The Great Lakes… 84% of the continent’s fresh water… a different story in every drop.
By E.B. Williams
The dramatic part of our story began about a million years ago — geologically, a rather recent period. Many hundreds of millions of years before, events took place which set the stage for the great drama, the like of which has occurred nowhere else in the world. The original North American continent was a mass of igneous rock which lay to the north of the Great Lakes region. Forces beneath the surface caused a series of uplifts and downward foldings, and the seas receded, only to come again. Even mountain ranges were formed, worn down and then thrown up again, over the eons of time. The Great Lakes area was a sort of submerged basin or bowl which gradually became lined with layers of materials, some hard and some soft, but finally, when the whole region was above sea level, a great river system existed. Then came the epoch known as the Pleistocene, the age of great glaciers, and our story begins.
A gradual climatic change of longer winters, in which the snows of one year overlapped those of the next, caused the formation of two glaciers, one to the west and one to the east of Hudson Bay, known as the Keewatin and the Labrador glaciers. As they grew, larger and deeper, over hundreds of years, these glaciers spread out and gradually merged together. They were pushed outward by their own weight and reached a thickness estimated to have been as much as six miles in places. Consider a jet plane, leaving a vapor trail 30,000 feet high and then imagine a mass of ice that thick — twice the height of our highest mountains. Great masses of rock were sheared off the hills and mountains and shoved along the path, gouging out whole regions where the surface rock was softer, and spreading the debris to the south, all the way to the Ohio River, into the Adirondacks and westward beyond the Mississippi, as far south as the northeast corner of Kansas and the upper third of Missouri.
At times it melted faster than it advanced, and receded, only to come again. There were four great advances, but the last one, known as the Wisconsin glaciation, was the most important to the Great Lakes area. It did not extend quite as far south as previous ice movements had done and, like the others, came and went in pulsating movements, each leaving its mark in morainic drift, thus telling the story of its life. This last glacier came in lobes, which left ridges roughly following the contours of the Lakes themselves. Strangely enough, however, one section in central Wisconsin was left unglaciated and the famous Dells of the Wisconsin River developed. As time went on, these lobes became more like individual glaciers and occupied the basins of the Great Lakes.
As these glacial lobes retreated northward, tremendous quantities of run-off water drained into the Mississippi valley. But in time, the lobes reached the drainage divide where the land sloped toward the ice front. At such places, large crescent-shaped lakes would form. The first of these, at the western end of Lake Erie, has been called Lake Maumee. It covered the northwest corner of Ohio and reached down to Fort Wayne, Indiana, where it drained into the Wabash River. The Wabash, of course, was much larger than it is today and later, when the Maumee River itself became established, it flowed in the opposite direction. Thus was born the first of the Great Lakes, the ancestor of Lake Erie. Its level was 230 feet higher than the present level of the Lake.
Lake Maumee grew to a much greater size, while similar lakes formed at the ends of other glacier lobes, Green Bay, Saginaw Bay and Lake Michigan, all draining down the Mississippi. There were several stages of the Erie basin and their beaches can be seen today in the vicinity of Cleveland. Most clearly defined are the beaches along Detroit Road and Center Ridge Road. Another lobe of interest formed in the vicinity of the Finger Lakes in New York State, which drained down the Susquehanna River into Chesapeake Bay. At this time, however, Lakes Superior, Huron, most of Michigan and Ontario were still under the glacier.
Gradually, through many centuries, the Labrador Glacier withdrew, leaving the end of Lake Superior, which drained down the St. Croix River to the Mississippi. In the east, a long, crescent-shaped lake developed at the upper end of Lake Ontario and drained down the Mohawk. Then, in time, all the Great Lakes merged together and the principal outlets were the Mohawk, Lake Champlain and the Hudson River, which was also an estuary of the Atlantic Ocean. Lake Erie, at this time, had ceased to be fed by the glacier, or by the northern lakes through Lake St. Clair, which was then just a swampy area. Consequently, the surface of Lake Erie dropped to its lowest level, some twenty or thirty feet below the present level.
During all this formative period in Great Lakes history, another great change was taking place — slowly at first, and then with more speed. As the tremendous load of ice melted, ran off and receded to the north, the earth’s surface rose. This fact is revealed by old beaches, once level, but now sloping. In fact, this rise was near a “hinge line,” extending in a northwesterly direction from Ashtabula, across Lake St. Clair to Grand Rapids and then more westerly across Lake Michigan. As a result, the old outlets into Lake Erie and the Illinois River were reestablished, but Georgian Bay had an outlet into Lake Ontario and from that Lake into the Mohawk. The St. Lawrence River, however, did not then exist, but a lobe of the Labrador Glacier drained down the Hudson.
Finally, when the glacier had receded beyond the lakes region and the Great Lakes were drawn down almost to their present levels, the three Upper Lakes drained principally from Georgian Bay to Lake Nipissing, down the Ottawa to the St. Lawrence. The St. Clair River again was just a trickle and the surface of Lake Erie was lowered. Then, as the lands to the north lifted still further, the outlets changed once more and established the system which exists today. Lakes Superior and Huron became independent, the higher waters of Lake Superior being held back by the rim of the old Cambrian sandstone ledge at that point.
At this time, I would like to back up a few million years — just how many is not important — when the rock formations in the Great Lakes basin were being established. As I mentioned before, this basin became lined with layers of rock, the oldest of which is known as Cambrian. Above the Cambrian came the Ordovician, which was mud deposited from an ancient sea, and becoming a soft shale. Then came Silurian time, when climates were mild and marine life was abundant.
Great quantities of shellfish skeletons lined the bottom and gradually a hard limestone was formed. This Silurian limestone is also called Niagaran, which is exposed in the vicinity of the Niagara River. This rampart extends in a northwesterly direction, across Ontario, in a broad arch separating Georgian Bay from Lake Huron. It forms the southern shore of the upper peninsula of Michigan and then circles southward between Green Bay and Lake Michigan and down the Wisconsin shoreline.
When the ice of the Ontario lobe of the Labrador Glacier withdrew far enough north so that the “melt waters” fell below the level of the Niagaran escarpment, the overflow from Lake Erie fell over the rocky ledge near Lewiston, New York, and Niagara Falls was born. Gradually the softer shale below the limestone washed away and the overhanging limestone broke in chunks, falling to the lower level and forming a gorge. Upstream, the gorge becomes narrower when the water supply was reduced because of the first separation of Lake Erie from Lake Huron; but with the tilting of the land mass, a greater flow resumed and the gorge widened, as the Falls worked upstream to the location of the present whirlpool.
During an earlier period, before the last ice invasion, a river flowing in a northwesterly direction poured over the Niagaran escarpment near the town of St. David, and cut a gorge as the Falls worked upstream. The glacier then passed over and completely filled this gorge with rock debris, which then became compressed and cemented together, but not as hard as the surrounding rock. This condition resulted in a great whirlpool, as the Falls itself continued to work its way upstream to the present location.
Great Lakes Today
In summary, this brief, thumbnail sketch of the Ice Age in North America began about a million years ago. The glaciers reached their southernmost limits about half a million years ago. The Wisconsin glaciation occurred about 200,000 years ago and, in its final retreat, some 35,000 years ago, the Great Lakes began to be established. Niagara Falls was born about 20,000 years ago and the Lakes, as we know them today, are roughly only 3,000 years old.
In addition to the Great Lakes themselves, nature, a billion years before, created the iron ores of the Lake Superior region. Any living organisms existing at that time were of a very low order, so we cannot claim that it was intended for us! However, it is there, but somewhat more difficult to mine than it was seventy-five years ago. For the making of steel, we also have coal and limestone in great abundance. Man can be proud of his creative genius in learning how to use these raw materials, but after all, how puny are the working of man, as compared to the workings of God!
Let us move now to more recent times. Jacques Cartier was the first white man to sail up the tremendous and seemingly endless river he had entered on St. Lawrence’s Day in 1535, only forty-three years after Columbus had discovered America. He finally reached an impassable barrier, the Lachine Rapids, and there he stopped. Eighty years later Samuel de Champlain reached Georgian Bay, then Jean Nicolet explored the Straits of Mackinac and beyond. Meanwhile, the Iroquois Indians, along the southern shores of Lake Erie, prevented travel from that direction and Lake Erie was yet to be discovered and seen by the white man.
Father Hennepin was the first to see Niagara Falls; this was late in 1678. Hennepin was one of LaSalle’s aides. LaSalle had spent ten years preparing for his shipbuilding venture and voyage up the Great Lakes from Lake Erie. The story of LaSalle and his Griffin is well-known. The tiny vessel, only 60 feet long, set sail on August 7, 1679, to cross Lake Erie and the unknown waters beyond.
Let us skip over the next 283 years, which brings us up to the present moment. The Great Lakes are still here, as beautiful as ever, all 95,000 square miles of them, and in recent years we have conquered the St. Lawrence River and we have the long-sought access to the sea. Ships of all the world can now reach our shores. But what of the future? In particular, what does the future hold for our Great Lakes fleet of ore carriers? We have reached an economic crossroad. Foreign competition is making a strong bid for a share in the supply of this raw material.
At one time there were over 500 ships in the Great Lakes fleet. Ten years ago there were 300 in the ore trade alone. Today that figure has shrunk to 200 and many of those will probably see little service in the future. During the past decade, while the number of vessels was diminishing, the annual carrying capacity remained fairly constant, because our newer ships are also much larger than the old-timers. In a very few years, however, even our existing fleet will be cut in half and our annual carrying capacity will be down to about 55 million long tons. At that time, however, say in 1966, if our industrialists continue to display the aggressive intelligence with which they have been endowed, our Great Lakes fleet will begin to regain its rightful prominent position in the movement of iron ore and will again become the envy of the world. The revolutionary changes in the Lake Superior mining areas and the equally basic changes in the making of iron and steel, present a challenge to all who are responsible for transporting the raw material to the blast furnaces.
Our maximum size ships today can carry 25,000 tons and their operating season is restricted to about seven months. Foreign ships, with foreign crews, are competing in this business, with deliveries right here in Cleveland. Other foreign ships, of twice the above capacity, can deliver foreign ores to our east coast ports at rates sufficiently low to overcome the long rail haul to Pittsburgh.
How can we cope with such formidable competition? Subsidies might help but this would be temporary relief only. A faster tax write-off would help and this is fully justified. A more realistic tax climate in the mining areas would help and this is also justified. High iron content pellets from the Lake Superior ranges are in great demand and pellet production is increasing. To turn the trick, however, we must have larger ships and a longer operating season.
Soo Locks today (photo from 1992)
Our Government has now started construction of the new lock at the Soo. It will be at least 1,000 feet long and 100 feet wide. Our current dredging program has provided minimum channel depths of 27 feet, so that the larger ships may draw 25 feet 6 inches at low water datum. This is the opportunity for our naval architects and vessel operators of this generation to come through with bold new thinking. What will be the nature of our new fleet?
I believe there will be a group of maximum size ore carriers capable of carrying 35 to 40,000 gross tons of ore and I believe that such ships, and others for that matter, will be operated for fully nine months in an average season. Such vessels could each carry up to two million tons in a year.
Time does not permit discussing the details of these “dream” boats but I will say that many designs are on the drawing boards today. The trend, I believe, will be toward self-unloaders, but whatever their technical characteristics may be, we must have an integrated transportation system. New building berths are necessary, new dry docks, new loading facilities and new unloading terminals. Any enterprise of this magnitude must be supported by industry groups, just as many of the new mining developments are joint efforts.
The extended operating season demands no new or unknown techniques. We know that it can be done; it is just a matter of doing. The pellets can be handled on conveyor belts, winter and summer. Air bubbling systems can keep the harbors open, Deicing equipment will be necessary on the ships, at the locks and at the terminals.
Much more could be said about the geological history of the Great Lakes but I will leave it to your more leisurely moments to read or reread this fascinating story. Much more could be said about the future of our Great Lakes ore carriers but I have already taken too much time.
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About the Author: Mr. E. B. Williams, a Trustee of the Great Lakes Historical Society, is also Naval Architect of the Society’s Museum at Vermilion, Ohio. Retiring earlier this year as Vice-President, Sales, of The American Ship Building Company, at Cleveland, he is now Consultant for the Company.
This paper was presented at the Annual Meeting of the Great Lakes Historical Society, June 13, 1962.
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