By Dr. Frank Griggs, Dist. M. ASCE
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Proposals to span the Mississippi River by a bridge were submitted by Charles Ellet, Jr. in 1840 for a 1,200-foot suspension bridge and by John A. Roebling in 1868 for another suspension Bridge. A local engineer by the name of Truman Homer proposed a tubular bridge similar to Stephenson’s Menai Straits Bridge in 1865 with three 500-foot spans. With the opening of several bridges upstream on the Mississippi, the City of St. Louis feared losing its claim as the gateway to the west and started to plan its own bridge. This would require a charter from both Missouri and Illinois as well as the federal government. On February 5, 1864, St. Louis received its charter from Missouri which stated in Section 6:
6. The said bridge shall be constructed of stone, iron and wood, but mainly of iron and stone. The company shall have power to determine and may determine and decide, by a vote of the majority in interest of the stockholders, what kind of a bridge shall be built, whether suspension, tubular, draw or otherwise, but whatever kind it may be it shall be so constructed as not to obstruct or impede the navigation of the river. If a draw bridge shall be decided upon it shall be built of sufficient capacity for a common wagon way and a foot passenger way, and may also be built of sufficient capacity for a railroad track or tracks for the passage of trains of freight and passengers, with spans not less than two hundred feet in length over the water, and shall have at least one draw, with two openings not less than one hundred feet in width each for the passage of steamboats or other vessels.
On February 20, 1865 this section was amended to read,
Sec. 6. The said bridge shall be built of such materials and upon such plan as the board of directors shall decide to be most suitable for the uses required of it, and it shall be of sufficient capacity to accommodate all the different kinds of travel, both common road and railroad travel, as well as foot passengers, that may require to cross upon it, and it shall be sufficiently high to admit of steamboats and all other river crafts passing under it at all ordinary stages of the river, when the chimneys, pipes and other projections are lowered down. The spans of the bridge between the piers and abutments shall be sufficiently wide to admit of all river crafts being easily navigated through them. The piers shall be so constructed as to obstruct the free flow of the current as little as possible.
On February 16, 1865, St. Louis received its charter from the State of Illinois, a portion of which stated:
AN ACT to empower the persons mentioned in an Act of incorporation, passed by the General Assembly of the State of Missouri, entitled “An Act to incorporate the. Saint Louis and Illinois Bridge Company,” approved February 5th, 1864, to form a corporation and build a Bridge across the Mississippi River at Saint Louis.
SECTION 1. Be it enacted by the People of the State of Illinois represented in the General Assembly, That the persons named in the act of incorporation granted by the General Assembly of the State of Missouri, entitled “An Act to incorporate the Saint Louis and Illinois Bridge Company,” approved February 5th, 1864, shall have the right to organize and form a corporation in accordance with the said act, to construct, maintain and use a bridge for railroad and other purposes over that portion of the Mississippi river at the city of Saint Louis, within the jurisdiction of the State of Illinois, subject to the conditions, terms and modifications herein set forth:
Provided, That said bridge shall not be located more than one hundred feet north or south of the dike or causeway upon which the ordinary travel is now conducted, and which connects Bloody Island opposite the city of St. Louis, aforesaid, with the main Illinois shore.
The Saint Louis and Illinois Bridge Company then went to Congress for approval. On July 26, 1866, Congress passed an act on bridges over the Mississippi River, stating with reference to the St. Louis Bridge:
Sec. 11. And be it further enacted, That the “ Saint Louis and Illinois Bridge Company,” a corporation organized under an act of the general assembly of the State of Missouri, approved February fifth, eighteen hundred and sixty-four, and an act amendatory of the same, approved February twentieth, eighteen hundred and sixty-five, and also confirmed in its corporate powers under an act of the legislature of the State of Illinois, approved eighteen hundred and sixty-four, or any other bridge company organized under the laws of Missouri and Illinois, be, and the same is hereby, empowered to erect, maintain, and operate a bridge across the Mississippi River, between the city of Saint Louis, in the State of Missouri, and the city of East Saint Louis, in the State of Illinois, subject to all the conditions contained in said act of incorporation and amendments thereto, and not inconsistent with the following terms and provisions contained in this act.
They were also required to adhere to Section 2 of that act that stated for unbroken and continuous spans:
it shall not be of less elevation in any case than fifty feet above extreme high water mark, as understood at the point of location, to the bottom chord of the bridge, nor shall the spans of said bridge be less than two hundred and fifty feet in length, and the piers of said bridge shall be parallel with the current of the river, and the main span shall be over the main channel of the river and not less than three hundred feet in length…
With these approvals in hand, St. Louis looked ready to prepare plans for the construction of the bridge. The city faced a setback, however, when a former ally and supporter of the bridge, Lucius Boomer (builder of the Rock Island Bridge), formed the Illinois and St. Louis Bridge company and obtained a charter from the state of Illinois that was silent with respect to spans, clearances, etc. since these had been set by the federal government on July 26, 1866. It did say, however, “The said corporation shall have the exclusive right for twenty five years of constructing a bridge opposite to the said city of St. Louis (in the county of St. Clair), over so much of said river as is within the jurisdiction of this State, and shall also have the right to protect the banks of the same so far as may be necessary to keep the channel within the opening of the bridge, and for that purpose may take and acquire lands and materials in the manner aforesaid. Provided, If the bridge herein authorized is not commenced in two years, and completed in five years, this act shall be null and void.” Boomer’s company was recognized as a private corporation for bridge building by Missouri in accordance with Chapter 69 on February 20, 1867.
On March 23, 1867, James B. Eads was selected as Chief Engineer. Eads has a long string of successes, but he had never designed or built a bridge, especially a double deck bridge to carry rail and road traffic similar to the Government (Arsenal) Bridge (STRUCTURE December 2023). He recruited Henry Flad, Charles Pfeifer, and W. Milnor Roberts as his assistants, and they made new surveys and borings. By July 15, Eads had some preliminary plans to show the directors. They included three long arch spans and foundations going down to bed rock. A local newspaper wrote of the plans, “What a triumph for St. Louis, the noblest river, the most glorious bridge, and the finest engineer in the world.”
While the design was progressing, Boomer was promoting a design of a three span Post Truss with two spans of 368 feet and one of 264 feet. He called together an elite group of engineers to compare his design with that of Eads. As would be expected, the engineers in a long report recommended Boomer’s plan.
Eads responded “If there were no engineering precedent for 500-feet spans, can it be possible that our knowledge of the science of engineering is so limited as not to teach us whether such plans are safe and practicable? Must we admit that because a thing never has been done, it never can be, when our knowledge and judgment assure us that it is entirely practicable?”
It was agreed that in order to remove this competition between the two plans a panel be formed to review them. It was clear, however, that the St. Louis & Illinois Bridge Company plan by Eads would win out and have them effectively purchase the rights of the Illinois & St. Louis Company for $150,000. In March 1868, the two companies agreed to a consolidation and accepted the Eads plans of the St. Louis & Illinois Bridge Company. On July 20, 1868, the Federal Government confirmed the consolidation and added the clause, “provided further that in construction said bridge there shall be one span of at least 500 feet between the piers.”
Jacob Hays Linville of the Keystone Bridge Company was called in as a consulting engineer to review Eads’ plans on the suggestion of Thomas Scott of the Pennsylvania Railroad. Linville didn’t think much of the plans and wrote, “I cannot consent to imperil my reputation by appearing to encourage or approve of its adoption. I deem it entirely unsafe and impracticable, as well as in fault in the qualities of durability.”
He then submitted his own set of plans for the bridges consisting of three trusses with curved top chords including the 500-foot central span. He even suggested an erection method by which the trusses would be fabricated off site, floated into place and lifted up by hydraulic jacks like Stephenson had done on his Menai Straits bridge, and placed on the piers. The Board, after reviewing Linville’s comments and plans, eliminated the position of Consulting Engineer. The three main innovative features of the plan were to use steel in his arch segments, to erect the arch segments by cantilever methods, and to sink the foundations by means of pneumatic caissons.
While the bridge was under construction, the War Department formed a panel of engineers to address the concerns of the steamboat companies. At the time, A. A. Humphreys, an arch enemy of Eads, was the Chief of Engineers. He appointed five officers to look into the following concerns:
(1) The height under the lower arch is so small that a large proportion of the boats which will have occasion to pass under it must lower their smoke-stacks at all, or nearly all, stages of the river, while many of the larger boats will not be able to pass under it during the higher stages, even with their smoke-stacks down.
(2) The small height afforded is only available for a portion of the whole span, owing to the arch-form of the lower part of the superstructure. Moreover, the difficulty of passing under the exact center of the arch will be very great, especially in foggy or windy weather, and any considerable deviation to either side may bring the boat’s upper works in contact with the Bridge.
(3) These difficulties would probably deter most boats from ever passing the Bridge, thereby preventing the ready transfer of freight from one boat to another, or its delivery and shipment at different parts of the city, without resorting to costly transfers by drays or barges. This, it is claimed, would practically cut the Mississippi River in two at this place.
They confirmed these concerns and concluded:
Under these circumstances, the board do not feel justified in recommending any change which would involve a complete remodelling of this magnificent structure, now so nearly completed. At the same time, as already stated, they deem it absolutely necessary that some provision should be made for allowing large boats to pass the bridge with safety whenever they find it necessary to do so.
They would therefore recommend, as the most feasible modification, a plan which has been already tried and found efficient at the railroad bridge over the Ohio River at Louisville, Ky.
Let a canal, or rather an open cut, be formed behind the East Abutment of the Bridge, giving at the abutment a clear width of water-way of 120 feet. The shore-side of this cut should be laid out on an easy curve, joining the general shore-line about five hundred feet above the Bridge and about three hundred feet below it. The river side may be entirely open, but the shore side should be revetted vertically with stone or crib-work to a height of about five feet above extreme high-water. This wall should be provided with ring-bolts and posts, to enable boats to work through the cut with lines.
Let this opening be spanned by a drawbridge giving a clear span of 120 feet in width.
By this plan, boats as large as any now built would be able to get through the Bridge, in any weather and at any stage of water, and only at the cost of some little delay.
The modification proposed by the board will not require the present work of constructing the Bridge to be interrupted, and the only action which seems necessary is to submit this matter to Congress at its next session, with the recommendation that action be taken to enforce the modification, and at the same time to determine by whom it shall be carried out.
Eads had a long response countering all their arguments and conclusions and went to see his friend President Ulysses S. Grant, who supported him. However, Congress did not take up the issue at its next session. This was another example of inconsistent governmental control and guidance of the design and construction of bridges across the Mississippi and other major rivers of the U.S.
Linville, who had reported unfavorably on the design by Eads, and the Keystone Bridge Company were chosen to build the superstructure. The problems Eads and his team had in sinking his caissons and obtaining the quality of steel he specified are described in C. M. Woodward’s, 1881 book, “A History of the St. Louis Bridge Containing a Full Account of Every Step in its Construction and Erection and Including the Theory of the Ribbed Arch and the Tests of Materials” and STRUCTURE Magazine, December 18, 2017.
After a period of construction starting in late 1867, the bridge opened on July 4, 1874. This was twice as long as Eads had estimated and at a cost of $6,536,729—twice what he had estimated. It was a financial disaster and the Bridge Company went into bankruptcy less than a year after it opened. However, the bridge still carries rail and motor vehicle traffic over the Mississippi. Using arches was a different solution than any previous or later bridges to cross the river, and as such was a dead end, but it did begin the use of steel as a material for bridge construction. It remains an icon of late 19th century bridge building. ■
About the Author
Dr. Frank Griggs, Dist.M. ASCE, specializes in the restoration of historic bridges, having restored many 19th Century cast and wrought iron bridges. He is now an Independent Consulting Engineer (fgriggsjr@verizon.net).