VI. THE GREAT LAKES 



The Great Lakes are included within the scope 

 of this report under the provisions of the Marine 

 Resources and Development Act of 1966. 



Within the boundary of the States of the 

 United States and the provinces of Canada which 

 adjoin the Great Lakes is an area with a population 

 of 55 milhon. It is the source of almost 80 per 

 cent of the steel, 40 per cent of the agricultural 

 produce, and the greater part of the equipment 

 and products of heavy industry made in the 

 United States and Canada. Much of the growth 

 and potential of this region is based on the vast 

 Great Lakes waterways which, until 1959, had no 

 link to the ocean for the passage of deep-draft 

 vessels. 



When the St. Lawrence Seaway was officially 

 opened on June 26, 1959, making the Great Lakes 

 accessible to such vessels, a fourth U.S. seacoast 

 was created that added even more potential to the 

 heartland area of this country and also of Canada. 



The Lakes contain the largest mass of fresh 

 water on the earth's surface, and represent approx- 

 imately 40 per cent of the surface waters of the 

 continental United States. Furthermore, their 

 combined area of 95,170 square miles is about the 

 same as that for each of the following seas: Persian 

 Gulf, English Channel, Gulf of California, and the 



Irish Sea. Because of their size, they frequently are 

 referred to as inland seas, laboratory sized oceans, 

 and the mid-continental coastal area. 



The maximum lengths of the Lakes range from 

 350 miles (Superior) to 193 miles (Ontario); 

 maximum breadths range from 183 miles (Huron) 

 to 53 miles (Ontario); maximum depths range 

 from 1,333 feet (Superior) to 210 feet (Erie); and 

 the mean depths range from 487 feet (Superior) to 

 58 feet (Erie). 



The Great Lakes are subject to essentially the 

 same physical, chemical, biological, meteoro- 

 logical, and geological regimes as the oceans, but, 

 in addition, possess definite boundaries and each 

 generally has a single weather system over it at a 

 given time. Furthermore, the Great Lakes drainage 

 basin is a discrete physiographic unit, within which 

 exist integrated social, political and economic 

 regimes directly dependent upon the Lakes. 



VII. SOCIOECONOMIC TRENDS 



Seventy-five per cent of our population now 

 lives in States bordering the ocean and the Great 

 Lakes. This population is growing at a faster rate 

 than the total U.S. population. There is developing 

 a nearly continuous urban concentration along the 

 Atlantic Ocean from Boston to Norfolk. The same 

 phenomenon is appearing along the California 



Figure 4. The Great Lakes- America's fourth seacoast. 



Ill- 10 



