Sunday, March 30, 2014

A Tale of Two Tunnels: St Clair River

As we learned in our previous post, Seattle Tunnel Partners will need to excavate a large "retrieval shaft" in front of Bertha, their ailing Tunnel Boring Machine (TBM), to remove the Cutterhead and service or replace the Main Bearing.

I discovered that a similar incident took place in 1993 at Sarnia, Ontario. A TBM drilling a new railroad tunnel lost it's main bearing, and a retrieval shaft had to be constructed to remove the Cutterhead and replace the main bearing.

The Repair Pit has to be excavated ahead of the sick TBM. Then the TBM is driven through the wall into the Pit, to insure a seal between the TBM and the Pit wall, preventing incursion of soil material.

 At half the diameter of Bertha, Excalibore was down for nine months!

The Repair Pit was started on January 31, 1994.  The Cutterhead and Main Bearing were lifted out on June 30, 1994, and work completed three months later.  Burned up an additional USD4.2M.

Here is a sneak preview of what Seattle Tunnel Partners now facing.

Todays yarn explains why the Canadian National  was spending US160M to dig a new tunnel under the St. Clair River at Port Huron Michigan, next to the Grand Trunk Railroad Tunnel completed in 1890.

A major bottle-neck was created at the Sarnia - Port Huron  Ports of Entry, because excess height, auto rack, and double stack well cars, had to be barged across the St. Clair River.  Despite lowering the floor in 1949, they ssimply wouldin't fit in the aging tunnel.

The obvious fix was to dig a bigger tunnel, thereby eliminating the tugs and barges, vastly speeding up traffic. And so it came to be that on January 29, 1993,  the U.S. Army Corps of Engineers approved construction of a US$150M privately funded railroad tunnel under the St. Clair River. (Cost overruns brought the expenditure to US160M, the retrieval shaft.)

St. Clair River

The St. Clair River connects Lake Huron to Lake Erie, passing through Lake Saint Clair. The St. Clair River is about 39 miles long from Lake St. Clair via St. Clair Cutoff Channel and South Channel to the head of the river at Lake Huron. The lower 11 miles of the river is a broad delta through which numerous channels flow into Lake St. Clair. South Channel and St. Clair Cutoff Channel form the main navigation route through the delta and connect with the dredged channel across Lake St. Clair.

The banks of the river are clay and sand and usually quite steep.  The Federal project depth in the river is 27 feet.Lake Huron is at a stage of 578.9 feet (176.4 meters) and Lake St. Clair is at a stage of 573.9 feet (174.9 meters.)

Currents for Point Edward, head of the St. Clair River are given at high water flow of 230,000 cubic feet per second (cfs), medium water flow of 188,000 cfs, and low water flow of 130,000 cfs, respectively. Point Edward: 3.9 mph, 3.3mph, and 2.5 mph. The rapids section extends from about 1,000 feet above to 200 or 300 feet below the Blue Water Bridge.

Like the Detroit River, it sparks a lively debate as to whether these are "rivers" or "straits?"  A strait being defined as connecting two bodies of water. But I resist the urge to digress...

 In The Beginning 

The Grand Trunk Railway of Canada operated a large railway system by 1880, when it completed lines linking Chicago to the United States east coast. The railroad arrived at Sarnia Ontario in 1859.

On the opposite side of  the St. Clair River, the City of Port Huron incorporates on Feb. 4, 1857.

Chicago, Detroit & Canada Grand Trunk Junction Railway Co. begins construction of tracks 57 miles from Fort Gratiot (Port Huron) to Chicago via Detroit.

The first Grand Trunk train ran out of Chicago on Saturday night, February 7, 1880, arriving at Port Huron on Monday, February 9

From 1859 to 1890, freight and passengers were transported across the river between Port Huron to Sarnia, depending on railroad car ferries, creating a serious bottleneck for the Grand Trunk.

A car ferry was introduced that eliminated the need to unload and reload cargo as the new ferry could transport the railway cars themselves across the river.

But the ferry was unlike all others!

Swing Ferry

The swing ferry (reaction ferry) was anchored by a chain of about 1000 feet near the American shore, and, depending on her angle, was driven by the current in the rapids from one shore to the other. Her slips were at Point Edward, above Sarnia, and at Fort Gratiot in Port Huron, almost exactly at the piers of the present Blue Water Bridge.

Reaction ferries are not uncommon. There are five operating in British Columbia. But usually they are tethered to a shore-to-shore static cables. Here is the Lytton reaction ferry operates across the Fraser River in BC. Look carefully as the ferry returns.  You can see the overhead tethers (between red/white pylons,) and look carefully at the wheel house. You can see the skipper manipulating the rudder.

When river currents are two treacherous to run the ferry, passengers walk a detour. Canadian National built a protected pedestrian sidewalk next to the main line over the river.

A swing ferry at a point of such heavy traffic as the rapids presented a menace to navigation. About 1867, she collided with an upbound steamer, severing her chain, and drifting uncontrolled down the river. The schooner Reituker picked her up off Butler Street, Port Huron.

The vessel, the first of its kind, and the only one in the world for twenty years, was used constantly until the accident in 1867.

In 1872, the Grand Trunk prepared to retire the swing ferry, enlarge the slips at Poi nt Edward and Fort Gratiot, and put in service a self­ propelled car ferry, International.  She was constructed and deconstructed in Great Britain and shipped like a model kit to be reassembled in Port Huron.

St. Clair Tunnel

Steam ferries carried trains across the river until Sir Henry Whatley Tyler, president of the Grand Trunk Railway, decided that a tunnel was the solution to the untenable traffic jamb.

In October 1884, the Grand Trunk chartered the St. Clair Frontier Tunnel Company as a Canadian corporation to construct the tunnel and Tyler put Canadian engineer Joseph Hobson in charge of the project. The Grand Trunk also chartered the Port Huron Railroad Tunnel Company in Michigan in October 1886, and in November 1886, the railroad merged the twin companies to form the St. Clair Tunnel Company,

Hobson made two failed attempts to drive the tunnel by traditional means, from December 1886 - July 1887 and again in April - July 1888. After completing a detailed set of test borings along the tunnel route, Hobson decided to design a tunneling shield and to start tunneling from a point nearly one-third of a mile from the riverbank.

Identical Shields were launched in Sarnia and Port Huron, to meet mid-river.

The portions under the shore were driven without compressed air. But when the banks were reached, brick bulkheads containing air locks were built sealing the tunnel, and the section beneath the river, about 3,710 feet long, driven under air pressure of 10 to 28 pounds bar (above atmosphere.)

For most of the way, the clay was firm and there was little air leakage. It was found that horses could not survive in the compressed air, and so mules were used under the river.

Here be a  detailed document, Historical American Engineering Record - St. Clair Tunnel.  (HAER.)  From this document:

"Throughout the entire preliminary consideration of the project there was a marked sense of caution that amounted to what seems an almost total lack of confidence in success. Commencement of the work from vertical shafts was planned so that if the tunnel itself failed, no expenditure would have been made for approach work.

"In April 1888, the shafts were started near both riverbanks, but before reaching proper depth the almost fluid clay and silt flowed up faster than it could be excavated and this plan was abandoned. After this second inauspicious start, long open approach cuts were made and the work finally began.

"The portals were established in the cuts, several thousand feet back from each bank and there the tunneling itself began. The portions under the shore were driven without air. When the banks were reached, brick bulkheads containing air locks were built across the opening and the section beneath the river, about 3,710 feet long, driven under air pressure of 10 to 28 pounds above atmosphere. 

"For most of the way, the clay was firm and there was little air leakage. It was found that horses could not survive in the compressed air, and so mules were used under the river. In the firm clay, excavation was carried on several feet in front of the shield.  About twelve miners worked at the face. However, in certain strata the clay encountered was so fluid that the shield could be simply driven forward by the rams, causing the muck to flow in at the door openings without excavation. After each advance, the rams were retracted and a ring of iron lining segments built up, as in the Tower Subway. Here, for the first time, an "erector arm" was used for placing the segments, which weighed about half a ton.

"In all respects, the work advanced with wonderful facility and lack of operational difficulty. Considering the large area, no subaqueous tunnel had ever been driven with such speed. The average monthly progress for the American and Canadian headings totaled 455 feet, and at top efficiency 10 rings or a length of 15.3 feet could be set in a 24-hour day in each heading. The 6,000 feet of tunnel was driven in just a year; the two shields met vis-à-vis in August of 1890."  From "Tunnel Engineering. A Museum Treatment," Robert M. Vogel, 2012.

"The observation of the direction of the shield was very interesting. From a small house in the line of the tunnel these observations were taken every morning. The transit was a fine one, made especially in London, and was set on masonry. A series of disks and a tube with cross wires enabled the engineer to discover, to the smallest fraction of an inch, any deviation in the direction of the shield. This deviation was marked on a diagram. One copy was sent to Chief Engineer Hobson at Hamilton and one was left at the works. The man in charge of the hydraulic rams was informed of any variation in the shield and he adjusted the jacks to correct any error. This deviation was rarely more than a quarter of an inch. When the two TBM's met, they were perfectly aligned horizontally, 1/4" off vertical."   (From Launceston Examiner, Dec. 31, 1891.)

The two shields met on 30 August 30, 1890 and the St.. Clair Tunnel officially opened on September 19, 1891. Hobson had successfully combined three innovative techniques for the first time in the construction of a large-size subaqueous tunnel:

•  Use of tunneling shields
•  Cast iron tunnel lining
•  A ccompressed air work environment

This series of photographs were taken in 1993, to accompany the Historical American Engineering Record.

Tunnel of Death

"Although the tunnel locomotives burned either coke or anthracite coal to reduce smoke emissions, the locomotives nevertheless produced carbon dioxide and carbon monoxide. Both gases can cause death. The ventilation system normally took 45 minutes to clear the tunnel of all gases after a train had passed through. Joseph Hobson, Tunnel Project Engineer, testified in 1897 that he had removed the original ventilating pipes after only a few years of use because they worsened tunnel ventilation. 

"If a train passed through the tunnel without delay, the gases did not pose a threat to life. However, as a locomotive was ascending the incline leading out of the tunnel, the couplers connecting the cars were subject to great strains and would often break, leaving part of the train behind in the tunnel. This would endanger the conductor and brakeman, who normally worked from the caboose, as well as the locomotive engineer and fireman if they returned to the tunnel to retrieve the missing cars.

"The first fatal accident: occurred on 31 January 1892, only three months after the tunnel opened to regular freight traffic. Following a train break in the tunnel, conductor George Hawthorne and brakeman Joseph Whalen were overcome by fumes and Hawthorne died. 

"The breaking of couplers in the tunnel became so commonplace that more fatal accidents were inevitable. In the four years ending 30 June 1899, for example, when nearly 16,000 trains traversed the tunnel each year, a total of 278 trains broke apart in the tunnel, roughly 70 per year. 

"A second and more serious accident, took place on November 29, 1897, resulting in the death of three men, including the engineer, one brakemen, and the conductor. 

"The third and the worst accident happened on October 9, 1904, resulting in six deaths, including two brakemen, two conductors, the locomotive engineer, and the superintendent of the Sarnia and Port Huron terminals, Alexander S. Begg. (Complete incident details, The Post Standard, Syracuse New York.)

"In the wake of the third fatal accident, Grand Trunk moved quickly to convert the tunnel to electric traction. In December 1904, General Electric and Westinghouse, submitted proposals to electrify all tunnel operations.

"Grand Trunk specified that the electric haulage system must, be able to pull a 1,000-ton train between the two tunnel terminals in 15 minutes, and maintain a train speed of at least 10 miles per hour up the 2 percent grade leading out of the tunnel.

"General Electric proposed a DC system of 600 volts using a third rail, but the Grand Trunk accepted the Westinghouse proposal based on the use of a 3,300-volt AC single-phase system,[overhead trolley]. 

"According to the Port Huron Daily Times, the entire project cost more than $1 million. Although the Grand Trunk signed the electrification contract with Westinghouse in January 1906, the first electric locomotive did not pull a freight train through the tunnel until 20 February 1908." 

This tunnel has undergone only minor changes since its opening. The railroad lowered the tracks in 1949 to allow taller freight- cars to use the tunnel. Diesel locomotives went into service in September 1958 and the railroad installed new ventilation equipment to handle the diesel fumes.

Despite the tunnel, excess height, auto racks and double-stack rail cars moving between Michigan and Canada still had to be loaded onto barges and "floated" across the St. Clair River. So Canadian National decided to bore a new tunnel under the river, eliminating the choke point. On January 29, 1993, the U.S. Army Corps of Engineers approved construction of a US$150M railroad tunnel under the St. Clair River, funded by CN.

Like Seattle's "Bertha," CN's "Excalibore" lost the main bearing seal. Fortunately, the Tunnel Boring Machine (TBM)  was not under the river. Stalled beneath an Esso (Imperial) oil refinery at Sarnia, a retrieval pit was constructed to allow access to the Cutterhead, which was removed to gain access to the main bearing. The repair took nine months - a hint of what Seattle Tunnel Partners are facing.

"Excalibore," the TBM broke through at Port Huron on December 8, 1994 and the new tunnel was dedicated on May 5, 1995. The original tunnel was retired and filled in with sand.

The new tunnel measures 6,129 feet (1,868 m) from portal to portal with a bore diameter of 27 feet, 6 inches (8.4 m) with a single standard gauge track.

On November 30, 2004, the tunnel was renamed in honor of Paul Tellier, the CEO of Canadian National Railway (CN) from 1992 to 2002 and the man who had the new tunnel built.

And the tug and barge "fleet" was retired. Eliminating the barge operation cuts 12 hours shipping time between Chicago and Toronto, a significant saving to customers.

CN rail tugs laid up at Sarnia. March. 25, 1995.

This video was shot at approximate location of the anchorage for the Swing ferry at Fort Gratiot in Port Huron. This is the outlet of Lake Huron, hence the "headwater" of the St. Clair River. You can clearly see the velocity of the current.

Students of geography struggle with the notion of the St. Clair River being a "river" or a "strait."  A strait joins two bodies of water, whilst a river has a point of origin at elevation, with gravity propelling it to a static level. This argument also shadows the Detroit "River."

The Blue Water Bridges can be seen, the nearest bridge opened in 1938, the distant bridge opened in 1996.

And here is a totally awesome video taken from the bridge of a Great Lakes freighter, entering the 800 foot wide St. Clair River. Average current 4 mph.  That means the freighter must double that speed in order for her to respond to rudder commands!

Tunnel Action!

This video feartures a southbound Canadian National freighter exiting the St Clair Tunnel on the Port Huron side of the "river."

In this video, another freighter descends the 2% grade down to the tunnel under full dynamics!  When the camera view switches to the tunnel, just beyond the flag pole is the Esso Refinery. That is where CN's Tunnel Boring Machine "Excalibore" was stuck for nine months. Toward the end, a great comparison of the new bore next to the original bore.

Baffled by the strange cargo near the end of this clip, I turned to my contemporary up in the Great White North, who explained "Auto frames on Trailer Train flat cars."

To this day, it is uncomfortable for me to witness a train without a caboose ...

Finally, the obligatory train ride through the tunnel. Watch for "the light at the end of the tunnel."

Saturday, March 1, 2014

"Get Your Tracks out of Town!"

Massive Remediation of Crude Oil Damage
Lac-Mégantic Mayor to Railway:  "Get Your Tracks out of Town!"

Lac-Mégantic is still recovering from a fiery train disaster last July [2013], when a Montreal, Maine & Atlantic runaway train devastated the bucolic lakeside town. 

Mayor Colette Roy-Laroche says she made it clear to the railroads new owner that she - and the residents of  Lac-Mégantic - want the tracks out of town!

A Lac-Megantic town official says Mayor Colette Roy-Laroche delivered the message this past week during her first meeting with a representative for Fortress Investment Group, the winning bidder for the insolvent Montreal, Maine & Atlantic Railway.

The Lac-Mégantic official says the mayor also made it clear during her "positive'' exchange with Fortress consultant John Giles on Monday [February 24] that locals no longer want crude oil transported through the middle of the community!

Former Montreal, Maine & Atlantic, former BN 5016, tip toes past a gathering of  news media. I am sure the locomotive operator was feeling uncomfortable, knowing  the residents are not at all pleased to see a train in town.

 Where Did the Oil Go?

Last July's derailment, that saw 63 tank cars carrying Bakken Shales crude oil accordion derail and explode in downtown Lac-Megantic,

•  Killed 47 souls.
•  Destroyed 40 structures.
•  Damaged 160 structures.
•  Spilled 1,300,000 US gallons (5,600,000 litres).
•  Covered 32 acres (31 hectares).
•  Contaminating 558,000T (506,209t) of soil.
•  Impacting the flora and fauna.

What Remediation Does to a Town

Every last teaspoon of soil - 558,000T (506,209t) - needs to be removed for remediation, or remediated "place."  Here is a detailed assessment of the what needs to be done to reclaim Lac-Mégantic. This isn't a "lab experiment."  This is a real town, with real people.

Too often we look at photos like these with a sense of detachment. I want you to look at these photos, and think about how you would feel if this was YourTown USA. 

Hideous ex-situ scar at epicenter of derailment
A tiny part of 500,000T of soil awaiting remediation
Personal vehicles and land - gone!

None of this would have happened if  Edward Burkhardt had not taken over this road, and run it into the ground with his preposterous notion that one man can run a train!

•  47 people would be alive.
•  40 structures would be standing.
•  160 structures would be functioning. 

As Seen From Space

Following the train disaster in Lac-Mégantic on July 6, 2013, the International Charter on Space and Major Disasters was activated by Public Safety Canada, to assess the scope of the disaster.

QuickBird-2, the worlds highest resolution satellite camera, captured these "before" and "after" views of Lac-Mégantic. Click on each image to experience the high resolution of QuickBird-2's camera.

QuickBird-2, owned and operated by DigitalGlobe, Longmont Colorado, launched into its 280 mile (450 km) orbit from Vandenberg AFB aboard a Delta II vehicle, in 2001.  2014 is anticipated to be the final year of operation, due to its deteriorating orbit.

Here is an interesting "primer" on satellite imaging. Google Earth now shows Lac-Mégantic after the wreck, taken July 12, 2013.

Type Lac-Mégantic into Blog Search Engine in right column, to access all articles pertaining to this disaster.