Cutting the tunnel

[redlynx]

Does anyone really know what "cutting" the Stampede Tunnel really entails? There will be a lot more involved than notching it. I do recall that it is relatively tight fit for the GEs and other large engines, and that oversize cars, even autoracks won't fit. (the first time you through in the head end, you can't help but wonder how your locomotive is going to get in...)

I understand that they can't simply lower the floor because of some sort of structural reinforcements beneath the roadbed. This means that the tunnel will have to be crowned -- a difficult, dangerous and very expensive operation. I'm thinking several feet or a meter or two.

How long would this take? Shut down the sub while doing the tunnel or use windows? I should think shutdown...

Is redoing the existing tunnel really the best and most effective way in the long run, or is an oft talked about entirely new bore better? It would be longer, certainly and at a lower elevation. A new bore would eliminate much of the grade and curvature between Easton and Lester, certainly. I can't help but wonder if it might be a lot simpler, too. The existing tunnel could be used until the new tunnel is ready. But again, an expensive proposition. I'm certain that somewhere in the BNSF engineering department, there are studies, etc. NP considered it...

Wild cards, at least to me, are UP and economic stimulus -- many construction jobs either way. Now is when it makes sense to do it --traffic is down, but it will most assuredly pick up and grow again. I should think it best to be ready.

My gut feeling is that I'll believe whatever they do when I see the equipment arrive. Oh, and bean counters take note: when it comes to railroading, the cheapest way is rarely, if ever, the right way.

[Damon Hill]

Could always reopen the MILW over Snoqualmie Pass; those tunnels had plenty of clearance. This would give a route for double-stack and other clearance-challenged loads. It'd require a few miles of new track to connect to the former NP line; I don't think Renton would be happy having a mainline operation reopen in their midst.

But that's just the musings of a MILW fan....

If traffic warrants the investment, a new tunnel will be bored. Good question about the engineering involved in modifying the Stampede Pass tunnel; water drainage is a big issue and it has to flow somewhere without soaking the ballast and track.

[SDP40 322]

Well, we all know its the Cascade Tunnel ventilation that is creating the bottleneck that causes the delays, which limits the number of trains. Some years back, I remember hearing about some other options, other than cutting Stampede. One of which was re-electrification of the line, but I doubt this will ever happen. Yes it can increase the traffic through the tunnel, but it would create other delays when having to change out motive power at Skykomish and Wenatchee. Also, getting the needed infrastructure installed would be extremely expensive, not to mention new maintenance facilities for electrically operated equipment.

The other option is to revamp the Cascade Tunnel ventilation system into a multi-zoned system. If I remember right, there are other very long tunnels that use a multi-zone system that basically isolates sections of the tunnel for much faster ventilation. Plus, since the Pioneer Tunnel is bored 5 miles into the mountain, it could act as a means to ventilate exhaust. A multi-zoned system would also be very expensive, but probably much more cost effective than other methods of increasing Cascade Tunnel traffic. However, it does not solve the problem of having more than one path through the mountains. If something were to happen, and the line be out of operation for weeks, it would cause major problems everywhere else.

Snoqualmie Pass will never be reopened to rail traffic, even though it was probably the best route. It had the lowest elevation with the smallest grades in either direction.

Ideally, we need two passes that can accommodate the same type of traffic, with the same frequency.

Side note, how is the Stampede Tunnel ventilated?

[redlynx]

Right now, it isn't. NP had giant blowers on the west portal. I suspect that the suction created by a train helps. The tunnel is about 10,000 feet long, vs. some 36,000 feet for the Cascade tunnel. One other note: When Nelson Bennett bored the tunnel for NP back in 1888, it was done on the cheap, as required by the beancounters -- hence the small size. NP, and now BNSF pay the price of saving a dime, even 125 years later!

[SDP40 322]

I think your meaurements are a little off. I know the Cascade Tunnel is over 41,000' long. Not sure about the Stampede Tunnel, I though it was over two miles?

[Trackside]

From what I understand the floor would be dropped instead of cutting the ceiling.

One of the other design flaws to consider is that the highest point inside the tunnel is in the middle. So there is a slight grade, until the middle, then the grade drops off a little. That's why you can't look into the bore and see the other side. So from what I understand a lot of the hot exhaust gets trapped in the middle.

[redlynx]

Originally Posted by SDP40 322

I think your meaurements are a little off. I know the Cascade Tunnel is over 41,000' long. Not sure about the Stampede Tunnel, I though it was over two miles?

You're right about the Cascade tunnel. Stampede is a little over 10,000.

Rosco is right, the summit is in the middle of the tunnel; in the steam days it was sometimes called "Stampede Hell."

I've been told that because of massive concrete braces under the floor, dropping the floor is not an option. Apparently these were installed in the 40s or 50s and are preventing collapse. Of course, this may not be the actual case.

[Trackside]

From what I understand the tunnel walls/ceiling are brick and mortar. I wonder if there is any rebar in it and what condition its in. Either way this is going to be a big money project which is of course why it has never happened.

[redlynx]

Brick and mortar it is, overlain with gunnite or some sort of cement; inside, it looks just like the Cascade tunnel does. Rebar unlikely -- a brick arch is strong. Somehwere I read that the bricks are actually Chinese, brought over as ballast (no, not rr ballast, but ships' ballast, so transport across the Pacific was essentially free). Even then, money could be saved by importing from China! At any rate, the mortar isn't all that good after all these years, moisture, earthquakes and vibration from trains. The tunnel work they did when the line was reopened somewhat alleviated this problem.

[Trackside]

Chinese ship ballast is correct from my understanding as well for Stampede. I was under the impression that the Cascade tunnel is concrete and rebar which is a much stronger design. The other thing about the Cascade tunnel is that it required far less work to fit double stacks since it was already high for the catenary wires.