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COMMITTEE ON INTEROCEANIC CANALS,
UNITED STATES SENATE,
Washington, D. C., Tuesday, March 20, 1906. The committee met at 10.30 o'clock a. m.
Present: Senators Millard (chairman), Kittredge, Dryden, Ankeny, Morgan, Taliaferro, and Simmons.
FURTHER STATEMENT OF JOHN F. WALLACE, ESQ.
Senator KITTREDGE. Mr. Wallace, you testified before the committee some time ago regarding administrative matters.
Mr. WALLACE. Yes, sir.
Senator KITTREDGE. In that testimony you gave us the date when you first became connected with the canal as chief engineer.
Mr. WALLACE. Yes, sir.
Senator KITTREDGE. And you continued as chief engineer until what date?
Mr. WALLACE. Until June 29, 1905.
Senator KITTREDGE. About the 1st of April, 1905, you became a member of the Canal Commission?
Mr. WALLACE. Yes, sir.
Senator KITTREDGE. And continued in that capacity until the same date in June?
Mr. WALLACE. The same date; yes, sir. Senator KITTREDGE. So that in addition to your duties as chief engineer you were also a member of the Commission from about April 1, 1905, until June 29, 1905 ?
Mr. WALLACE. Yes, sir. After April 1, 1905, I was chief engineer, member of the executive committee, and Commissioner. About the 10th of April the Panama Railroad was put in my charge on the Isthmus as vice-president and general manager, but I was not able to assume charge of that road on the Isthmus until I returned there about the 25th of May, 1905.
Senator KITTREDGE. You have read the report of the Board of Consulting Engineers ?
Mr. WALLACE. I have. Senator KITTREDGE. And the views of the minority of that Board ? Mr. WALLACE. Yes, sir. Senator KITTREDGE. Will you please advise us of the type of canal which, in your judgment, ought to be recommended by this committee to the Senate for construction ?
Mr. WALLACE. Mr. Chairman, my single purpose in appearing before you at this time is to give you the very best judgment I have been able to form upon the two matters you are now considering and as to which I have, as you know, a very considerable knowledge. I need not repeat the experiences which I think justify me in speaking with some little authority upon the engineering problems before you, and I think I fully explained the somewhat exceptional practice I have had in dealing with large problems of construction similar in many respects to the problems confronting you in the matter of the Panama Canal.
I wish, therefore, simply as an American citizen, to put the judgment which I have formed on the basis of these experiences before you, and through you before the Congress, to assist in reaching what I am sure every member of it, of both parties, ardently desires to reach-a conclusion as to the best type of canal and the best method of doing the work involved in its construction. Of course I recognize that the committee may well differ from me and the majority of the Board of Consulting Engineers for the Panama Canal as to type of canal and may differ far more with far greater freedom as to the best method of constructing it, but I feel that I will have done my full duty when I have laid my views before you and given you, as far as I am able, the reasons upon which they rest in my own mind.
In considering the question of alternate plans for the canal, whether it should be upon a high level with locks, or upon a sea level without locks, my judgment as an engineer is controlled by several principles which commend themselves to me as really fundamental, and so far as I am concerned, conclusive.
In the first place it must be conceded that an approximately straight sea-level canal, of ample width and depth, is the best type of canal, and that any other plan which places restrictions upon the probable permanency of the canal itself, as well as upon the speed and the size and number of vessels passing through it, must necessarily render the canal far less valuable and far less desirable than if such doubt as to its permanency and such restrictions did not exist.
In the second place, it must be equally admitted that the only deterrent elements in accomplishing the more desirable result--that of the sea-level canal—are the two factors of relative time and cost, when this most desirable form is contrasted with the far less desirable form of a high-level canal with locks.
In the third place, it must be admitted that a very proper way to approach a discussion of the relative desirableness of these types would be to consider how much money the American people may be supposed to be willing to invest in the canal and how long they may be supposed to be willing to wait for its proper accomplishment.
After these important factors are determined the committee ought to be able to readily decide which of the two types of canal seems to it to be the better and to give its approval to the type it prefers.
Now, as to the cost. We have told the civilized world that the United States of America are willing to construct the Panama Canal for the benefit of the world and its commerce, including our own; and as we have voluntarily accepted this great duty, it is to be presumed that the people prefer that the Congress should approach it from a broad, general, and liberal standpoint, constructing the most permanent and best possible type of canal, rather than to offer to
the world an inferior type of doubtful permanency, especially as the best type of canal is one which, so far as can now be foreseen, will not have to be materially altered or enlarged and upon which our descendants may look with pride, with no occasion to regret any inefficiency or instability in the work due to our having been too careful of our money or too shortsighted in our engineering judgment.
The amount of tonnage which will pass through the canal when completed is, of course, largely a matter of conjecture, but it is certain that it will be large and ever increasing, and that considerable tonnage will be diverted from the Suez route. The phenomenal increase of tonnage passing year by year through the Suez Canal is a reasonable assurance that the continued prosperity and growth of the commerce of the world will justify the expenditure at Panama of the money required to give such commerce the best possible waterway between the two oceans. Judged by the capitalization and dividends now paid upon the stock of the Suez Canal it is apparent that the rates charged for transit through it are excessive, and on the assumption that the rates for passing through the Panama Canal will be considerably less, a very material saving will be offered to commerce if it takes the Panama route.
Assuming that the present amount of tonnage through the Suez Canal of, say, 10,000,000 tons per annum would pass through the Panama Canal, even at a dollar a ton, there would be an approximate income of $10,000,000, which is sufficient to justify an expenditure of $300,000,000. As the commerce passing through it will in the near future pay the interest upon the bonds issued to construct it, without taking into consideration any indirect commercial benefits which would accrue to this country, and without considering the advantages which would be derived from the canal in the improbable event of war, it would seem that an expenditure of $300,000,000, a sum ample to construct the sea-level canal, would be abundantly justified, considering the probable rapid development of foreign and domestic trade and the indirect results to be derived from this great waterway. Under these conditions the increased expense of constructing a sealevel canal ought not to weigh very heavily in deciding the question of type.
Now, as to the additional time required for a sea-level canal, it may be predicted with some certainty that upon a basis of reasonable energy and the use of proper business methods of administration a sea-level canal can be fully completed in ten, or, to be entirely safe, say twelve years, and a lock canal, even if only 60 feet above sea level, will require seven, or, to be entirely safe, say nine years, on the same basis of energy and administration—a difference of only three years. I make this concession out of abundant caution; but considering that the work on the sea-level canal is plain, ordinary, everyday work of digging and hauling away what is dug, I do not believe very much additional time would be required for the sea-level canal. It does not seem, therefore, that the additional time required for the sealevel canal should seriously militate against deciding upon that type.
It must also be remembered that it is quite possible to secure even increased efficiency over that assumed to be now probable in case the work should be handled by a single contracting firm, unhampered by governmental methods and with every incentive to expedite and complete the work at the earliest possible moment. Indeed, under such
conditions it is very probable that the period suggested could be considerably reduced. Instead of one shift of ten hours the contractor might utilize electric lights and work two shifts.
If it is not too much to hope that the committee will decline to recommend any form of canal which is not capable of being in the future transformed into a sea-level canal without undue interference with the world's traffic and without undue additional cost, this fact alone should take the recommendations of the minority of the board of Consulting Engineers and the recommendations of the majority of the Isthmian Canal Commission out of really serious consideration; for it is difficult to see why any type of canal should now be authorized the destruction of any important feature of which, either by act of God or of man, would block all use of it until its restoration, particularly when such interruption of traffic would almost certainly extend over several years and the world having become accustomed to its advantages would incur such a loss of time with the greatest possible sense of injury.
There is another engineering problem which ought to have careful consideration, and that is whether the Congress will feel justified in indorsing the construction of any dam of large dimensions retaining a head of water of, say, 85 feet, the foundation of which does not extend to bed rock or to some equally impermeable and reliable strata. The engineering question may be thus stated: Is it either sa fe or wise to authorize the building of a dam 1.1 miles long to retain a head of water of 85 feet across an alluvial valley similar to the valley of the Chagres at Gatun, in which exist already two subsurface gorges, one of which alone is 1,000 feet across and 240 feet deep, which has evidently been refilled with a heterogeneous mass of gravel, sand, sandy clay, driftwood, and the general character of detritus brought down into the valley by the mountain streams?
With this situation in view it is greatly to be feared that the dam at Gatun, which is proposed by a minority of the Board of Consulting Engineers and which is indorsed by a majority of the Isthmian Canal Commission, might after some years be found incapable of holding back so great a head of water and withstanding the strain upon it. This apprehension is greatly emphasized by the character of the borings in this locality, because they have not been sufficient to determine the accuracy of the cross section which has been submitted as one of the exhibits of the Board of Consulting Engineers to the Isthmian Canal Commission. Sand or gravel may even underlie the indurated clay into which borings have only been made a short distance. The same remarks apply, though in a lesser degree, to the series of dams and barrages holding back a head of 55 feet of water which it is proposed by the minority report to construct across the alluvial valley of the Rio Grande on the Pacific side of the canal.
From an engineering standpoint it is difficult to understand why a much better place for the construction of a dam to control and regulate the floods of the Chagres River is not at Gamboa where it is positively known that the primary rock foundation exists at no greater depth than sea level, and where it is possible to construct a masonry dam founded on solid rock at such a moderate depth and in accordance with established methods, that its integrity will no longer give rise to question.