ments remained relatively stable during that period 

 (See Figure 3). Foreign commerce accounted for 

 56 per cent of the total volume in 1965. 



During 1950 to 1965, the bulk commodities of 

 crude petroleum and petroleum products, ores, 

 coal, and grain dominated the commercial deep 

 draft tonnage. As shown in Figure 4, these 

 commodities accounted for approximately 74 per 

 cent of the total volume of commerce handled in 

 coastal and Great Lakes harbors in 1965. 



Preliminary forecasts indicate that total foreign 

 oceanborne commerce passing through U.S. ports 

 will increase from about 350 million tons in 1965 

 to over 1 ,250 million tons in the year 2000 (See 

 Table 3). The forecasts show an increase of 73 per 

 cent in demand for waterborne transportation in 

 the liner trade;' irregular trade' ° will increase 371 



Liner trade refers to liner (berth) service which is 

 defined as a scheduled operation by a common carrier 

 whose ships operate on a predetermined and fixed 

 itinerary over a given route, at relatively regular intervals, 

 and are advertised considerably before sailing in order to 

 solicit cargo from the pubUc. 



Irregular trade (service) is comprised of "tramp" and 

 other types of service which do not conform to the 

 criteria described for a common carrier in "liner" service. 

 A "tramp" ship in traditional terms is one that operates 

 on an irregular or unscheduled basis from one port of 

 lading to one port of discharge. Irregular trade would 

 generally include dry buUc shipments of ore, grain, coal, 

 etc. 



per cent; and tanker trade will increase 184 per 

 cent. Projections of foreign commerce on the 

 Great Lakes, or domestic deep draft shipments, are 

 not available at this time. 



IV. TRENDS IN VESSEL SIZE AND IMPLICA- 

 TIONS 



While analyses of future commodity volumes 

 require much more intensive treatment, continuing 

 technologies point assuredly to changing means 

 being employed for handUng present as well as 

 future volumes of commerce. Changing vessel 

 technology alone will necessitate considerable in- 

 vestment in harbor and port development or 

 redevelopment. 



A. Petroleum Vessels 



Growth in the cargo-carrying capacity of deep 

 draft vessels has been steadily on the rise since 

 World War 11, and has shown an exceptionally 

 significant increase during the past decade. In 

 1945, the standard size petroleum vessel was the 

 16,460 dead weight ton (dwt)' ' "T-2" tanker. In 



Dead weight ton identifies a ship's total carrying 

 capacity including internal provisions, at salt water, 

 summer load hne immersion. Actual cargo capacity is 

 slightly less. For example, a 50,000 dwt tanker can carry 

 about 47,000 tons of crude petroleum. 



IN MILLIONS OF SHORT TON! 



600 



500 



400 



200 



800 



L 



FOREIGN IMPORTS 

 AND EXPORTS 



DOMESTIC 



1950 51 52 53 54 55 56 57 58 59 1960 61 62 63 64 65 



CALENDAR YEAR 



Figure 3. Total oceanborne and Great Lakes foreign and domestic commerce. (Source: U.S. 

 Army Corps of Engineers) 



III-65 



333-093 O - 69 - 15 



