Figure 5. The modem supertanker dwarfs the conventional tanker of World War 11. 

 (Courtesy of the Reader's Digest Association (c) 1968) 



increases, resulting in marked savings in delivered 

 unit costs. 



B. Containers 



Paralleling the growing size of vessels, in terms 

 of transport cost reductions, is on-going, radical 

 change in handling non-bulk cargoes— the move to 

 containerization. The use of standard sized van 

 containers (8 feet wide, 8 feet high, and 10, 20, 

 30, or 40 feet long), which are enclosed, perma- 

 nent, reusable, and weather tight, promises to 

 virtually revolutionize ocean transportation opera- 

 tions. 



The containers can be loaded with goods at a 

 factory far inland and then transferred to truck, 

 train or ship without being unsealed until they 

 reach the customer. The sealed boxes travel 

 routinely from inland producers on one side of the 

 Atlantic, for example, to inland consumers on the 

 other. 



The shipping industry is investing substantial 

 sums in constructing new ships specially designed 

 to handle containers and refitting older ships for 

 the same purpose. Major benefits of the containeri- 

 zation process have been identified as: reduced 

 handUng and pilferage; reduced damage to cargoes; 

 faster delivery, with ships in port only hours 

 instead of days; and significantly reduced in- 

 surance rates. Presently, about 4 per cent of 

 general cargo tonnage is moving in containers. It 

 has been estimated that at least 70 per cent of the 

 tonnage could be containerized.* ' 



VI. IMPLICATIONS 

 TERMINALS 



FOR HARBORS AND 



The trends in ship size and cargo handling 

 technology impose new requirements; one set 

 relates to required depths for harbors and chan- 

 nels, another to requisite on-shore supporting or 

 service facilities. 



A. Harbor and Channel Dimensions 



During the 1940's, the T-2 tanker (16,460 dwt) 

 was used as a yardstick in determining that a depth 

 of 35 feet was required at major U.S. ports. But 

 tankers of 35,000 dwt required 40 foot depths and 

 necessitated further enlargement of harbors and 

 channels. The largest tanker in service today needs 

 at least 70 feet. Figure 6 shows dwt-draft relation- 

 ships. 



Figure 6. Relationship between tanker tonnage 

 and draft. (Source: U.S. Maritime Administration) 



At present, only 10 per cent of the world's 

 major ports have controlled channel depths in 

 excess of 47 feet;'* only three U.S. harbors 



R. P. Holubowicz, Transmodalism, United States 

 Naval Institute Proceedings, February 1968. 



U.S. Maritime Administration, Merchant Ships of 

 100,000 Tons Deadweight and Over, April 1967. 



III-68 



