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Popular Science Monthly/Volume 61/August 1902/The Panama Route for a Ship Canal II

THE PANAMA ROUTE FOR A SHIP CANAL. II.
By Professor WILLIAM H. BURR,

COLUMBIA UNIVERSITY.

THE total length of the Panama route from the six-fathom curve at Colon to the same curve in Panama Bay is 49.09 miles. The general direction of the route in passing from Colon to Panama is from northwest to southeast, the latter point being about 22 miles east of the Atlantic terminus. The depression through which the line is laid is one of easy topography except at the continental divide in the Culebra cut. As a consequence there is little heavy work of excavation, as such matters go, except in that cut. A further consequence of such topography is a comparatively easy alignment, that is one in which the amount of curvature is not high. The smallest radius of curvature is 3,281 ft. at the entrance to the inner harbor at the Colon end of the route, and where the width is 800 ft. The radii of the remaining curve range from 6,234 ft. to 19,629 ft.

The following table gives all the elements of curvature on the route and indicates that it is not excessive:

Number of Curves. Length. Radius. Total Curvature.
Miles. Feet. °
1 0.88 19,629 1417
1 .48 13,123 1107
4 4.22 11,483 11131
15 11.61 9,482 35550
4 2.44 8,202 9020
2 1.67 6,592 7700
1 .73 6,234 3545
1 .82 3,281 7551
22.85 77139

Throughout the most of the distance between Colon and Bohio on the easterly side of the canal, the French plan contemplated an excavated channel to receive a portion of the waters of the Chagres as well as the flow of two smaller rivers, the Gatuncillo and the Mindi, so as to conduct them into the bay of Manzanillo, immediately to the east of Colon. That so-called diversion channel was nearly completed. Under the plan of the commission it would receive none of the Chagres flow, but it would be available for intercepting the drainage of the high ground easterly of the canal line and the flow of the two small rivers named, so that those waters would not find their way into the canal. There are a few other small works of similar character in different portions of the line, all of which were recognized and provided for by the commission.

The principal items of the total amount of work to be performed in completing the Panama canal, under the plan of the commission, can be classified as shown in the following table:

Dredging 27,659,540 cu. yds.
Dry earth 14,386,954 cu. yds.
Soft rock 39,893,235 cu. yds.
Hard rock 8,806,340 cu. yds.
Rock under water 4,891,667 cu. yds.
Embankment and back filling 1,802,753 cu. yds.
Total 97,440,489 cu. yds.
 
Concrete 3,762,175 cu. yds.
Granite 13,820 cu. yds.
Iron and steel 65,248,900 lbs.
Excavation in coffer dam 7,260 cu. yds.
Pneumatic work 108,410 cu. yds.

The lengths of the various sections of this route and the costs of completing the work upon them are fully set forth in the following table, taken from the commission's report, as were the two preceding:

Total Estimated Cost. Miles. Cost.
Colon entrance and harbor 2.39 $ 8,057,707
Harbor to Bohio locks, including levees 14.42 11,099,839
Bohio locks, including excavation .35 11,567,275
Lake Bohio 13.61 2,952,154
Obispo gates 295,434
Culebra section 7.91 44,414,460
Pedro Miguel locks, including excavation and dam .35 9,081,321
Pedro Miguel level 1.33 1,192,286
Miraflores locks, including excavation and spillway .20 5,781,401
Pacific level 8.53 12,427,971
Bohio dam 6,369,640
Gigante spillway 1,209,419
Pena Blanca outlet 2,448,076
Chagres diversion 1,929,982
Gatun diversion 100,000
Panama Railroad diversion 1,267,500
Total 49.09 120,194,465
Engineering, police, sanitation and general contingencies, 20 per cent 24,038,893
Aggregate $144,233,358

The item in this table called Panama railroad diversion affords provision for the reconstruction of the railroad necessitated by the formation of Lake Bohio. That lake would submerge the present location of the railroad for fourteen or fifteen miles.

It will be observed that in the estimates of cost of the canal on both the Nicaragua and the Panama routes 20 per cent, is allowed for 'engineering, police, sanitation and general contingencies.' For the purposes of comparison the same percentage to cover these items was used

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The Culebra Cut.

on both routes. As a matter of fact the large amount of work which has already been performed on the Panama route removes many uncertainties as to the character of material and other features of difficulty which would be disclosed only after the beginning of the work in Nicaragua. It has therefore been contended with considerable basis of reason that a less percentage to cover these uncertainties should be employed in connection with the Panama estimates than in connection with those for the Nicaragua route. Indeed it might be maintained that the exigencies which increase cost should be made proportional to the length of route and the untried features. On the other hand, both Panama and Colon are comparatively large centers of population, and, furthermore, there is a considerable population stretched along the line of the Panama railroad between those points. The climate and the unsanitary condition of practically every center of population in Central America and of the isthmus contribute to the continual presence of tropical fevers, and other diseases contingent upon the existing conditions of life. It is probable among other things that yellow fever is always present on the isthmus. Inasmuch as the Nicaragua route is practically without population the amount of disease existing along it is exceedingly small, there being practically no people to be sick. The initial expenditure for the sanitation of the cities at the extremities of the Panama route, as well as for the country between, would be far greater on the Panama route than on the Nicaragua. This fact compensates, to a substantial extent at least, for the physical uncertainties on the Nicaraguan line. Indeed a careful examination of all the conditions existing on both routes indicates the reasonableness of applying the same 20 per cent, to both total estimates of cost.

The preceding estimated cost of $144,233,358 for completing the Panama canal must be increased by the amount necessary to be paid for all the property and rights on the isthmus of the new Panama Canal Company. A large amount of excavation has been performed amounting to 77,000,000 cu. yds. of all classes of materials, and nearly all the right of way has been purchased. The new Panama Canal Company furnished the commission with a detailed inventory of its en tire properties, which the latter classified as follows:

1. Lands not built on.
2. Buildings, 2.431 in number, divided among 47 subclassifications.
3. Furniture and stable outfit, with 17 subclassifications.
4. Floating plant and spare parts, with 24 subclassifications.
5. Rolling plant and spare parts, with 17 subclassifications.
6. Plant, stationary and semi-stationary, and spare parts, with 25 subclassifications.
7. Small material and spare parts, with 4 subclassifications.
8. Surgical and medical outfit.
9. Medical stores.
10. Office supplies, stationery.
11. Miscellaneous supplies, with 740 subclassifications.

The commission did not estimate any value for the vast amount of plant along the line of the canal as its condition in relation to actual use is uncertain, and the most of it would not be available for efficient and economical execution of the work by modern American methods. Again, a considerable amount of excavated material along some portions of the line has been deposited in spoil banks immediately adjacent to the excavation from which it was taken, and would have to be rehandled in forming the increased size of prism contemplated in the commission's plan.

In view of all the conditions affecting it, the commission made the following estimate of the value of the property of the new Panama Canal Company, as it is now found on the Panama route:

Canal excavation $21,020,386
Chagres diversion 178,186
Gatun diversion 1,396,456
Railroad diversion (four miles) 300,000
$22,895,028
Contingencies, 20 per cent 4,579,005
Aggregate $27,474,033
Panama Railroad stock at par 6,850,000
Maps, drawings and records 2,000,000
Aggregate $36,324,033

The commission added 10 per cent, to this total 'to cover omissions, making the total valuation of the property and rights as now existing $40,000,000.' In computing the value of the channel excavation in the above tabulation it was estimated that 'the total quantity of excavation which will be of value in the new plan is 39,586,332 cu. yds.'

In January, 1902, the new Panama Canal Company offered to sell and transfer to the United States Government all its property and rights on the isthmus of every description for the estimate of the commission, viz., $40,000,000. In order to make a proper comparison between the total costs of constructing the canal on the two routes it is necessary to add this $40,000,000 to the preceding aggregate of $144,233,358, making the total cost of the Panama canal $184,233,358. It will be remembered that the corresponding total cost of the Nicaragua canal would be $189,864,062.

It is obvious that the cost of operating and maintaining a ship canal across the American isthmus would be an annual charge of large amount. A large organized force would be requisite, and no small amount of material and work of various kinds and grades would be needed to maintain the works in suitable condition. The commission made very careful and thorough studies to ascertain as nearly as practicable what these comparative costs would be. In doing this it gave careful consideration to the annual expenditures made in maintaining the various ship canals of the world, including the Suez, Manchester, Kiehl and St. Mary's Falls Canals. The conclusion reached was that the estimated annual costs of maintenance and operation could reasonably be taken as follows:

For the Nicaragua canal $3,300,000
For the Panama canal 2,000,000
Difference in favor of Panama $1,300,000
 

Much has been written regarding the comparative liability to damage of canal works along these two routes by volcanic or seismic agencies. As is well known, the entire Central American Isthmus is a volcanic region, and in the past a considerable number of destructive volcanic eruptions have taken place at a number of points. There is a line of live volcanoes extending southeasterly through Nicaragua and Costa Rica. Many earthquake shocks have occurred throughout Nicaragua, Costa Rica and the State of Panama, some of which have done more or less damage in large portions of those districts. At the same time many buildings, which have been injured, have not been

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Street in Panama.

substantially built. In fact that has generally been the case. Both routes lie in districts that are doubtless subject to earthquake shocks, but there is little probability that the substantial structures of a canal along either line would be essentially injured by them. The conclusions of the commission as to this feature of the matter are concisely stated in three paragraphs at the top of page 170 of its report:

It is possible and even probable that the more accurately fitting portions of the canal, such as the lock gates, may at times be distorted by earthquakes, and some inconvenience may result therefrom. That contingency may be classed with the accidental collision of ships with the gates, and is to be provided for in the same way, by duplicate gates.
 
PSM V61 D316 The bay and city of panama.png
Bay and City of Panama.
 

It is possible also that a fissure might open which would drain the canal, and if it remained open, might destroy it. This possibility should not be erected by the fancy into a threatening danger. If a timorous imagination is to be the guide, no great work can be undertaken anywhere. This risk may be classed with that of a great conflagration in a city like that of Chicago in 1871, or Boston in 1872.

It is the opinion of the commission that such danger as exists from earthquakes is essentially the same for both the Nicaragua and Panama routes, and that in neither case is it sufficient to prevent the construction of the canal.

The relative health fulness of the two routes has already been touched upon. There is undoubtedly at the present time a vast amount of unhealthfulness on the Panama route, and practially none on the Nicaragua route, but this is accounted for when it is remembered, as has also been stated, that there is practically no population on the Nicaragua route and a comparatively large population along the Panama line. There is a widespread, popular impression that the Central American countries are necessarily intensely unhealthful. This is an error, in spite of the facts that the construction of the Panama Railroad was attended with an appalling amount of sickness and loss of life, and that records of many epidemics at other times and in other places exist in nearly all these countries. There are the best of good reasons to believe that with the enforcement of sanitary regulations, which are now well understood and completely available, the Central American countries would be as healthful as our southern states. A proper recognition of hygienic conditions of life suitable to a tropical climate would work wonders in Central America in reducing the death-rate. At the present time the domestic administration of most of the cities and towns of Nicaragua and Panama, as well as the generality of Central American cities, is characterized by the absence of practically everything which makes for public health, and by the presence of nearly every agency working for the diseases which flourish in tropical climates. When the United States Government reaches the point of actual construction of an isthmian canal the sanitary features of that work should be administered and enforced in every detail with rigor of the most exacting military discipline. Under such conditions, epidemics could either be avoided or reduced to manageable dimensions, but not otherwise. The commission concluded that, 'existing conditions indicate hygienic advantages for the Nicaragua route although it is probable that no less effective sanitary measures must be taken during construction in the one case than in the other.'

The time required for passing through a trans-isthmian canal is affected by the length, by the number of locks, by the number of curves, and by the sharpness of curvature. The speed of a ship and consequently the time of passage is also affected by the depth of water under its keel. It is well known that the same power applied to a ship in deep water of unlimited width will produce a much higher rate of movement than the same power applied to the same ship in a restricted waterway, especially when the draft of the ship is but little less than the depth of the water. These considerations have important bearings both upon the dimensions of a ship canal and upon the time required to pass through it. They were most carefully considered by the commission, as were also such other matters as the delay incurred in passing through the locks on each line, the latter including the delay of slowing or approaching the lock and of increasing speed after passing it, the time of opening and closing the gates, and the time of emptying and filling the locks. It is also evident that ships of various sizes will require different times for their passage. After giving due weight to all these considerations it was found that what may be called an average ship would require twelve hours for passing through the Panama canal, and thirty-three hours for passing through the Nicaragua canal. Approximately speaking, therefore, it may be stated that an average passage through the former water-way will require but one third the time needed for the latter.

The time in which an isthmian canal may be completed and ready for traffic is an element of the problem of much importance. There are two features of the work to be done at Panama, each of which is of sufficient magnitude to affect to a controlling extent the time required for the construction of the canal, viz., the Bohio dam and the Culebra cut. Both of these portions of the work may, however, be prosecuted concurrently, and with entire independence of each other. There are no such features on the Nicaragua route, although the cut through the divide west of the lake is probably the largest single work on that route. In considering this feature of the matter it is well to observe that the total amount of excavation and embankment of all grades on the Nicaragua route is practially 228,000,000 cu. yds., while that remaining to be done on the Panama route is but little more than 97,000,000 cu. yds. or 43 per cent, of the former.

The commission has estimated ten years for the completion of the canal on the Panama route and eight years for the Nicaragua route, including in both cases the time required for preparation and that consumed by unforeseen delays. The writer believes that the actual circumstances attending work on the two routes would justify an exchange of these time relations. There is great concentration of work in the Culebra-Emperador cut, on the Panama route, covering about forty-five per cent, of the total excavation of all grades (43,000,000 cu. yds.), which is distributed over a distance of about seven miles with the location of greatest intensity at Culebra. This demands efficient organization and special plant so administered as to reduce the working force to an absolute minimum by the employment of machinery to the greatest possible extent. A judicious, effective organization and plant would transform the execution of this work into what may be called a manufactory of excavation with all the intensity of direction and efficiency of well-designed and administered machinery which characterizes the concentration of labor and mechanical appliances in great manufacturing establishments. Such a successful installation would involve scarcely more advance in contract operations than was exhibited, in its day, in the execution of the work on the Chicago Drainage Canal. By such means only can the peculiar difficulties attendant upon the execution of great works in the tropics be reduced to controllable dimensions.

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View on the San-Juan River in Nicaragua.

The same general observations may be applied to the construction of the Bohio dam, even should a no more favorable site be found.

The greatest concentration of excavation on the Nicaragua route is between the lake and the Pacific, but it constitutes only ten per cent, of the total excavation of all grades, and it can be completed in far less time than the great cut on the Panama route. If this were the only great feature of work besides the dam, the time for completion of work on this route would be materially less than that required for the Panama crossing. As a matter of fact there are a succession of features of equivalent magnitude, or very nearly so, from Greytown nearly to Brito, extending over a distance of at least 175 miles, requiring the construction of a substantial service railroad over a considerable portion of the distance prior to the beginning of work. This attenuation of work requires the larger features to be executed in succession to a considerable extent, or much duplication of plant and the employment of a great force of laborers, practically all of whom must be foreigners, housed, organized and maintained in a practically uninhabited tropical country where many serious difficulties reach a maximum. It is not within the experience of civil engineers to execute by any practicable means that kind of a program on schedule time. The weight of this observation is much increased when it is remembered that the total volume of work may be taken as nearly twice as great in Nicaragua as at Panama, and that large portions between Lake Nicaragua and the Caribbean Sea must be executed in a region of continual and enormous rainfall. It would seem more reasonable to the writer to estimate eight years for the completion of the Panama canal and ten years for the completion of the Nicaragua canal.

The prospective industrial and commercial value of the canal also occupied the attention of the commission in a broad and careful study of the elements which enter that part of the problem. It is difficult if not impossible to predict just what the effect of a trans-isthmian canal would be either upon the ocean commerce of the United States, or of other parts of the world, but it seems reasonable to suppose from the result of the commission's examinations that had the canal been in existence in 1899 at least 5,000,000 tons of the actual traffic of that year would have been accommodated by it. The opening of such a waterway, like the opening of all other traffic routes, induces the creation of new traffic to an extent that cannot be estimated, but it would appear to be reasonable to suppose that within ten years from the date of its opening the vessel tonnage using it would not be less than 10,000,000 tons.

The Nicaragua route would favor in distance the traffic between our Atlantic, including Gulf, and Pacific ports. The distances between our Atlantic ports and San Francisco would be about 378 nautical miles less than by Panama. Between New Orleans and San Francisco, this difference in favor of the route by Greytown and Brito would be 580 nautical miles. It must be remembered, however, that the greater time by at least twenty-four hours, required for passage through the Nicaragua canal, practically obliterates this advantage, and in some cases would throw the advantage in favor of the Panama waterway. This last observation would hold with particular force if for any reason a vessel should not continue her passage, or should continue it at a reduced speed during hours of darkness, which could not be escaped on the Nicaragua canal, but might be avoided at Panama. For all traffic between the Atlantic, including gulf ports, and the west coast of South America, the Panama crossing would be the most advantageous. As a matter of fact, while there may be some small advantage in miles by one route or the other for the traffic between some particular points, on the whole neither route would have any very great advantage over the other in point of distance or time; either would serve efficiently the purposes of all ocean traffic in which the ports of the United States are directly interested.

The effect of this ship waterway upon the well-being of the United States is not altogether of a commercial character. As indicated by the commission, this additional bond between the two portions of the country will have a beneficial effect upon the unity of the political interests, as well as upon the commercial welfare of the country. Indeed, it is the judgment of many well-informed people that the commercial advantages resulting from a closer touch between the Atlantic and Pacific coasts of the country are of less consequence than the unifying of political interests.

PSM V61 D321 Greytown harbor on the coast of nicaragua.png

The Breakwater of the Maritime Canal Company at the Former Entrance (now filled) to Greytown harbor on the coast of Nicaragua.

Concisely stating the situation, its main feature may be expressed somewhat as follows:

Both routes are entirely 'practicable and feasible.'

Neither route has any material commercial advantage over the other as to time, although the distance between our Atlantic (including Gulf) and Pacific ports is less by the Nicaragua route.

The Panama route is about one fourth the length of that in Nicaragua; it has less locks, less elevation of summit-level, and far less curvature, all contributing to correspondingly decreased risks peculiar to the passage through a canal. The estimated annual cost of operation and maintenance of the Panama route is but six tenths that for the Nicaragua route.

The harbor features may be made adequate for all the needs of a canal by either route, with such little preponderance of advantage as may exist in favor of the Panama crossing.

The commission estimated ten years for the completion of the Panama canal and eight years for the Nicaragua waterway, but the writer believes that these relations should be exchanged.

The water-supply is practically unlimited on both routes, but the controlling or regulating works, being automatic, are much simpler and more easily operated and maintained on the Panama route.

The Nicaragua route is practically uninhabited and consequently practically no sickness exists there. On the Panama route, on the contrary, there is a considerable population extending along the entire line, among which yellow fever and other tropical diseases are probably always found. Initial sanitary works of much larger magnitude would be required on the Panama route than on the Nicaragua, although probably as rigorous sanitary measures would be required during the construction of the canal on one route as on the other.

The railroad on the Panama route and other facilities offered by a considerable existing population render the beginning of work and the housing and organization of the requisite labor forces less difficult and more prompt than on the Nicaragua route.

The greater amount of work on the Nicaragua route, and its distribution over a far greater length of line, involve the employment of a correspondingly greater force of laborers with attendant difficulties for an equally prompt completion of the work.

The recent volcanic eruptions on the Island of Martinique indicate a possible, danger to the Nicaragua canal, should it be built, from the living volcano of Ometepe in Lake Nicaragua about ten miles from the land line. That there is some danger is beyond question, but it is very remote. There is no evidence to show that a canal or canal structure ten miles distant from Mount Pelee would have been injured by its recent eruptions, although navigation might have been interrupted for a short time. It is an open question, therefore, whether Ometepe in most violent eruption, even, would injure the Nicaragua Canal, although danger would exist.

On the other hand, as there is no volcano within about 175 miles of the Panama route, that route would be free from all danger of volcanic eruption.

Concessions and treaties require to be secured and negotiated for the construction of the canal on either route, and under the conditions created by the $40,000,000 offer for the new Panama Canal Company this feature of both routes appears to possess about the same characteristics, although the Nicaragua route is perhaps, freer from the complicating shadows of prior rights and concessions.