OF SAN DIEGO DIVERSION POINT; SUPPLEMENTAL CONTRACT OF OCTOBER 1, 1946 (APPENDIX 1205): The inclusion of the San Diego County Water Authority in the district necessitated a change in the point of diversion of water for San Diego from that specified in the San Diego All-American Canal contract of October 2, 1934 (appendix 1111), to a point above Parker power plant. (See San Diego contracts of October 4, 1946 (appendix 1012), and March 14, 1947 (appendix 1014).) The effect of such added diversion was to diminish the power privilege at Parker Dam. The United States insisted that the district agree to hold the United States harmless against that reduction. This was done by contract dated October 1, 1946 (appendix 1205). To enable the district to comply with those requirements, a collateral agreement was made between the Edison Co. and the district for the replacement energy involved (omitted from this volume). The estimated present worth of the energy required to make good the depletion of the plant output was added to the amount payable to the district by the San Diego County Water Authority as a special tax.

FOUR-PARTY 1947 PARKER UNIT CONTRACT (APPENDIX 1206): The district's 1945 resale contract previously referred to (appendix 912) provided an absorption period with respect to the district's unused energy. By an agreement, dated May 20, 1947 (appendix 1206), the district agreed with the purchasers of its unused Hoover Dam energy to exercise its right to have units 3 and 4 of Parker power plant transferred to its service immediately after December 13, 1952, and thereafter to use Parker energy in preference to energy from Hoover Dam. This operation will have the effect of making more energy available for the purchasers of district unused energy at Hoover Dam. In consideration thereof the purchasers under the 1945 resale contract agreed to eliminate the advantage accruing to them by virtue of the absorption period stated in the 1945 agreement, so that, in effect, the district thereafter should suffer no loss on account of unused Hoover Dam energy.

(6) Operations.-Parker Dam power has proved an important source of energy for the central Arizona area, as well as Imperial Irrigation District, California. Provision is made in the Hoover Dam agency contract (appendix 902) and the energy contract with the Metropolitan Water District (appendix 905) for the integration of the various Government-owned power plants on the Colorado River, including Hoover and Parker Dams, and the utilization of the

district's transmission line between Hoover Dam and Parker Dam, in part.

7. Parker transmission system.--Whereas the bulk of Hoover power is at present transmitted to the western areas of southern California, most of the power from Parker and Davis power plants is being utilized in the States of Arizona and Nevada. From Parker power plant 161,000-volt transmission circuits serve the Central Arizona Light & Power Co. and the Salt River Valley Water Users Association in the Phoenix area, with a 115,000-volt extension from Phoenix to Tucson. Another line of similar voltage extends to Gila and Yuma for customers in that vicinity and thence into the Imperial Irrigation District of Southern California. In addition to these 161,000-volt circuits, a short 230,000-volt line connects the Parker plant with the Metropolitan Water District's system at Gene substation and a 69,000-volt line carries Parker power to the Bagdad Copper Co. in Arizona.

C. Colorado River Aqueduct

(1) Historical background.-The Colorado River aqueduct is one of the major water projects of the lower Colorado River Basin, dependent on Lake Mead for storage and Hoover Dam for power for pumping. It was constructed from 1933 to 1940 and has been operated since 1941 by the Metropolitan Water District of Southern California. This is an overlapping district composed of 16 member cities and water districts, organized in 1927, distributing wholesale municipal water supplies to 27 incorporated cities and their suburbs in Los Angeles, Orange, and San Diego Counties of southern California. The district has a present population of 3,500,000, grown from 2,350,000 since 1940 and from less than 150,000 in 1900. The project was financed by general obligation bonds which were held temporarily during the depression years by the Federal RFC, but were long ago resold to the investing public at a considerable profit to the United States.

(2) Government contracts.-As outlined in chapters VI and X, on April 24, 1930, the Metropolitan Water District of Southern California entered into a contract with the United States (appendix 1007) for the storage and delivery of 1,050,000 acre-feet annually and, on April 26, 1930, entered into a contract with the United States (tabulated in appendix 602; printed in full as appendix 3 to the first edition) for Hoover Dam power to pump water into and in its aqueduct. The water contract was amended on September 28, 1931 (appendix 1008), and the power contract on May 29, 1941 (appendix 905). The district's cooperative contract with the United States for the construction of Parker Dam, February 10, 1933 (appendix 1201), has been referred to, supra.