Thanks for the photos Swoosh. I have a feeling the stake is someone messing around, lol.
Just curious, but why would you assume that putting a tunnel under the roadway would not be cost effective and cost more than the ride itself? It's just a four lane road. Assuming there are no utilities to contend with, I would think it's as simple as closing the road one lane at a time, digging to the depth you want the tunnel and burying pre-formed hollow concrete "blocks". When one or two sections are laid, you backfill over them, slap down a new section of pavement and continue moving until you've reached the other side. The county I live in has done this dozens of times as hundreds of miles of old railroad tracks have been converted into a massive network of bike trails. I can't imagine something like this (if they are in fact doing it) being much more than a larger scale version of the same thing. We aren't talking about a million dollars to put a tunnel under 40-60 linear feet of asphalt.
A lot of construction sounds easy, but when you deal with major roadways the costs can easily become astronomical. I don't do cost estimating in my area of work at all, so I have no real idea, but from similar projects I've seen involving overpasses and the like, a few million would be cheap for that kind of tunnel. A lot of it goes beyond just basic construction with all the planning, traffic control, permitting, etc. that has to be done in relation to it. SDC has a major advantage in that this particular roadway doesn't get as much use during the off-season, but the costs are still way more than what should be worth it given all the land they have inside the park.
B&M has built coasters over roadways though (Goliath at SFOG), so a B&M going over the road isn't out of the question.
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