Tunnel Q's


New member
Can anyone please shed some light on (or in this case into) the below?

Why was the original Bozeman Pass Tunnel By-passed? I've not been able to find much information (or pictures) explaining why this was the case?

I've recently read that the Otira Railway Tunnel in NZ has been declared a "Fire Hazard" and as such, Passenger Trains are no longer allowed to pass through with passengers on board. Instead, people must now de-train at Arthur's Pass and ride by Bus over to the other side and pick up the train from there. Really... a Fire Hazard??? The Loco's are fitted with their own Fire retardent systems so no fire should spread from there one would think. No overhead cables now as they were all pulled out long ago so no risk of arcing or sparks. Makes me think that perhaps the hazard may in fact be a seismic one, afterall NZ is prone to earthquakes.

The Hermosa Tunnels are not that far from the ground surface above, so my question is, why not simply dig out a cutting? I'd have thought that building a tunnel is more expensive?

These are questions which have dogged me for ages, so am hoping anyone out there can point to the light at the end of these three tunnels!

Many thanks,
See: http://trn.trains.com/~/media/files/pdf/trains-grade-profiles.pdf

Page(s) 12 and 13, of 68

Before the turn of the 20th century, tunnels were very expensive ... but daylighting was almost impossible feat, with limited heavy duty earth moving technology.

I spend allot of time putting abandoned tunnels back into place, and back filling in the daylighting :hehe:

The C&O had steel mill fire retardant helmets for engine crews, fitted with oxygen hoses, to keep crews from being asphyxiated in long tunnels.

Some tunnels had poor rock quality, and were prone to collapse ... and others became obsolete due to excessive length, inadequate ceiling height, or had too steep of a grade
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