Much has been written and said about the need for a new canal to connect the Pacific and Atlantic Oceans. World-wide maritime interests are awaiting the accomplishment with understandable interest.
The U. S. Congress and President L. B. Johnson’s administration have expressed a need to move as expeditiously as possible toward construction of a sea-level canal somewhere in Latin America. A commission that was created by Congress in 1964 is to come up with its conclusions and recommendations by the end of June 1968.
The need for a new canal is not so much related to heaviness of traffic or congestion as it is to a canal with greater dimensions. It will be many years before real congestion will set in on the Panama Canal, if ever. When we compare the time for rounding South America with the time for transit of the existing Panama Canal (approximately 8 hours), the latter time can be multiplied many times before a real basis for complaint due to congestion will exist. The problem is to meet the needs of the larger and larger ships that are now either plying the oceans, or are under construction, or in the planning stage somewhere in the world today.
The Suez Canal is about to be deepened and widened, according to recent announcements by Gamal Abdel Nasser, President of the United Arab Republic. The project for such improvement of the Suez, a sea-level canal, and therefore without locks, should be much simpler than improvements for the Panama Canal; although much of the Suez Canal, over its slightly more than 100-mile course between the Red Sea and the Mediterranean Sea, is through shifting sands that create difficulties in maintenance.
The permissible draft of ships now passing through the Suez is up to 36 feet under normal circumstances. Under special circumstances involving primarily the design of the vessel, drafts up to 38 feet may safely transit. By the end of 1967, the project for the current improvements is expected to permit drafts up to 39 feet and up to 40 feet at some time before 1969. By 1972, the Suez Canal Authority has announced that with the widening and deepening of the Canal, ships carrying a 48-foot to 50-foot draft and up to 135-foot beam will be permitted passage.
Oil traffic accounts for 73 per cent of the traffic through the Suez. Much of that will be lost if the project for improvement does not go forward, inasmuch as shippers have figured that it would be cheaper to round the Cape of Good Hope with super tankers unable to use the Canal rather than ship by the smaller vessels that can. The Canal Authority Chairman, Mashour Ahmed Mashour, has said that all but four of the 432 super tankers built up to 1966 will be accommodated by 1972.
The Panama Canal is not a sea-level canal. Through its system of heavy concrete locks— Gatun, Pedro Miguel, and Miraflores—a ship is raised 85 feet above sea level and then lowered to the sea level of the opposite ocean. Each lock is 1,000 feet long, 110 feet wide, and 41 feet over the sill. The Gatun .locks—there are three sets of twin locks—lift the ship bound from the Atlantic to the Pacific from sea level to Gatun Lake, which is 85 feet above sea level. The ship then steams about 20 miles to Pedro Miguel—one twin lock—and is lowered to Miraflores Lake which is 54 feet above sea level. On she goes to Miraflores Locks—two sets of twins—where she is lowered to the sea level of the Pacific. The Canal proper is 40 miles long. From deep water Atlantic to deep water Pacific, the ship has traveled 53 miles.
Without examining in detail tidal differences between the Atlantic and Pacific at a site that will be chosen for the new sea-level canal across Central America, it is interesting to note here that on the Atlantic end of the existing Panama Canal, the average mean tide is only two feet, with an extreme of three feet. On the Pacific end, 12.5 feet is the average mean with an extreme of 22.7 feet. The tidal period is very regular (twice daily) on the Pacific end but very irregular on the Atlantic end. The difference between the datum plane of the Atlantic and that of the Pacific is only 7.9 inches, the latter being the higher.
The tides are mentioned here as a suggestion that there could well be a problem of strong currents through a new sea-level canal at whatever site chosen for its construction across the Isthmus or some other part of Central America.
The controlling depth of the Panama Canal centers on the depth of the locks over their sills—41 feet. But this is not the only dimension that today prevents transit by a great number of ships of the world. Some of them have too great a beam or length, or both, that bars them from using the Canal. Thus, they are either restricted to certain runs where channel and other dimensions are suitable or else are faced with much longer voyages if they are to participate in wider maritime service.
Most of these larger ships—or “superships” as they are often referred to—are tankers, ore ships and other dry bulk carriers, passenger ships, and men of war. But these ships are not the disease that plagues the two great canals, they are but the symptoms. The disease is obsolescence. In the case of the Panama Canal, the obsolescence began to be felt as far back as the World War II years.
The effects of an inability to transit the Panama and/or the Suez Canal by the supership carriers in maritime commerce are not generally known in terms of the resulting lack of economies in freight rates. We do know that, as a generalization, the usages of the Panama Canal and the Suez Canal in the carriage of goods by water have netted the world, along with lower freight rates, a resultant lowering of prices of goods that come from overseas.
The average Panama Canal toll is $5,500. It would cost ten times that amount to send a vessel around South America. The charge is based on net registered tonnage—the net ton being 100 cubic feet of cargo-carrying space in the vessel. New York to San Francisco via the Panama Canal is 5,203 miles. Via the Straits of Magellan the distance is 13,125 miles. New York to Basra, Iraq, is 8,514 miles via the Suez Canal, and via the Cape of Good Hope is 12,012 miles. New Orleans to San Francisco via the Panama Canal is 4,678 miles, and via the Straits of Magellan, 13,541; Basra from New Orleans is 9,854 miles via the Suez Canal, and via the Cape of Good Hope is 12,540 miles. If the Panama Canal did not exist, the shortest route from New Orleans to Yokahama would be via the Suez Canal, or a distance of 14,398 miles instead of the present 9,115 miles.
It is interesting to look back 55 years to the 12th International Congress of Navigation that was held in Philadelphia in 1912—only two years before the completion of the Panama Canal—but five years after its construction was started. At that Philadelphia meeting the following resolution had been proposed for adoption:
1. It is desirable that a limit be set to the draughts of seagoing vessels.
2. Government aid should not be extended to the building of seagoing vessels whose draught exceeds 32.2 feet.
3. There should be an international agreement confining the maximum dimensions for seagoing vessels built or operated under government subvention; and these are tentatively suggested to be as follows:
Length 900 ft.
Breadth 105 ft.
Draught 32.2 ft.
4. Any maritime canal which has locks with a usable length of 1,000 feet, and a width of 110 feet and a 35-foot depth of water at the sill, will fulfill every reasonable requirement of navigation.
The resolution was not passed by that International Congress. No better example of an attempt to have the “tail wag the dog” can be offered. Whatever influence the resolution may have had on it, the depth dimension of the locks of the Panama Canal over the sill is 41 feet instead of 35 feet, but the other dimensions are the same as set forth in the resolution.
Eleven years later, another consequential meeting occurred. Commander John H. Walsh, Construction Corps, U. S. Navy (Retired), had an influential hand in the November 1923 meeting of the Society of Naval Architects and Marine Engineers in New York. Walsh, who was the general manager of the port of New Orleans at the time, drew attention to both the 1912 resolution and what, in his opinion was the resolution’s unsoundness. He pointed out the even-then-in- creasing dimensions of both ships and channels since the year 1912, though this growth was somewhat interrupted by World War I. He correctly said that these developments resulted from the demands of economy—the need for cheaper ways to carry ocean freight. That need still persists today.
With reference to men-of-war, he pointed out that larger vessels were needed in the interest of fighting efficiency.
Commander Walsh stated that at that time there existed in some quarters the feeling that the growth in ship size would be limited by the accommodation of the port and canal dimensions. His response to this was in part:
If each ship owner paid not only for the ship, but paid as well for his share of harbor and port improvements, the ports would feel sure the owners would not ask too much. But this is not the case. The government must deepen the channels; the port must enlarge its facilities. The cost of these improvements is paid only in small part by the shipowners.
Commander Walsh in this comment threw the spotlight on important responsibilities for providing and maintaining ports. They have not changed since then. The port exists for the benefit of the public, the trade, and its attendant economic effects—business and jobs, providing a high standard of living for the people whose port it is. Why then should not the responsibilities be kept on the shoulders of the public? Good port facilities make cargo-handling and delivery easier and faster, and this results in lower costs to the consumer.
And, since Commander Walsh spoke at that meeting, there have been few, if any, changes in responsibilities for the channels and the facilities. There is one thing in connection with channels that was not mentioned by Commander Walsh, that is: the channels to and through the port are deepened and maintained by the U. S. Army Corps of Engineers, as they have been for the past 90 years. In most ports, however, the deepening and maintenance extends only to certain limits from the faces of the wharves. For example, in New Orleans, the Army Engineers maintain the river channel, but only up to 100 feet from the faces of the wharves. The Port Authority has the responsibility for maintenance of depth within that 100-foot area. Since the importance of the port to the nation is becoming more and more recognized, it would seem that the Federal government might extend its responsibility for channel maintenance to include all the water up to the wharf face in all ports.
In considering such an extension of responsibility, the extremely important role of the port in national defense in time of war should be kept in mind. It is in the port where troops are embarked, and supplies, arms, and other equipment for their support are loaded into ships that move overseas. It is within the shelter of the port where imported strategic raw materials may still have to be unloaded in wartime.
Whenever channel and harbor depths, lock dimensions, or adequate wharf facilities prevent the entrance and use of the port by any ship of any class, be it tanker, bulk carrier, liner, or man-of-war, an era of retrogression has begun, whether the ship already exists, or is under construction or planned.
Assuming that the new canal across Central America has been built and the Suez Canal improvements will have been completed by a definite future date with dimensions that permit passage of the largest ships in the world, isn’t it a fair question to ask whether the channels of the ports of our country will have been enlarged proportionately by that date?
Following is a list of the channel depths of some of our major port project depths (i.e., the dredged depth provided by legislation) and the controlling depths. Also listed is the tide that can be depended upon for navigational purposes. It is notable that the project depth for a port does not in all cases seem to have included consideration of the normal tide. For example, the project depths for Boston and New Orleans are both 40 feet. Yet, the mean tide level at Boston is almost five feet, and at the mouth of the Mississippi River at Southwest Pass, it is 0.6 feet. None of the U. S. ports on the Gulf of Mexico are favored with a normal tidal range. Winds are the major influence.
In September 1964, there were 1,471 commercial ships on order with a deadweight tonnage of 2,000 and over throughout the world. Since that year, there have been ships with even greater dimensions constructed and put in service, placed under construction, or planned.
For example, the tanker Idemitsu Maru, launched in Japan in 1966, is rated at 205,000 deadweight tons. She is 1,177.5 feet long, with a beam of 161.85 feet and her full load draft is 56 feet. More recently, in September 1966, two Japanese shipyards announced that they were awarded contracts worth $120 million by an American company for six 276,000- ton super tankers. The ships will be the largest vessels ever built. The contract from the National Bulk Carriers, Inc., is the largest ship export contract ever obtained by Japan. Mitsubishi Heavy Industries, Ltd., and Ishikawajima-Harima Heavy Industries, Ltd., said the contracts were signed in New York on 15 September 1966.
The shipyards said that the first two tankers would be delivered by the fall of 1968, the second pair by the spring of 1969, and the last two by the summer of 1969. The ships as reported will be 1,130 feet long, 175 feet wide, and 72 feet in draft.
Of course, there will be only a few ports in the world that can accommodate these vessels at full draft. They are mentioned here purposely to indicate the trend.
Of the 1,471 ships on order in September 1964 with a deadweight tonnage of 2,000 or more, 428 have a full load draft of 31.5 feet or more. When broken down by dimensions and classes, the list indicates the following:
|
Draft |
31.5 to 36 |
37 to 40 |
41 to 45 |
46 to 50 |
51 to 55 |
|
Tankers |
14 |
124 |
65 |
39 |
4 |
|
Bulk |
97 |
33 |
1 |
3 |
|
|
Other |
25 |
19 |
4 |
|
|
|
Total |
136 |
176 |
70 |
42 |
4 |
A ship with a full load draft of 31.5 feet at 10 knots needs a channel of 38 feet or more if she is to have about two feet of clearance under her keel. The normal trim, the squat caused by speed and bottom effect, and draft increase due to fresh water add up to about seven feet.
Of the 1,471 ships, there are 480 having a beam of 75 feet or more. A ship with a 7 5-foot beam can barely get through the Welland Canal Locks, which are 80 feet wide—and incidentally only 30 feet over the sill—and cannot get through the 75-foot wide lock between the Mississippi River and the newly constructed Mississippi River Gulf Outlet, a $105 million project.
A listing of the 480 ships according to their beam dimensions appears below:
So, with the many ships existing today that cannot use either the Panama Canal or Suez Canal, as well as those building or planned, the need for a new canal across Central America and the need for increasing the dimensions of the Suez are daily becoming more pressing.
When they have become realities, will the dimensions of channels serving the ports of the United States—at least the major ones— be ready to accommodate all of the ships that can pass through those Canals at full load draft? This is a most logical question in view of the fact that even now not all of the major ports of the United States can receive all the so-called super ships that have been built to economize on the cost of ocean hauling.
Doubtless, all of the major ports of the United States are now trying to predict the shape—and, just as important, the size—of ships to come. One such study attempted to forecast the dimensions and the tonnage of cargo ships, tankers, and bulk carriers over the next 70 years. The study predicted a small but steady increase in tonnage of general cargo ships and a much greater increase in the size of bulk carriers. But, as might be expected, tankers are expected to double in tonnage (see opposite column) during that same period.
The conclusions show that the U. S. government and that of the United Arab Republic recognize the need and are taking steps to meet the requirements of the fast expanding dimensions of ships. But the question also arises and it is one which stands repeating: Will the dimensions of the ports of our nation be increased in time and will they be ready to handle all the ships that can pass through those greater man-made waterways?