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Mr. BURLESON. There may arise the question as to what would be increased agricultural competition if a great many acres were put into cultivation on the Mexican side.

I am not too familiar with the area contiguous to the project, but my general impression is that in the immediate area, it is not conducive to tillable soil anyway. It is rather rough country, is it not? Mr. FISHER. Until you get down in the lower areas toward the Gulf.

Mr. Kilgore could probably elaborate on that, but I think it should be pointed out in response to your question that the Mexican Government insists upon conservation storage being in this project, and after all, the international agreement calls for that. That is the chief reason why conservation storage is included.

So, certainly if for no other reason, it is essential that we have it in collaboration with the Mexican Government and in accordance with the treaty agreement.

Mr. BURLESON. Mr. Chairman, I compliment my colleague on a very forceful and influencing statement.

Mr. FISHER. Thank you.

Mr. SELDEN. As the gentleman from Texas, Mr. Burleson, pointed out, we have a third extremely able member of the Texas delegation here today who is doing a very fine job for his constituency and State, Mr. Kilgore. Congressman Kilgore has indicated to me that he would like to be recognized later.

We will be glad to hear from you now, however, if you have any questions you would like to ask at this time.

Mr. KILGORE. Thank you, Mr. Chairman.

In the interests of conserving the committee's time, I think it would be better for me to wait until later when my constituents testify. Mr. SELDEN. Thank you. We will respect your wishes.

We have as our next witness, Col. L. H. Hewitt, Commissioner of the U.S. Section of the International Boundary and Water Commission.

If you will come up and have a seat, Colonel Hewitt, we will be glad to hear you.

STATEMENT OF COL. LELAND H. HEWITT, COMMISSIONER, U.S. SECTION, INTERNATIONAL BOUNDARY AND WATER COMMISSION, UNITED STATES AND MEXICO

Colonel HEWITT. I would like to present to the committee, Mr. Chairman, my able assistant, Mr. Joseph F. Friedken, who is the supervising principal engineer of the U.S. Boundary and Water Commission, who will assist me in pointing out on the map some of the things which we can do with this project.

A statement which I have prepared and which is already in the hands of the chairman and the members of the committee, I would like to read to emphasize some of the points which have been referred to by Mr. Fisher and undoubtedly will be referred to by others.

AUTHORIZATION

Authorization for this dam is contained in article 5 of the 1944 Water Treaty between the United States and Mexico, relating to the utilization of waters of the Colorado and Tijuana Rivers and of the Rio Grande, and provides in part:

The two Governments agree to construct jointly, through their respective Sections of the Commission, the following works in the main channel of the Rio Grande (Rio Bravo):

(I) The dams required for the conservation, storage, and regulation of the greatest quantity of the annual flow of the river in a way to insure the continuance of existing uses and the development of the greatest number of feasible projects, within the limits imposed by the water allotments specified.

(II) *** One of the storage dams shall be constructed in the section between Santa Helena Canyon and the mouth of the Pecos River; one in the section between Eagle Pass and Laredo, Texas (Piedras Negras and Nuevo Laredo in Mexico); and a third in the section between Laredo and Roma, Texas (Nuevo Laredo and San Pedro de Roma in Mexico). One or more of the stipulated dams may be omitted, and others than those enumerated may be built, in either case as may be determined by the Commission, subject to the approval of the two Governments.

*** The works shall begin with the construction of the lowest major international storage dam ***. The lowest major international storage dam shall be completed within a period of eight years from the date of the entry into force of this Treaty.

The lowest storage dam-Falcon Dam, located 75 miles downstream from Laredo, Tex.-was completed in 1953.

The proposed Amistad Dam and Reservoir, at a site 300 miles upstream from Falcon Dam and 1 river mile below the mouth of the Devils River, would be the second of the major international storage dams provided for by the treaty.

I might say in view of the fact that the actual site finally chosen for the Amistad Dam did not come within the three stretches of the river mentioned in the treaty, it was desirable that the committee approve the site of the Diablo, or the Amistad Dam, in its new location.

LOWER RIO GRANDE

The lower Rio Grande is a river which has, as Mr. Fisher said, a very long course. It rises in southern Colorado and flows in a southerly direction through the U.S. territory until it reaches El Paso, Tex., where it becomes the boundary between the United States and Mexico for about 1,250 miles to the mouth of the river.

About 80 miles downstream from El Paso, near Fort Quitman, Tex., the river enters into a canyon section, which marks the division point between the upper and lower Rio Grande.

The portions of the 1944 water treaty concerning the allocation of waters, control and regulation of the Rio Grande relate to the 1,170 miles of river below Fort Quitman.

From Fort Quitman to the site of the proposed Amistad Dam and Reservoir, a distance of about 600 river miles, the Rio Grande flows through the mountainous Big Bend section following a tortuous course through a series of deeply incised picturesque gorges and canyons separated by narrow intermontane valleys. The climate is arid. Developments along this section of the river are relatively small, consisting of a few communities and ranches with total population of

about 12,000, and scattered irrigated lands totaling about 14,000 acres along the U.S. bank and about the same along the Mexican bank. Cotton and feed crops are predominant.

From the Amistad dam site to Falcon Dam, a distance of some 300 miles, the river flows in a flood plain, generally one-half to a mile wide, bordered by hills and benchlands. The climate is semiarid. In this section are the border cities and trade centers of Del RioCiudad Acuna, Eagle Pass-Piedras Negras, and Laredo-Nuevo Laredo. Those on the U.S. side, together with smaller communities, have an aggregate population of about 120,000; those on the Mexican side about 100,000. Approximately 66,000 acres of land are under irrigation on the U.S. side, principally on the low benchlands in the vicinity of Eagle Pass. A similar acreage is under irrigation on the Mexican side. Cotton and feed are the major crops, and some vegetables are produced.

Below Falcon Dam, the river follows a meandering course, about 270 miles in length, through its delta section to the Gulf of Mexico. In this section, the lower Rio Grande Valley, the broad fertile lands on each side of the river have been developed, with the semitropical climate and with water from the Rio Grande for irrigation, into one of the most highly productive agricultural regions on the North American continent. On the U.S. side there are about 750,000 acres under irrigation, which support directly or indirectly some 360,000 people located in the cities of Brownsville, Harlingen, McAllen, San Benito, Edinburg, Mission, and Mercedes, and in other smaller communities, settlements, and rural areas. There are similar developments on the Mexican side.

The flow of the Rio Grande above Fort Quitman is largely controlled by storage reservoirs in the United States and releases are diverted for irrigation use. For the most part only drainage and irrigation waste waters pass Fort Quitman. Downstream from Fort Quitman tributary inflows, the major portion uncontrolled, from some 150,000 square miles of drainage area in the two countries, make up the riverflows. By the terms of the 1944 water treaty each country is generally allotted the inflows of its principal tributaries except that one-third of the inflows from the principal Mexican tributaries above Falcon Dam are allotted to the United States; and one-half of all other flows reaching the main channel are generally allotted to each country.

Three of the principal and greatest flood-producing tributaries enThe report submitted by the U.S. Section of the Commission had a out of Mexico near the town of Presidio, Tex., and the Pecos and Devils Rivers from the United States, just above the dam site and above Del Rio, Tex. At the damsite, average annual riverflows are expected to amount to 2,290,000 acre-feet, including 1,490,000 acrefeet of waters allocated by the treaty to the United States, which comprise about 80 percent of the total waters of the river allocated to this country.

Downstream from the Amistad site to Falcon Dam, a number of smaller tributaries pour into the river from each side, the largest of which, the Rio Salado from Mexico, discharges into Falcon Reservoir. Average annual flows expected to reach Falcon Dam under existing conditions of development amount to 2,890,000 acre-feet. Down

stream from Falcon Dam there are no live tributaries from the United States, but there are two major tributaries from Mexico, the Rio San Juan and the Rio Alamo. The estimated average annual total inflow to the Rio Grande below Fort Quitman, under existing conditions of development, is estimated to amount to 3,500,000 acre-feet.

The riverflows, derived from highly variable precipitation, vary erratically over wide ranges from year to year, from month to month, and even from day to day. On June 25, 1954, the river carried less than 2,000 cubic feet per second at Del Rio, and 3 days later the river rose 30 feet and carried a flood flow of 1,140,000 cubic feet per second from the Pecos and Devils Rivers, at the same location. The historic pattern of the natural flows of the Rio Grande is characterized by the occurrence of extremely high floods which cause widespread damage, separated by long periods-up to 11 consecutive years of subnormal flows when water shortages are suffered.

Thus, along the Rio Grande from Fort Quitman to the Gulf of Mexico, a distance of 1,170 miles, cities, towns and communities in the two countries aggregating some 900,000 people, 492,000 in the United States, and irrigation developments in the two countries totaling about 1,400,000 acres, 830,000 in the United States, are dependent upon control and regulation of the river's floods.

EXISTING PROJECTS

To alleviate the flood problem in the lower Rio Grande Valley, the two governments adopted in 1935 a coordinated plan for levees and off-river floodways in each country. Completed works, consisting in the United States of 88 miles of river levees and 137 miles of leveed interior floodways, afford protection against ordinary floods.

Completion of Falcon Dam in 1953, the first of the major international storage dams, provided a reservoir in the main channel of the river of a total capacity of 4,150,000 acre-feet, consisting of 1,710,000 acre-feet for control of floods and 2,440,000 acre-feet for conservation and silt storage capacity for the two countries. River floods reaching the dam are in a large part, though not entirely, controlled, reducing the frequency of major floods in the lower valley. However, major floods may still be expected in the valley from the two large Mexican tributaries to the river below Falcon Dam, and from spills at the dam. Falcon Reservoir, to the extent of its conservation capacity, divided 58.6 percent to the United States and 41.4 percent to Mexico, regulates the flood waters for domestic and irrigation use by the two countries in the lower valley. Also at Falcon Dam, hydroelectric energy is generated incidental to releases for irrigation. The energy is divided equally between the two countries.

Existing projects therefore afford the lower Rio Grande Valley a large measure of relief from floods and regulation of riverflows.

NEED FOR SECOND MAJOR INTERNATIONAL DAM

No works have been provided for control of floods above Falcon Reservoir. In the upper section from Fort Quitman to the Amistad Dam site, developments, though significant, are relatively small. But in the 300-mile middle section from the dam site to Falcon Dam,

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wherein are situated the adjoining border cities of Del Rio-Ciudad Acuña, Eagle Pass-Piedras Negras, and Laredo-Nuevo Laredo, floods affect directly or indirectly on the U.S. side alone, about 120,000 people, irrigated lands amounting to 66,000 acres, and main rail and highway communication systems in the area, including 5 international bridges across the river. The need for protection of the welfare and economy of U.S. interests in this section was demonstrated and emphasized by the 1954 flood which originated just upstream from the Amistad Dam site on the watershed of the tributary Devils and Pecos Rivers, had a peak discharge of 1,140,000 cubic feet per second at Del Rio, and caused damages along the U.S. bank amounting to $18.6 million. On the Mexican bank even greater damages were suffered and there was an undetermined loss of life.

Below Falcon Dam no damage was suffered from the 1954 flood, but only because the reservoir was practically empty at the time of its occurrence. However, in 1958 a flood occurred below Falcon Dam, due to a combination of spills at the dam and floodwaters from the Rio San Juan resulting in a peak flow of 100,000 cubic feet per second. Damages in the United States in the lower Rio Grande Valley were estimated to amount to a total of $9.5 million, of which $5.5 million were due to floodwaters which originated above the site of Amistad Dam and spilled at Falcon Dam.

Thus in two recent floods alone-1954 and 1958-U.S. interests suffered flood losses totaling $24.1 million (nearly one-half the U.S. share of the cost of the Amistad project).

The records, beginning in 1900, show that 16 other floods originated above the Amistad Dam site and caused damages in the middle section, and that a number of floods would have spilled at Falcon Dam to cause damage in the lower valley. Estimates indicate that in the event of recurrence during the next 59 years of floods in the middle section of the river, such as have occurred since 1900, without upstream flood control works, the damages to interests in the United States would amount to $110 million, and average $1,864,000 annually. The report submitted by the U.S. Section of the Commission had a somewhat different figure. These are revised figures, bringing the report up to date.

The U.S. need for additional conservation storage on the Rio Grande as contemplated by the 1944 water treaty, for the optimum feasible regulation of the riverflows, is evidenced by the experience that following completion of Falcon Dam in 1953, the extensive irrigation development in the lower Rio Grande Valley of Texas, which has an average annual water requirement of about 1,531,000 acre-feet, suffered critical water shortages in 1956 and 1957. Yet, just 2 years before, incident to the 1954 flood, the United States lost nearly 1 million acre-feet of its waters, which could have been saved to alleviate, if not eliminate, the 1956-57 shortages, had storage capacity been available at the Amistad Dam site. Moreover, in 1958, following the water shortage, nearly 2 million acre-feet of floodwaters allotted to the United States were spilled at Falcon Dam and lost to the Gulf of Mexico. The estimated value of U.S. water lost in 1954 and 1958 amounts to more than $60 million.

Studies based upon recorded flows of the past 59 years indicate that with Falcon alone, shortages of U.S. waters may be expected during 22 years of a 59-year period like that of record, in

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