So, actually, a harbor RR tunnel WAS studied in 1994
https://drive.google.com/file/d/1SfOmrQ-DMgM94NRvv3MtVTR0mV5vHOX2/view?usp=drivesdk
-unnecessary snark-
Back to the study. They were assuming sunk tubes, ala Ted, at $420M. The route they were suggesting at the time was about 2x the straight shot to Eastie.
The distance from the present Transitway to the shore of Logan is 1.2 miles. Assume 1000ft of incline to get you above ground.
The distance from SSU to Airport Station is 1.7, so yes, .3 mile longer. However, even with a transfer at Airport, for many, one less transfer.
Alright, so let's take your costs from this '94 study, and correct for inflation (which is closer to 75%, not 50%), and also include the costs to get from SS to the harbor tunnel, and from the tunnel to Airport Station, Airport Station itself, and Airport Station to the existing ROW (since the all-in matters and you've gotta do all of that, the tunnel doesn't exist in a vacuum). That's $675M in 1994 dollars, or $1.2B today, omitting right-of-way, vents and exits, tracks, signals, electrification, environmental remediation, engineering and
slushfund I mean, management and contingencies. The study observes that the latter three typically are allotted an additional 20-25% in budget ($220-275M). The study also observes that vents and exits for the Logan tunnel were expected to cost at least $80M over the CA/T alignment, for a total of $170M. That includes the Chelsea Creek tunnel, which we wouldn't be using, so cut it in half (although the Harbor crossing almost certainly was a bigger share of cost than Chelsea Creek). $85M, translated to 2020 dollars gets you $150M. Due to lack of information in the study, I've omitted any right-of-way costs in Eastie, track, signal, electrification, and environmental remediation costs.
These costs will exist, I'm just not a civil engineer so any estimate I make would be a shot in the dark.
So our price tag is a floor of $1.7B for the cross-harbor tunnel. Again, we know it will be more than that ultimately, but let's stick with that. BLX + Son of Ted, in comparison, are between $1.8B and $2B all-in depending on the exact assumptions made. That's not a large difference, and due to several of the assumptions I made the floor is probably a little bit higher for the cross-harbor, and a little bit lower for BLX and 3rd Ted.
I never meant to imply that BLX and a Ted bore were in competition. I didnt start the cost comparision.
Understood.
Also, the Logan study provides a potential rough cost of a Ted tunnel by tubes.
I don't see why we should base our costs of a Ted bore off of a Draft Study from 1994 when we have the actual, real-world, cost of the Ted tunnels that have already been built. I'd be interested in the estimates from a 2020 study, however.
Lastly, I think that anyone who believes one piece of predictive data that the MBTA puts forth probably believes in Santa. Their continued efforts to sandbag are legendary. The E/W Passenger Rail Study is just the latest.
The Harvard study is a more reliable one, in my opinion.
I'm happy to evaluate the options based on whatever dataset you choose, as long as it's consistent. The T sandbags all the time, but it's at least an expected sandbagging. I'll compare T to T, or Harvard to Harvard, or we can agree on a reasonable reduction factor to reduce the T figures to something we can compare to Harvard's study. But bear in mind that it makes the existing CA/T and BLX proposals cheaper if we assume that the T is sandbagging everything.
So, the question becomes tubes or TBM? So, where do you balance cost inflation vs the 50% smaller scope? If one wipes out the other, $420M. If inflation is 50% more, then $630M. Combine that with either one large or two 20ft bores the .6 miles to Airport.
Combination done above, with proper inflation factor applied. I only factored in the costs as listed under the "Logan Airport to South Station" header, anything north of the Airport was omitted.
Or, if it can be done cheaper, TBM under the harbor.
No data to support that TBM would be cheaper. So sticking with the data you've presented.
There is no data that I've seen, either here or elsewhere, that predicts higher costs for a harbor 2nd tunnel. The closest is comparing the Congress vs CA/T 2 track alignment costs. But even that is not apples to apples.
Of that, you are correct (primarily because I based this off the originally presented graphic). However, several of your assumptions are incomplete at best, as I've illustrated above.
I am sorry if I have been unclear.
Two track NSRL has a limit of 24 tph. This would be insufficient for the present number of Southside trains and for the expected expansion of Northside trains under Regional Rail. Thus four track NSRL.
The question should be "is the best placement of the second tunnel directly next to the first?". How much additional benefit that a different routing might give us vs what we might give up.
Who suffers with a harbor routing? Several North-South pairings have been offered, but one popular one is Worcester-ER. So, Worces.terites who wish access to the northern CBD would continue to switch to OL at BB instead of the potential one seat.
Considering the fact that WOR-NS access via the GJ comes up fairly regularly, it's a fair bet that WOR would rather one-seat access to NS than the Airport. It also would mean that NSEWRL would not be easing the downtown crush-loads at all by keeping WOR riders making that transfer at BB as they currently do.
As there is a slight imbalance, perhaps as many as four other trains would lose that access as well, either split up between the other lines or, say Franklin. So, Franklinites also would need to do a same platform transfer with a 4.5 min wait if they desire to go to the northern CBD. Eastern Routers would also lose one seat to the northern CBD. Everyone else still has their one seat to both SSU and NS/CSU.
So what is the tradeoff? Much quicker(3 fewer stops, 3 mile shorter route, straight route)ride to SS, BB and SP for the nearly 40% of present Northside riders who take the ER. Probably 8 min minimum. I would even argue that most ER riders who would change at Airport would find that the maximum 5 min delay Easier access to jobs at Logan, a major employer, especially for Lynn residents(yes BLX would provide access as well, albeit slower) and ER/Worcester and Franklin Line riders.
And yes, easier access to flights for most people in Massachusetts without the expense of a Ted SL of GL tunnel.
SL1 already exists. It gives direct terminal access. You're solving a problem that largely doesn't exist, at least from the southside.
However unmentioned so far is the fate of Chelsea, Everett and Southern Revere in this brave new world. To me, this is the icing on the cake. The present RR track from Winthrop Ave to Sullivan Sq can be repurposed to either OL or GL.
I'll look later, but I've definitely seen long-range GL extensions proposed on this very forum to Chelsea and possibly Logan without needing to displace the current CR.
Leaving Malden Center on a branchline isn't exactly ideal either if you want to shoot Orange out there, but F-Line can address that better than I can).
OL would be easier to connect with the Mystic bridge than GL. It would also offer an option for ER pax to access Haymarket.
Considering how close NS and Haymarket are, ER riders already have that access functionally. Just walk, or take one of the distended Lynn buses that will still be making the run all the way to Haymarket given that the Lynn routes will still be screwy. Not everyone needs a one-seat to every single CBD station.
And, yes, I know that many of you will jump about how freight to Chelsea will just explode any day now, but one train, temporally separated and using a gauntlet track over the bridge, should be more than sufficient for any expansion. And before everyone starts clutching their pearls and sputtering about CSX never giving up rights to that oh so lucrative bone train to Peabody or their GJ rights, I would argue that those AND a reasonable attitude about E/W Rail(never mind hopes of money for Hoosic Tunnel and Worcester-Ayer upgrades) would be a price that CSX would gladly pay for state support of the PAR acquisition, nevermind the thanks of three of the most powerful congresspeople around.
And yes, even an hourly direct train to Airport from whatever other southside lines dont run there more frequently, would be a desired, well used service. And northside riders can make a cross platform transfer for the 5 min frequency to to Airport, where the people mover(the utility of which is increased by addition of the ER) brings them to their terminal( or they take the much quicker bus from there rather than the SL) It also makes GL Transitway conversion a much easier project.
Also, this routing is easy(assuming provision is made in SSU) to do incrementally. You can do two track CA/T or Congress first and then harbor tunnel/RT Chelsea later. It might mean sunk tubes vs TBM but probably not the end of the world.
You
can make this work, but my contention is that there are easier, cheaper, and universally more productive ways to make these improvements. And I don't appear to be alone on that stance.
