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General railway discussions

Northern Light

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Not necessarily tunnelling - but monitoring and if necessary strengthen the slopes; designing for greater peak flows for bridges, etc. Extreme events like these will likely be more frequent going forward - and this is a wakeup call.

AoD

There's not a lot that can be done to strengthen the slopes here. (practically)

Its a natural phenomenon that trees/vegetation anchored in relatively thin soils over rock have comparatively low adhesion. In the event of heavy water flow down a steep slope, there simply isn't any ability for the vegetation to hang on. The soil (or mud) and some loose rock is on its way down, and trees are going with...

Reducing clear-cut logging, in some spots, would provide some protection, in lighter rain situations (live vegetation roots do provide some anchoring); but it wouldn't do much against the kind of weather BC just saw.

You can certainly improving monitoring, and you can widen bridges some, as well as re-enforce their piers to take a direct blow from a slide or a torrent of water..........

But given the sheer number of potential problem points, I'm not sure that's cost-effective at scale.
 

AlvinofDiaspar

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There's not a lot that can be done to strengthen the slopes here. (practically)

Its a natural phenomenon that trees/vegetation anchored in relatively thin soils over rock have comparatively low adhesion. In the event of heavy water flow down a steep slope, there simply isn't any ability for the vegetation to hang on. The soil (or mud) and some loose rock is on its way down, and trees are going with...

Reducing clear-cut logging, in some spots, would provide some protection, in lighter rain situations (live vegetation roots do provide some anchoring); but it wouldn't do much against the kind of weather BC just saw.

You can certainly improving monitoring, and you can widen bridges some, as well as re-enforce their piers to take a direct blow from a slide or a torrent of water..........

But given the sheer number of potential problem points, I'm not sure that's cost-effective at scale.

They'd have to assess the slopes along the entire route - some may get away with maintenance of vegetation; others may require more aggressive intervention.

Well, I am sure someone can add up the cost of doing all these improvements vs. the repair as is cost of this plus the economic loss from the disruption of this corridor - and sometimes, national infrastructure isn't just a matter of cost-effectiveness.

AoD
 

Allandale25

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FB_IMG_1637195662944.jpg

FB_IMG_1637195665750.jpg
 

lenaitch

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They'd have to assess the slopes along the entire route - some may get away with maintenance of vegetation; others may require more aggressive intervention.

Well, I am sure someone can add up the cost of doing all these improvements vs. the repair as is cost of this plus the economic loss from the disruption of this corridor - and sometimes, national infrastructure isn't just a matter of cost-effectiveness.

AoD
And that seems to be part of the problem. Most western democracies haven't had a really serious discussion about the national security angle of much of our privately owned critical infrastructure. In this context, "national security" is meant in its broadest sense; the impact on our economy and way of life.

Railways are pretty adept at getting lines back in service from major disruptions, at least temporarily. Highways perhaps not so much as many of the bridges are bespoke (for want of a better term) with concrete girders and such engineered for each specific site. I think one of the choke points for all of the corridors will be the massive demand for clean, stable fill. A lot of what the corridors were based on is now downriver and fouled.

Although the amount of rain was probably overwhelming regardless, I have to believe a couple of seasons of wildfires hampered the ground's ability to remain stable in some areas.
 

lenaitch

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I was reading on another forum that BC has a stockpile of Acrow bridging sections (the modern version of the WWII Bailey Bridge) so it would seem that if the anchor points can be stabilized, recovery and reconnection - is some sense anyway - could be accelerated. The longer the span, the bigger the problem. I don't know how suitable they are for rail but they usually have a quantity of their own bridge panels.

 

crs1026

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Good news about Churchill. Though perhaps not the best timing with all the supply chain issues.

But glad to see they are doing this right! Bodes well for the future. I wonder if that could lead to travel time improvements.

The navigation season at Churchill is pretty much over for this year, so I don’t think this is really much of a delay… more just acknowledging that work can’t be done over the winter season.

- Paul
 

crs1026

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The rough distance through Canada's Mountains is ~600km from just east of Canmore to just west of Vancouver.
Now, clearly, not every section would meet the criterion for tunnelling.......

Still, if you went with that for even 1/2 the distance, where it would mitigate the most risk, or generate the most travel savings...........
You're looking at well north of $100B USD in today's $ on a go-forward basis.

Normally I don't indulge in fantasy discussions... but I come back to this one. Tunnelling through the mountains does not limit us to existing routes or mountain passes.

Straight line from Hope BC to Creston BC is only 223 miles.

Just Sayin'

- Paul
 

roger1818

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Normally I don't indulge in fantasy discussions... but I come back to this one. Tunnelling through the mountains does not limit us to existing routes or mountain passes.

Straight line from Hope BC to Creston BC is only 223 miles.

Just Sayin'

- Paul

Agreed. Alternatively, from Hope to Kamloops (and thus usable by both CN and CP since they already have a track sharing arrangement for most of the route anyway) would be about 165km (about 100 miles). The Fraser Canyon is the most vulnerable section anyway.
 

Northern Light

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roger1818

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An update on highway 1 / cn crossing in BC:


https://flic.kr/p/2mKt2yU
A whole ton of damage pics are here: https://www.flickr.com/photos/tranbc/albums/72157720143417483/with/51688211010/. This could take a while to fix. Shocked the underpass has not yet collapse. That is one well built underpass.

Looking at Google maps, it seems as though it is an old ravine that was backfilled when the railway was built (what could go wrong doing that? :rolleyes:). The way that has washed out, I can't help but wonder if the best long term solution would be to build a dual level bridge that spans the ravine and allows the road to pass under the tracks (or if possible, redesign the section to not have the highway and tracks crisscross, as they swap sides again about 4km east). That would take a long time to design and build though.
 

crs1026

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Looking at Google maps, it seems as though it is an old ravine that was backfilled when the railway was built (what could go wrong doing that? :rolleyes:). The way that has washed out, I can't help but wonder if the best long term solution would be to build a dual level bridge that spans the ravine and allows the road to pass under the tracks (or if possible, redesign the section to not have the highway and tracks crisscross, as they swap sides again about 4km east). That would take a long time to design and build though.

I suspect Van Horne didn’t have access to ”once in a hundred years” engineering calculations for water flow in creekbeds along the canyon ;-)

Seriously, if we believe that climate is changing and these events will become more frequent, it does imply that we will have to revisit the engineering assumptions for every inch of the rail network. .Civil engineers are taught, don’t mess with water.

- Paul
 

Northern Light

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I suspect Van Horne didn’t have access to ”once in a hundred years” engineering calculations for water flow in creekbeds along the canyon ;-)

Seriously, if we believe that climate is changing and these events will become more frequent, it does imply that we will have to revisit the engineering assumptions for every inch of the rail network. .Civil engineers are taught, don’t mess with water.

- Paul

The most severe flooding in BC is the result of a choice decades ago to drain a local lake which used to hold the area floodwaters.

Oops

In my experience Engineers love messing w/water...........even though they have a really bad habit of getting it wrong.

See New Orleans Levees, Over topped Levees along the Mississipi and in Quebec, the Black Creek Culvert at Finch West, in Toronto that blew out, and Site C Dam in BC amongst others. .
 

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