December 15, 2007
Tunnel envisioning

Looks like Gonzalo Camacho and his I-45 tunnel concept have gained themselves a convert in Tory Gattis.

A few weeks back, Gonzalo Camacho sent me an intimidating 30-page white paper (PDF) on the tunnel option for expanding the I-45N corridor using some of the newest tunnel-boring technologies from Europe and elsewhere. It took me a while to get around to reading it, but in one fell swoop it converted me from skeptic to a true believer.

The essence of what makes it so compelling is that all of the money spent is for completely new capacity, since the existing surface 45 stays right where it is. Compare that to the current alternative being proposed, which, at the end of the day after $2+ billion is spent, only adds a net of 3 new lanes of capacity between downtown and Beltway 8 (from 8 + HOV to 8 + 4 managed lanes) - and that's after 5+ years of nightmare construction (vs. disruption-free underground tunneling).

On top of that, the tunnel can also solve several problems not addressed in the current plans, by continuing through downtown to 45S, 288, and 59 - bypassing the downtown bottlenecks at the Pierce Elevated and the 59-288 junction. Talk about killing several birds with one stone.

What we're talking about here is a congestion-priced, tolled set of express through-lanes that only have a few exits at major junctions. Local traffic stays on the surface freeway, which may evolve into a more sedate parkway over time, like Memorial or Allen Parkway (although I'm more skeptical of that ever happening - given the high demand and powerful commercial interests along that freeway).

That point about all new capacity is something I hadn't considered, and I agree that it changes the lane-mile cost comparison when you think about it in those terms. You'd still have to deal with things like the 59/288 junction in this scenario, but since you don't have the constraint of an un-widenable elevated freeway at that point, you can design that interchange in a way that won't be a 24/7 bottleneck. It really does solve a lot of problems all at once.

Tory adds some suggestions and enhancements in a followup post. I've been skeptical of the idea that this thing is sellable to the folks who make the decisions about stuff like this, but pretty much everyone that talks to Camacho comes away liking his plan, so who knows? Maybe for once the big dream will come true.

Posted by Charles Kuffner on December 15, 2007 to Planes, Trains, and Automobiles