Could this Idea Keep Big Savage Open All Year?

If anyone has traveled the Montour Trail (a 48 mile suburban rail-trail in southwest Pittsburgh), you will travel through the 660 foot National tunnel around Mile 25.
When travelling through, riders will get a few drops of water on them as the ground water seeps through the cracks in the spine of the tunnel and it continues 365 days a year. In winter, this water is a big issue because when freezing temperatures enter the tunnel, the water freezes and forms columns of ice that seem to get bigger and bigger as the winter progresses. There is no easy way to pass through unless you had ice crampons!
This was a major safety risk to the Montour Trail Council. They would put up orange signs warning people to not enter but inevitably some would try to pass through and climb over the ice. This same ice would not melt until April or May leaving this part of the trail unusable 4-5 months out of the year.
As an experiment, they completely boarded up the two tunnel entrances with plywood last year (winter 2015/16), closing the tunnel for almost 4 months. The thought was that by closing off the air flow, the tunnel should stay warm enough inside so ice cannot form. The experiment was a success as temperatures stayed a consistent 48 degrees all winter and no ice built up. This allowed them to open the tunnel much earlier than normal.
This winter (2016/17) they are trying a slightly different experiment. The same wood walls are going up but with a cut-out you can walk through (looks like an 8’x10’ cutout). The cut-out openings are covered with two sets of see-through plastic curtain strips similar to entrances to cold rooms. There is no door just these plastic heavy plastic strips that you push aside and pass through. Push through the first set of strips, then pass through a second set of strips a few feet later.
This does two things: Allows safe passage through the tunnel year round while keeping the temps above freezing, not allowing ice to form. They are calling it an “air lock”.
I could totally see this working for the Big Savage Tunnel. No more closure date announcements and no more wondering where the detour is. Surely this could work, couldn’t it?

Very interesting idea. Certainly seems worth considering/trying.

If this is possible/feasible I would definitely be up for a winter trip on my Fat Bike. I know the weather stayed fairly mild till later in the year so this could be a good idea.

Has anyone travelled up to the closed tunnel doors in winter? Is the reason for it's closure more about high elevation snow accumulation approaching the two entrances and not so much about ice build up inside the tunnel like the Montour Trail? I don't recall too much water seepage in Big Savage so I can't say for sure. Or maybe it is. Is it really dangerous to travel up there in winter (as in you'd need snow shoes to make it through)? Has anyone ever heard exactly WHY they close it for winter?

From the GAP web page on the Big Savage Tunnel closure: "The tunnel is closed between roughly December 15 and April 10 each winter to protect it from icing damage."

I suspect there is ground water leakage inside the tunnel and when the cold
temps come through, the ice begins to build up. No reason the same idea for the Montour Trail National Tunnel couldn't be applied here. My hope is that the people who run the GAP organization could stop at this tunnel on the Montour Trail in winter to see how this works with their own eyes and see if it's feasible at Big Savage.

bears and other animals would den up in the tunnel

Interesting. Hadn't thought of animals getting in there. Certainly bears are not a major issue in suburban Pittsburgh for them to consider. Has there ever been a bear sighting in the tunnel when it's open the rest of the year?

Risk (of Tunnel Damage) vs Gain (of more cold weather bikers). Given the millions spent to renovate the tunnel, it would take a very strong and researched argument to change the closing dates or closing process.

There are a couple of other factors to consider as well: 1) Big Savage is a Mountain, and there is a considerable amount of snow that accumulates on the mountain; 2) I don't know what the surface of the Montour Trail is like, but the GAP surface is crushed limestone, and in the early Spring, the local riders ask for people to stay off the GAP until the surface is sufficiently thawed and dry to avoid tracks.

I will never forget the first time I met Harry Beal,an ex-Navey Seal and trail ambassador at the west side of the tunnel, he said "see any bear" I replied "no" he said "said they see you."