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Mackinaw Bridge Question

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Mackinaw Bridge Question
Posted by Bruce Frierdich on Thursday, July 4, 2019 12:29 PM

Hi all. Happy Fourth of July!  Question about the Mackinaw Bridge. Back when the bridge was built, the DSS&A, Soo, Milwaukee and CN&W (I believe) dropped cars on ferries that then crossed Lake Michigan or the straits of Mackinaw and interchanged with the NYC, Penn, and C&O in Lower Michigan which took ore to mills and products off to points east and south.  My specific question: why didn’t they include tracks when they built the bridge with some kind of sharing arrangement?  Would have made a lot of sense at the time. (Not so much now.....)  I could swear I saw a drawing once of a steam locomotive crossing the straits.  Does anyone know?  Thanks. 

Bruce

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Posted by tree68 on Thursday, July 4, 2019 12:38 PM

The weight carrying capacity involved for railroad equipment would have increased the cost of the bridge by an order of magnitude or two.

If it was at all considered, I'd opine that they found that the ROI was in negative numbers.

The Chief Watawam wasn't exactly overtaxed moving cars across the straits.  And there were (and are) a couple of overland routes available for reaching the UP.

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Posted by Erik_Mag on Thursday, July 4, 2019 12:48 PM

Railroad bridges, and especially bridges carrying freight trains, need to be much stiffer than a typical road bridge. Suspension bridges tend to be on the flexible side and are not suited for normal railroad use, exception being transit.

A railroad crossing of the straits would more likely have been done with a tunnel.

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Posted by Overmod on Thursday, July 4, 2019 1:14 PM

Erik_Mag
Suspension bridges tend to be on the flexible side and are not suited for normal railroad use, exception being transit

A better way to put this is that suspension bridges for railroad use have to be 'purpose-built' in particular ways, including relatively low approach and departure grades and limited deflection under 'worst-case' distribution of live load.  See Lilienthal's last proposal for a Hudson River crossing for an example of what should be involved.

The reserved structure on the George Washington Bridge (for extension of the IND service) was a good example of fairly-heavy construction with otherwise comparatively thin road-deck structure (it is difficult to remember how slim the deck appeared before the edge trusses for the lower-deck 'Martha Washington Bridge' were installed in the early Sixties).  I don't recall seeing the anticipated operating restrictions for number of trains on the bridge, but the original R1s were not light 'per foot'.

The important point about the 1957 bridge in particular was that it was designed with long spans to minimize the number of piers subject to winter ice forces.  An earlier plan had a double track in deep trusses, but this would have required a pier at the deepest point in the Strait, and this was a greater problem than the issues involved in highway-optimized long-span integrity.  (This bridge came soon enough after Tacoma Narrows that Steinman used careful design of airflow effects in construction; this would lead to problems for one Yugo driver later on).

(It might have been interesting if the Vanderbilt who proposed building a Forth-like cantilever bridge across the Strait had done so -- this would have been an obligate rail structure at the time, and perhaps uncharitably I think it would have encountered as many 'construction issues' as the Quebec Bridge.)

I dont know if water flow or other considerations in the Strait would rule out the kind of 'floating' retractible bridge like the one across the Hood Canal, perhaps in conjunction with the causeway system built earlier.  That would be inherently suited for even high-speed rail.

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Posted by tree68 on Thursday, July 4, 2019 3:23 PM

Overmod
I dont know if water flow or other considerations in the Straits

Had to look that one up.  

Contrary to what might seem logical, the current in the Straits of Mackinac run in both directions, based on wind direction, among other factors.  According to one source, it changes about every day and a half.  We see the same thing along the length of Lake Ontario.

Flows can be as high as 1 meter per second, or about 2.2 MPH.

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Posted by Overmod on Thursday, July 4, 2019 3:43 PM

tree68
Had to look that one up.

Sorry, forgot I hadn't finished that line. 

I don't know in particular if a floating bridge could be made to handle the substantial ice that forms ... and moves ... in that area at some points in the year.  Steinman's bridge, of course, stays above it, but using a grade profile that would be difficult to adapt to practical rail access to the Yoop.  If you could close the bridge (or more precisely, lock it open or remove the floating sections to a 'safer' location for them) at critical times, it would be more 'thinkable' ... but who needs a rail-capable part-time bridge when a car-and-truck optimal (again, that's if you're not driving a Yugo or similar car!) alternative can be full-time.

 

I wonder if Mike knows if one of the pictorial bridge catalogues of the period has a drawing or other plan of Vanderbilt's Strait bridge proposal.

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Posted by tree68 on Thursday, July 4, 2019 5:26 PM

This does raise another question, though.  What if a rail capable link (bridge, tunnel) had been built across the strait?  How would this play, specifically, with iron traffic (ore, taconite)?  Clearly, it could run year-round (snow notwithstanding), which would put it in conflict with the water shipping industry.

Someone with more knowledge of potential shipping rates than me would have to figure out which was advantageous.  The fact that trains could run year-round would  take away the need to stockpile ore/taconite at ports for eventual shipment to the mills, f'rinstance.

Many considerations.

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Posted by MidlandMike on Thursday, July 4, 2019 8:33 PM

I think lake ice would rule out any practical float bridge.  Ice floes may be many square miles, and a wind blowing across that much surface area will make the ice an unstoppable force against a 5 mile long floating bridge.  The ice will break-up around a bridge pier, but the only linear thing that will stop it is the shore, where ice will brake up and pile up as the floe keeps moving in.  Sometimes the news will show beach houses, where the ice is piling up as high as a 2 story building.  I remember one bad ice year, the Ann Arbor car ferry could not get out of the Frankfort harbor because the built-up ice was dragging on the bottom of the harbor.

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Posted by MidlandMike on Thursday, July 4, 2019 8:39 PM

Erik_Mag
A railroad crossing of the straits would more likely have been done with a tunnel.

The Straits of Mackinac are over 250' deep closer to the lower peninsular side.  The tunnel would have to be somewhat longer than the 5 mile crossing to keep grades reasonable.

Edit: there is a tunnel proposal for relocating an oil pipeline, that presently runs across the bottom of the Straits.  Its 60 years old and recently was dinged by a dragging anchor strike. 

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Posted by MidlandMike on Thursday, July 4, 2019 9:07 PM

A note on spelling.  The Straits and Bridge retain the french root spelling of Mackinac.  The City on its south shore uses the english phonetic spelling of Mackinaw.  They are all pronounced as the latter.

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Posted by Overmod on Thursday, July 4, 2019 11:14 PM

MidlandMike
 
Erik_Mag
A railroad crossing of the straits would more likely have been done with a tunnel. 

The Straits of Mackinac are over 250' deep closer to the lower peninsular side.  The tunnel would have to be somewhat longer than the 5 mile crossing to keep grades reasonable.

If I recall correctly, the proposal was for a floating tunnel, a bit like a neutral-buoyancy enclosed bridge far enough under the water to clear any passing ship traffic, presumably with ballasted anchors used to adjust its geometry periodically.  (A similar arrangement features in the great Harrison alternate-history SF novel "A Transatlantic Tunnel, Hurrah!")

The costs associated with the approach and departure grades for a true submerged 'tunnel' far enough below the Strait (I use the singular because there's only one where the bridge or tunnel location is) would be more extreme, by 1957, than I suspect the convenience of the tunnel connection would provide in operating revenue.  It certainly wouldn't have been built to stack clearances or be easily adapted to them!  Theoretically at least the replacement segments of a 'floating' road and rail tunnel could be fabricated and installed comparatively easily ... if demand warranted, perhaps as part of a road-widening project.

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Posted by Erik_Mag on Friday, July 5, 2019 12:21 AM

Looking at a couple of 1:24000 topo maps of the straits, the depth soundings sort of suggest that a route a mile to the east or west may results in a shallower tunnel.

On another note: Why am I not surprised that you would have read Harrison's "A Transatlantic Tunnel, Hurrah!"... The evolution of tunneling technology in the book reminded me of the "Tale of two Tunnels" series in Trains from the mid-60's. Not sure where he got the idea for pulverised coal powered dirigibles.

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Posted by Bruce Frierdich on Friday, July 5, 2019 12:54 AM

Hi. Thanks all for helpfull information. The gist is that a bridge for auto and truck traffic couldn’t support railroad traffic And there were no other practical solutions. With the iron ore business down and not much else happening in the UP, the interest is probably purely academic at this point. 

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Posted by Leo_Ames on Friday, July 5, 2019 2:08 AM

I'm not sure it would make sense even back when 90 million tons of ore would be locked through the Soo each shipping season. I suspect the savings of going by lake freighter would more than compensate for the need to stockpile ore for the three month or so off season.

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Posted by beaulieu on Friday, July 5, 2019 6:55 PM

No Iron Ore traffic used the ferry ever. Iron Ore traffic was transloaded to lake freighters at Ishpeming(on Lake Superior), Escanaba, or Gladstone, all in Michigan. Only DSS&A, or after the merger Soo Line served the ferry on the north. Traffic was mainly passengers, pulp, paper, and lumber, after World War II. Passeenger cars stopped using the ferry around the time of the Korean War, though passengers could disembark from railcars at either end and use the ferry as foot customers, rembarking after using the ferry as connecting service was maintained for a few more years.

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Posted by MidlandMike on Friday, July 5, 2019 10:29 PM

beaulieu
No Iron Ore traffic used the ferry ever.

Well at least once it was tried in the early days of the Straits ferry.  Unfortunatly a string of ore cars was poorly placed on the ferry and caused it to capsize in the dock.  Some ore for Ford was also carried on the Ann Arbor ferries out of Manistique, but the experiment was short lived.

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Posted by CSSHEGEWISCH on Monday, July 8, 2019 8:33 AM

MidlandMike
 
beaulieu
No Iron Ore traffic used the ferry ever.

 

Well at least once it was tried in the early days of the Straits ferry.  Unfortunatly a string of ore cars was poorly placed on the ferry and caused it to capsize in the dock.  Some ore for Ford was also carried on the Ann Arbor ferries out of Manistique, but the experiment was short lived.

 
According to "The Great Lakes Car Ferries" by George W. Hilton, the capsizing due to poor loading of ore jennies happened to "Ann Arbor 4" at Manistique.
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Posted by Bruce Frierdich on Monday, July 8, 2019 11:00 PM

Hi. Probably showing my ignorance here but I believe the ore was transported from mine to loading docks to ore boats and off to destinations like Gary or Cleveland basically from spring to fall but transported by train in winter. in ‘64-‘67 we lived a few hundred yards from the CNW line that ran north through Milwaukee and on up to the UP. I recall seeing those trains and finding taconite pellets along the track. I’m guessing it was cheaper to use ore boats unless Mother Nature interfered. 

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Posted by Steve B500 on Monday, July 8, 2019 11:20 PM

Starting in Feb. 1965, Ann Arbor's subsidiary Manistique & Lake Superior RR hauled ore to the AA ferries when the Soo Locks closed for the winter. From Frankfort, AA trains took it south, then on the DT&I to Ford. Over 160,000 tons were hauled between Dec. 1965 and Feb. 1966. Unfortunately, ML&S's track was so bad there were too many derailments, and the traffic shifted to CNW-N&W after the winter of 1966-1967 (source: book "The Haywire" by Hugh Hornstein).

I'd be very reluctant to claim that no ore traffic ever used the Mackinac rail ferries in their 96 years of service. Especially since George Hilton explains in "The Great Lakes Car Ferries" regarding the ferry "St. Ignace": "On June 10, 1902, when she was being loaded with ore cars at St. Ignace, the switching crew made the cardinal error of loading all of one track first...with iron ore it proved disastrous."

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Posted by CMStPnP on Tuesday, July 9, 2019 2:56 AM

I tend to think that the amount of traffic never warranted a bridge or tunnel.

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Posted by Backshop on Tuesday, July 9, 2019 6:17 AM

CMStPnP

I tend to think that the amount of traffic never warranted a bridge or tunnel.

 

This is the correct answer.  Both sides of the bridge were located at the end of long, lightly built branch lines.

By the time the bridge was built, the steel companies had spent large amounts of money on Lakes boats, port facilities and railroads to transport the ore from the docks.

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Posted by Bruce Frierdich on Tuesday, July 9, 2019 9:30 AM

Hi. Yes but.... I have to wonder if there was a means to avoid Chicago whether more mixed traffic might have taken that route justifying better track — for example agricultural products from Canada to east coast.   Just wondering. 

Bruce

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Posted by Bruce Frierdich on Tuesday, July 9, 2019 9:33 AM

One other thing — there is a nice POV article in the current Trains magazine about chasing trains in the UP in the ‘60s. 

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Posted by CSSHEGEWISCH on Tuesday, July 9, 2019 10:05 AM

Bruce Frierdich

Hi. Yes but.... I have to wonder if there was a means to avoid Chicago whether more mixed traffic might have taken that route justifying better track — for example agricultural products from Canada to east coast.   Just wondering. 

Bruce

 
That was pretty much the role of the Pere Marquette and Ann Arbor carferries across Lake Michigan.
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Posted by Backshop on Tuesday, July 9, 2019 10:09 AM

The other thing that helped the carferries was the ICC rate divisions.  Once the industry was deregulated, away went the ferries.

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Posted by tree68 on Tuesday, July 9, 2019 12:26 PM

Bruce Frierdich

Hi. Yes but.... I have to wonder if there was a means to avoid Chicago whether more mixed traffic might have taken that route justifying better track — for example agricultural products from Canada to east coast.   Just wondering. 

Bruce

I would opine that had a tunnel been built across the straits at around the time the St Clair (Port Huron - Sarnia) and Michigan Central (Detroit - Windsor) tunnels were built, such traffic may well have taken that route, and the lines supporting it would have been built up appropriately.  

Of course, there's a lot of "what if's" there, but it's a consideration.

And there is a rail bridge across the St Mary's River at the Sault.

 

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Posted by MidlandMike on Tuesday, July 9, 2019 9:20 PM

Bruce Frierdich

Hi. Probably showing my ignorance here but I believe the ore was transported from mine to loading docks to ore boats and off to destinations like Gary or Cleveland basically from spring to fall but transported by train in winter. in ‘64-‘67 we lived a few hundred yards from the CNW line that ran north through Milwaukee and on up to the UP. I recall seeing those trains and finding taconite pellets along the track. I’m guessing it was cheaper to use ore boats unless Mother Nature interfered. 

 

There were certainly all-rail movements of ore in the winter.  However, the Soo locks were only shut down for about 2 months, between mid Jan. and mid March.  Also ore boats out of Escanaba on Lake Michigan had a longer season.

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Posted by Miningman on Tuesday, July 9, 2019 9:55 PM

Iron Ore

 
1) PRR Iron Ore Ad
2) The Steep Rock Iron Ore Mine 
 

 

 
 
 
 
 
 
 
 
 
 
 
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Posted by CMStPnP on Wednesday, July 10, 2019 6:49 AM

They had Iron Ore piers all over the place to transfer the ore to Lake Michigan ships, Duluth, Ashland, Marinette, etc.   I'm sure there were more locations than that.    I always wondered why C&NW built to Ashland,WI and the answer was the railroad was thinking Iron Ore traffic.   The other reason for all the rail lines in the UP and Northern Wisconsin was timber for the Fox River Valley paper companies and for construction materials.....railroad ties, board siding, lumber, etc.     

When I attended college in Milwaukee in the late 1980s the Fox River Valley Paper Companies were still a big employment draw for University of Wisconsin's Engineering program.   Much more so than the automobile industry.    Quad Graphics just out in Milwaukee's Suburbs was a large Soo Line customer of large paper rolls from the paper companies further North.    They had two main plants, one in Sussex, one in Duplainville.   Between the two plants they consumed a fairly long train of boxcars per week filled with paper rolls.    I worked in the plant as a temporary laborer one summer.    They specialized in color print publishing and published a number of color Magazines including most of the Kalmbach line, including TRAINS, TIME Magazine, New Yorker, Hustler, Playboy, Newsweek.   Also catalogs such as SEARS and SEARS Christmas wishbook, etc.    Ship in raw materials by rail and ship out publications on trucks.    There was another large publisher on the Milwaukee Road airline between Elm Grove and West Allis.   The Kreeger Company, they published Readers Digest and associated Readers Digest publications, Home and Garden and some other stuff.     So lots of Box Car rail traffic between the Fox River Paper Plants and suburban Milwaukee and even farther because Quad Graphics also had plants in upstate New York.    Heck one of the plants up there makes Huggies disposable diapers even.    Pretty sure that is shipped out in part via rail.    I am sure CN still handles a lot of business from those paper plants though their shipments have shrunk probably since the 1980's due to the internet.    You can still see on youtube long E&LS trains from the UP loaded with pulp wood headed for Green Bay paper plants and paper plants further South on CN (Appleton, WI for example).

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