The Mackinac Bridge
By David J. Olson
The story of the Mackinac Bridge is more than just cars and concrete or men and
machines. It is a tale with heroes and villains filled with suspense, drama, and
disappointment. It is also a magnificent achievement. With its official opening on
November 1, 1957, by Governor G. Mennen Williams, one era was ended and another begun. As
one prosaic representative noted, "The North and South of the state have long been
engaged; they now have a wedding ring!"
This marriage was long awaited. For, though scenic, the water which geographically
separates the Upper and Lower Peninsulas has also caused economic, political, and cultural
divisions as well. Thus, because of necessity, interest soon developed for bridging the
Straits. As early as 1884, proponents of construction like the editor of the Grand
Traverse Herald plumped for such a structure. Even so noteworthy a person as Commodore
Cornelius Vanderbilt called for action. Standing before a board of directors meeting at
the Grand Hotel, he summed up his feelings, declaring that "what we need is a bridge
across the Straits."
Though needed, the bridge was not built in the nineteenth century. Still, interest was
not extinguished. It lingered, waiting to be rekindled. And, rekindled it was. Buoyed by
automobile production in the 1920s, advocates again pushed for a Straits bridge. It was
foolish, they argued, that such modern means of transportation like the automobile
depended on outdated ferry service.
Several ideas were put forward. One, promoted by Horatio "Good Roads" Earle,
Michigan's first state highway commissioner, called for a floating tunnel. Another, urged
by Charles Evan Fowler, called for a series of causeways and bridges beginning at a point
near Cheboygan, across to Bois Blanc Island to Round Island, over the west tip of Mackinac
Island, and then across the channel to St. Ignace.
Highly imaginative and somewhat far-fetched, ideas like these were based on the
prevailing assumption that the direct course from Mackinaw City to St. Ignace was unsuited
for bridge construction. The direct route, as engineers and skeptics alike believed, was
impossible to build a bridge over. Current theory maintained that the area rock could not
support the structure's weight, and even if it could, the elements would destroy anything
that could be erected.
In the face of these arguments, proponents of a bridge stood defenseless. Though the
State Highway Department funded and published a report in 1928 stating that a bridge
directly across the Straits would cost $30,000,000, no further action was taken.
Thus the 1920s faded into the 1930s with little progress toward a Straits bridge. The
passing of time brought with it renewed hope, however. For in the 1930s the Great
Depression occurred, and with it came the possibility of federal public works funds.
Enamored with the possibility of federal aid, the Michigan Legislature created a Mackinac
Straits Bridge Authority in 1934. Organized to investigate the possibility of building a
bridge, to issue bonds, to build a bridge, and to operate it, they presented two plans to
federal authorities. Both failed. The first plan, a revision of the Fowler island hopping
scheme, was presented to the Public Works Administration in 1935. It was rejected. The
second, covering a direct route, was sent to the Works Progress Administration in
September of 1936. It, too, was rejected.
Disappointed but undaunted, the Bridge Authority pushed forward. They contracted with
the long-span bridge engineering firm of Modjeski and Masters in 1937. This contract
called for the Authority to furnish relevant data for a route from Mackinaw City to St.
Ignace, and for the engineering firm to provide a construction report based on that
information. Once soundings and borings were taken, traffic data were obtained, and
geological studies were done, the information was turned over to Modjeski and Masters.
The report which resulted from this study did not disappoint bridge advocates. Instead,
it judged that construction was possible, probably at a cost of around $24,340,000. In
addition, it also called for the building of a causeway from St. Ignace 4,200 feet south
into shallow water.
To help implement the plan, the Highway Department, acting for the Bridge Authority,
contracted for a causeway, which was completed in 1941. With this done, it seemed as if
the bridge might be built. But, just when construction seemed possible, World War 11 broke
out, putting an end to work. Worse yet, with enthusiasm fading, the Legislature abolished
the Bridge Authority in 1947. Soon afterward funds were appropriated to construct an
ice-breaker ferry capable of carrying 150 vehicles. It was expected that this measure
would take care of the foreseeable demand for Straits crossing service.
Though all seemed lost, proponents of a Straits of Mackinac Bridge did not give up.
Instead they formed an InterPeninsula Communication Council to drum up public opinion in
support of the bridge and to resurrect the Bridge Authority. Eventually they were
successful, for in 1950, the Authority was re-formed with former United States Senator
Prentiss M. Brown at its head.
Born and raised in St. Ignace, Prentiss M. Brown had long recognized the political,
cultural, and economic difficulties spawned by the inadequate transportation across the
Straits. He had fought for the bridge during his Washington tenure, personally appealing
to President Franklin D. Roosevelt. So when the opportunity presented itself, Brown was
the natural choice to be chairman of the newly reconstituted Bridge Authority in 1950. It
proved to be a wise choice.
In the beginning, the mandate given the Mackinac Bridge Authority was thin. Possessed
with only the power to study the feasibility of construction, they had no authority to
finance or construct. Despite these limitations, the Bridge Authority remained undaunted.
To answer the age old question of whether a bridge could withstand the area's natural
elements they called upon three leading experts on wide-span bridges. By January of 1951,
the experts had delivered a report which said that not only could a bridge be built but
that it could be placed along the direct north/south route, utilizing the 1941 causeway.
Armed with these favorable reports, the Bridge Authority returned to the legislature
asking for the power to finance and construct a bridge across the Straits. Though
convinced of their proposal's value, the Authority did not win quick approval. The
legislative battle lasted for several months during early 1952, with antagonists lining up
on either side of the issue. Those who opposed the bridge cited several reasons. For one,
they maintained, this structure was too costly and could not possibly be justified for
such a sparsely populated area. For another, they mentioned reputable engineers who
doubted that a bridge could be built.
Of course, proponents of the Straits of Mackinac Bridge argued their case too. The idea
that such a structure could not be built was bunk, they declared. After all, had not all
current studies pointed to the fact that neither existing rock nor climate conditions
would hinder the project. Furthermore, the bridge would be a shot in the arm for the Upper
Peninsula, ending traffic tie-ups and bringing more tourists and hunters providing for an
economic resurgence.
Eventually bridge proponents prevailed. With one more than a two-thirds majority,
Public Act 214 sped through the legislature. Signed into law by the Governor on April 30,
1952, this Act had immediate effect, authorizing the Mackinac Bridge Authority to bond,
build and operate a toll bridge.
If getting legislative approval was difficult, securing funds to build the Mackinac
Bridge was even worse. Because of constitutional and legislative restrictions, the Bridge
Authority had to sell the bonds on the open market. This proved painful because the bond
market was generally poor during 1953 and 1954. So bad was the market that bond sales had
to be postponed twice.
On the third try, the Bridge Authority was successful but barely. In a revised plan,
introduced in December of 1953, bonds were sold in two series. One, the so-called first
lien bonds, would be issued in the amount of $79,800,000 with a four percent interest
rate. Another, called second lien bonds, was to have an interest rate of five percent. As
required by law, these offers had to be subject not only to public sale but to approval of
the State Administrative Board. It was there in mid-December that trouble began--a
difficulty so ill-timed that the project almost failed.
At the meeting with the Administrative Board and the Bridge Authority on December 15,
1953, one Board member opposed the financing methods. He maintained that the financing was
too expensive and that the whole question should be brought before the voters.
Fortunately, before a vote could be taken, this meeting was postponed.
Yet the postponement of this meeting did end the trouble. On December 16, Senator
Haskell Nichols of Jackson filed a petition with the State Supreme Court asking it to
prevent the Administrative Board from approving the sale. Before any action could be
taken, members of the Bridge Authority saw court officials, asking them not to block the
bonds. The argument was that a complete court hearing could be held between December 17,
1953 (the date of sale of the bonds) and February 17, 1954 (the date of the delivery of
the bonds). This was done. Subsequently on January 22, 1954, the court upheld the right to
sell the bonds.
Thus, with the legal impediments removed, bids for Mackinac Bridge Authority bonds were
accepted on December 17, 1953, in the office of Governor G. Mennen Williams. Immediately
after this meeting, the Bridge Authority approved the sale. And, not long after, the State
Administrative Board convened and voiced their approval too.
At long last, the hoped for bridge could be built. Following ceremonial groundbreaking
which took place on May 7 and May 8, respectively at St. Ignace and Mackinaw City, work
began.
The first construction challenge awaiting them was to establish precise locations for
each of the thirty-four bridge support foundations. This was done by establishing eight
land and six sea-based surveying stations. From these positions, the surveyor utilized
triangulation techniques to plot the exact position for each bridge section.
While this work was being done, the largest armada in the history of marine
construction equipment was assembled at the Straits in 1954. Others had begun assembling
caissons and superstructures as far off as Indiana, Pennsylvania and Ohio.
The actual building of the bridge was exacting and challenging. One of the most serious
challenges went to the builders of the foundations--Merritt-Chapman & Scott
Corporation. Piers 17 and 22, the huge anchorages for the cables, and piers 19 and 20, the
support for the 46-story towers, were difficult. For the tower piers, huge caissons were
filled gradually with rock and cement and lowered carefully to bedrock with precise
calculation. Between the anchorage piers and the cable tower piers with two cables went
piers 18 and 2 1. These two required huge foundations.
Though work was painstaking, it proceeded well, and the foundations were finished in
1955. Then, structural steel was put into place by the American Bridge Division of United
States Steel Corporation. On July 2, 1955, the first piece was put in. Slowly the shape of
the giant towers appeared across the Straits as creeper cranes pulled up each section and
then moved within themselves. Riveters followed, making the work permanent.
The next phase, putting the support cable in, required the placing of a catwalk across
the span. For, unlike other structural parts, the cable had to be assembled on-site. Quite
literally, it had to be "spun" one strand at a time, since its 12,500 ton weight
could not be lifted.
Looking back on the project, Dr. David B. Steinman, designer of the Mackinac Bridge,
viewed it as the crowning achievement of his career. It was to him both a remarkable
engineering feat and a work of art. Indeed, he was careful to make sure to preserve the
grace and setting of the structure. He insisted that the 552 foot towers be painted ivory
and that the span itself be green, so that its natural lines would be as graceful as a
harp.
What, beyond beauty, has the bridge accomplished? For one, it has proven its critics
wrong. Not only has it been an engineering success, but its ever increasing traffic has
provided a growing business traffic for the Upper Peninsula. It has reduced the crossing
time, including waiting time, from an average of one-and-a-half hours in winter or
two-and-a-half hours in summer, to just ten minutes. Because of its capacity of 6,000 cars
per hour (compared with the 462 cars per hour capacity of the state ferry service), the
bridge has eliminated lines of cars which had stretched as long as seventeen miles on U.S.
27 and seven miles on U.S. 131, which could produce a waiting period of up to 19 hours.
Most important of all, the bridge has joined the Upper Peninsula and Lower Peninsula,
eliminating a geographical barrier, and has proved the wisdom of those who guided it
through its financing, designing, and building.
Interesting Facts
|
Length of Main Span
|
3,800 Ft.
|
|
Length of Suspension Bridge (Including Anchorages)
|
8,614 Ft.
|
|
Total Length of Steel Superstructure
|
17,918 Ft.
|
|
Length of North Approach (Including Mole)
|
7,791 Ft.
|
|
Length of South Approach
|
735 Ft.
|
|
Total Length of Bridge and Approaches
|
26,444 Ft.
|
|
Height of Main Towers Above Water
|
552 Ft.
|
|
Depth of Tower Piers Below Water
|
206 Ft.
|
|
Number of Main Cables
|
2
|
|
Diameter of Main Cables
|
24.5
Inches
|
|
Number of Wires in Each Cable
|
12,580
|
|
Diameter of each Wire
|
0.196 Inches
|
|
Total Length of Cable Wire
|
41,000 Miles
|
|
Weight of Cable, Wire and Fittings
|
12,500 Tons
|
|
Total Estimated Weight of Superstructure
|
66,500 Tons
|
Selected Bibliography
- Brown, Prentiss M. The Mackinac Bridge Story. Detroit, MI: Wayne State University
Press, 1956.
- "Mackinac Bridge" in Civil Engineering, May 1956.
- Ratigan, William. The Long Crossing. Grand Rapids, MI: William B. Eerdmans, 1959.
- Ratigan, WIlliam. Straits of Mackinac. Grand Rapids, MI: William B. Eerdmans,
1957.
- Rubin, Lawrence A. Mighty Mac; The Official Picture History of the Mackinac Bridge.
Detroit, MI: Wayne State University Press, 1958.
- Steinman, David B. Miracle Bridge at Mackinac. Grand Rapids, MI: William B.
Eerdmans, 1957.
The Michigan Department of State first published "The Mackinac
Bridge" as a Great Lakes Informant (Series 2, Number 2). © 1998 Michigan Historical Center.
For more information and pictures of the Mackinac Bridge, visit:
Michigan Historical Center, Department of History, Arts and Libraries
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