Why would a railroad daylight a tunnel? Are tunnels high maintenance? Maybe for added clearance…Tunnels offer natural protection…from rock and snow avalanches…no?
…I would say you hit on at least 2 of the reasons…Clearances {some cases}, and on going maintenance costs. I certainly would think RR’s would be happy to not have any to contend with, if possible.
More than a few tunnels were converted to open cuts after earthquake-induced collapse, since the ground was too unstable to re-tunnel and loose enough to be readily removable with modern earthmoving equipment.
A lot of very early tunnels, dug with hand tools, wheelbarrows and black powder, were made just barely large enough to clear the locomotives and rolling stock of the day. If the same track was built today, using present day explosive techniques, power shovels and haul trucks, many of those tunnels would have been open cuts from the beginning.
One of the major considerations about daylighting a tunnel is the nature of the covering material and the shape of the ground. The former NYC tunnels on the east bank of the Hudson River above Poughkeepsie would never be daylighted, since the rock is armor-grade granite and the ridges are very tall and thin.
The tunnels at Gallitzin, at the summit of the grade that includes Horseshoe Curve, were opened up to accept modern loads but not daylighted - they are a little too deep underground and the surface above is covered with houses…
Chuck
In the old days of steam it was the coal gas that would kill you. Tunnels possed huge problems with long trains and slow working teams of mallets. Some RR’s issued gas masks for the crew before they entered long tunnels but how would see what your doing?. I have read stories on NP RR on Mullan Pass that the fireman and engineer would pass out and the train would free role back to Helena unless the brakeman or conductor could stop the train, this prompted the NPRR to install a very expensive ventilation unit that is still used today on the Montana Rail Link.
Also Locomotives and Cars became bigger and taller. Most tunnels did not have the clearence for these, so over time RR’s would enlarge the bore or ‘daylight’ them based on the cost.
…A parallel example might be over on the Pennsylvania Turnpike. Originally opened {Oct. 1940}, with 7 {2 lane}, tunnels, {all started as railroad tunnels except one}. In later years when the 2 lane bottle necks formed from increased traffic some were supplimented with a 2nd parallel bore and some were eliminated completely where possible. Bypassed without increasing grade {max 3%}, but some could not be because of other reasons. Some had excessive cover to daylight.
Believe there are 3 tunnels remaining {double bores now}, on the original 160 mi. opened in 1940. It seems road builders and RR’s construction would rather do without tunnels where possible. They are an expense to keep in a safe and updated condition.
Tunnels were one of the reasons SP converted a group of engines to cab forwards to keep the crew from being gassed as several were killed. I was under the impression that the “Gas masks” were really hooked to the air resevoir and supplied breathable air from the air tank(s). The real reason a tunnel is daylighted is that it is the cheapest solution to one of the problems previously metioned.
The Burlington Northern did a line relocation on Crawford Hill In western Nebraska about 20 years ago… They moved the main line away from Belmond Tunnel and the left the tunnel to the state of Nebraska , They in turn made it part of a biking and hiking trail . The tunnel is still there and is used nearly every day Larry
The CGW would have loved to rid itself from the Winston tunnel in northwest Illinois. That tunnel was constantly in need of repair and was a HUGE financial burden for the road plus it had a low clearance which may have been part of the reason why potential merger partners the CGW was seeking to merge with back in the 50’s and 60’s were not serious about merging.
Jeff
- Very expensive maintenance of any tunnel through incompetent material, with ground water flows, or through material affected by presence of oxygen.
- Extremely expensive to maintain track through a tunnel.
- Drainage of track in a tunnel is almost always a problem. In the winter the water freezes, and ice removal is very expensive and hazardous.
- Clearance envelope may be too small for current equipment standards.
- Liability and risk are very high; tunnels have a tendency to collapse, tunnel linings to burn, and trespassers to enter.
- Snow issues – snow is pushed into tunnel by trains or snowplows where it forms ice, which retains water, degrades track and lining, and if it builds up has to be melted out or chipped out by hand to prevent trains from derailing.
- Very hard to clean up a derailment in a tunnel.
- Exhaust gas clearance issues in long tunnels.
- Fire hazards of equipment in tunnels; requirement for escape and egress of personnel and passengers as trains can catch fire, and in a tunnel is a very bad place to have this happen.
- Communications disruption of regular VHF radio, distributed power, communications-based train-control.
- Difficulty and expense of maintaining power and communications transmission lines through tunnel.
- Difficulty and expense of maintaining wayside signal system track circuits in tunnels – the variabilitity in moisture in a tunnel leads to shunting problems leads to numerous signal system failures leads to numerous train delays leads to recrews, poor equipment cycle times, etc.
- Access roads for railroad maintenance use are discontinuous (99.9% of the time) at tunnels, or must go around tunnel, if possible.
The reasons given are all good.
During the mid-1980s, I spent quite a bit of time on the old WP enlarging tunnels for the first stack trains. Whenever possible, we daylighted tunnel ends because the sky above is easier to maintain than dirt above. Clearance is certainly an issue, but unless the hill is solid, a great deal of expense is involved with lining a tunnel and keeping it stable.
Even if the tunnel is cemented, that doesn’t guarantee that it is stable. I also worked on the Altamont tunnels just east of Evanston (WY) and those tunnels moved all the time. We would routinely measure how much the walls moved inward and remove material to keep the tunnels open.
Basically, a tunnel is a pain.
Bart Jennings
Railway Man’s #7 reason, “Very hard to clean up a derailment in a tunnel.” is quite true.
Back in '89, my wife and I were going from Los Angeles to Seattle, and everything went well until after we left Klamath Falls. We were in the diner, eating breakfast, and we stopped by Upper Klamath Lake. I did not think that we stopped so that we could enjoy the view of the lake–and I was right; we soon backed to Klamath Falls, so that passengers could send messages, at Amtrak’s expense, to let people know that the train would be late because a freight train had been derailed in one of the tunnels. After some time, we moved up to Chemult, where the dining car steward replenished his supply of food, and we waited some more. Our next wait was at a pass track well north of Chemult, where we waited until the line was clear. Once we were under way, we ate dinner in the diner (nothing could be finer, not even ham and eggs in Carolina); the conductor came through (he removed his cap as was proper in the old days because he was not lifting transportation), and I asked him if he were going to be outlawed. He told me that he already was outlawed (it was more than twelve hours since he had gone on duty), but there was no way to get any relief to the operating crew until we met the westbound passenger train. We arrived in Seattle ten hours late, having spent two nights instead of one on the Coast Starlight.
On the NS “Pokey” (ex-N&W main line) in West Virginia, daylighting some tunnels made more sense than trying to raise the height for double-stack trains, while others had their height raised but remained tunnels.
In West Virginia, too, there is no West Virginia Turnpike tunnel any more. It’s been gone for years. For a couple of years after it was closed (and fenced off) there was a giant American flag there. Now the ex-tunnel has more or less reverted to nature and can’t easily be seen from the turnpike itself, which has a gentle swerve around where the tunnel used to be. Construction people simply removed a hill which was just to the north of the W.Va. Turnpike tunnel.
…Now that seems a bit strange…Wasn’t that route constructed in “modern” times…Seems strange they didn’t do that in it’s initial location.
Well . . . modern isn’t all that modern. The turnpike was built in the Fifties when construction and earth-moving equipment wasn’t nearly as huge and sophisticated now (think of PRB). The improved technology has also “daylighted” many underground mines, turning them into strip mines. Runoff is bad for the environment, also particulate matter rises, but MUCH safer for the miners themselves.
A tunnel problem that can’t be solved by daylighting:
I saw a TV show on the historical geography of Manhattan Island. It seems that so much landfill has been dumped in the Hudson on both sides since colonial times that the river has been narrowed significantly. The water flow has not changed so the speed with which it goes past Manhattan has increased. Scouring is causing the river to become deeper and there is a definite danger that this will uncover the tubes of the Lincoln, Holland, and various RR tunnels, threatening them with failure.
By the way, my father’s stepfather, Joshua Paxson, was the Chief Engineer on the construction of the tunnel sections of the PA Turnpike.
Jack
That must have been an early build of the interstate system as I believe that started in '56. Then, maybe that turnpike predated the interstate and was integrated into the system when it came along.
Many major projects were accomplished back in the 50’s…Pretty good equipment even then.
7 miles of US highway 30 was totally relocated past my small home town in Pennsylvania…Started back in '37 and opened in '38, and it was rough territory to get thru and the "cats’s and “scoops” and power shovels, “dozers” and rooters {to unseat massive rocks}, etc…and lots of dynamite made it happen. Did so in pretty good time too.
…That’s pretty wild Jack. I assume you are well aware then of all those tunnels {except one}, were originally started for the SouthPenn RR and was never completed and the R of W lay dormant for roughly 50 years before the Pennsylvania Turnpike Commission was born, and created the Pa. Turnpike. Original portion opening in 1940.
There aren’t many places in the south that have toll roads, but the WVa. Tpk. was and is one. As originally constructed, it had no Interstate route number – but it had and has signs with their logo (and “TO” signs with the logo on connecting routes). Also the most mountainous (and least traveled part) originally had three lanes, generally two going uphill and one downhille. My father drove it in the mid-fifties I don’t know if it was in 1956 that it was worked into the plans for I-77, but Virginia to the south didn’t finish all of its I-77 link to North Carolina until the early seventies FWIW. Rumor has it the Rockefellers profit from ithe West Virginia Turnpike and always have, but I don’t know. I do know that it stayed a toll road by upgrading itself, going four-lane, and today it has some goodies “ordinary” Interstates don’t have – lit-up speed-limit signs that can change mph according to terrain or weather, for example. I for one like the rest areas with their “rockhound” collection of small esoteric stones for cheap. And overpriced Exxon gasoline. Hmmm [#dots]
BTW Kentucky used to have a sizeable number of toll roads but (glorisoky!) they paid for themselves and went free of charge as promised. There are no more than one of two of them that remain toll roads, perhaps not even that. I myself contributed my fair share of quarters to the “Mountain Parkway”, now called the “Bert Combs Mountain Parkway.”
You might remember or have heard that the Chicago Skyway (which now is mostly at ground level) originally ran just to Stony Island Boulevard, which is now the second-busiest interchange other than I-94. The Skyway was completed in 1953, which of couse predates the Interstate era. Sorry I’m getting way OT but wanted to offer a comparison and an analogy. - a.s.
BTW wasn’t there an old abandoned RR tunnel or two that was us
…Al: See my posts earlier on Oct. 17th and 18th,…I address some of that. It happens to be a keen interest of mine over the years…My home was very close to it. Rode on it the first week it was opened and in a section that had the Laurel Hill Tunnel {about a mile in length}, and that was in Oct. 1940. That tunnel was abandoned decades ago and by passed. Extreme amounts of earth required to be removed to go around and bypass it. The tunnel is still there and all the tunnels have like a cult following of interest…
On daylighting…The recent rework at Cajon area included 2 tunnels that were daylighted. So the gains {less maintenance expenses}, must outway the cost of daylighting them, plus perhaps a clearance value.