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Old 11-22-2013, 02:11 PM   #1561
F-Line to Dudley
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Re: Crazy Transit Pitches

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Anyone aware if the design of new Harvard station precludes reopening the Eliot yard tracks? Turning either the new mass ave branch or the braintree branch at harvard would solve these issues (and it could later be extended to Allston). With the massive scope of this project, partially rebuilding harvard wouldn't be out of scope. Central would likely have to be rebuilt as a dual island station as well, if possible. Even with the existing configuration though, while there would be excess trains central-north, it doesn't mean they have to cut trips downtown. When it comes down to it the designers of the rl north extension really shot themselves in the foot not installing more frequent crossovers in general, and a pocket track after harvard. Having to run everything to alewife is a huge flaw.

And just to reiterate, a mass ave branch would siphon off a decent amount of existing RL traffic, which needs to be taken into account when weighing headways. So even if you do have to reduce the downtown headways by a train or two, the traffic might not even be there. I'm too lazy to find the numbers and am just doing this seat of pants, but it would be intresting to see just how many people are getting off the red line at park/dtx/south station and taking a train/bus east. That, plus the ridership of the 1 is the potential traffic for this branch. I have a feeling its a significant number.
Tracks were switched from the Eliot side to the Alewife extension in a single weekend, so technically no train movements are prevented from a split that way. But the lack of space to tie a whole parallel set of 6-car Red Line platforms into the station renders it totally moot. You'd have to blow up buildings in the Square to finagle that, and construct egresses into the station from a tunnel that was never designed for that. Plus the curve is truly a wretched place to put a junction. It's a bad enough crawl into the new station to have a tight pinch. It would get even slower as a derailment prevention necessity (much moreso on the Alewife side, but the Eliot side would be sluggish too) if you threw down a switch right at the start of that curve from hell.

The only thing that tunnel could feasibly be used for--and we don't even know this for sure--is an LRT stub terminal off the Urban Ring from Allston. You might be able to coherently fit a 4-car LRV platform with a track grade crossing to a hole punched in the wall to the fare lobby within the space of the 3-track portion of the tunnel. You almost certainly can't do that with 6-car RL trains or fitting a grade-separated egress that doesn't have to disruptively bust outside the existing tunnel structure. But...caveat...we don't even know if that much is possible. Plan B on a cross-Charles LRT line may well have to be putting rails back in the bus tunnel pavement and going back to the 1950's when streetcars, TT's, and diesel buses all co-mingled in the same space.



Branching anywhere to the north just doesn't work the way the RL is set up. Be it a Main St. split to the south, a Harvard split, or an Alewife split to Waltham or Lexington. Cabot Yard only points south from JFK, so there's a very big problem of how you're going to supply enough northbound vehicles when all revenue service through downtown still has to be tethered off the small storage yards at Braintree and Ashmont and the Ashmont + Braintree schedules running the full length north. Any way you slice it there's a capacity cap here that starts harming the works when it has to feed equivalent headways on all northern branches. It's physically impossible to turn the spigot out of Cabot to the north to bootstrap it. JFK isn't configured to reverse direction into downtown service or pull a short-turn out of service something like 1 out of every 3 rush-hour trains that it would take to adequately supply these branches.

That starts creating imbalances. So if, for example, you had branches forking off Harvard trans-Allston or Alewife to Lexington and Waltham. Each branch can have its own storage yard (for Waltham it can even be at Alewife-proper, but pointed in the wrong direction for Lexington to use). So there's no shortage of how many southbound vehicles you can send. But northbound can't keep up because they have to run the full 26 miles from Braintree or 20+ from Ashmont and JFK turns can't non-disruptively make up the difference.

Or...say there's the Mass Ave. subway. The only place that can have a yard is in South Bay outside the subway. Possibly even looping around from Cabot. You can feed that one as full as you want. But it puts the single biggest-ridership chunk of the entire MBTA system--Andrew thru Kendall--in a bind. Harvard curve is still a limiter to capacity to the north. The T estimates today that CBTC signaling can establish best-case 2-3 minute headways throughout the JFK-Alewife stretch. Maybe a little worse, but still a healthy improvement over today. Harvard curve is still going to be the ruling bottleneck for the max possible service density on legacy infrastructure. Therefore feeding Central and Harvard with another fork out of downtown can't really increase service density beyond the best-case they envision with a CBTC installation (which...remember...could happen as early as decade's end if they chose to fund it, and could still fall below that 2-minute best-case when actual engineering is done). What has to pay the price to support this: Kendall-Andrew and the 4 (w/Red-Blue) consecutive transfer stops. Maybe 5 consecutive if Broadway gets an Urban Ring routing. Either both subway flanks have to load-balance to the Cambridge merge at something a little worse than today's headways on each, or making Mass Ave. have useful headways means it has to get 100% of the extra headways above today and downtown gets capped at status quo forever. Keep in mind downtown does not stop growing. Orange and Blue feeding the DTX and Charles transfers become capable of the same 2-3 minute headways under CBTC. So "status quo" Red gets a ton more transfers dumped onto it by the headways-on-steroids Blue and Orange will get. Plus a completed Seaport-Back Bay connection and ever-expanding southside commuter + intercity rail keep shoving more load onto SS.

Maybe the Mass Ave. subway blunts the crush of 50-year RL growth considerably and establishes an ultimate equilibrium, but you are still looking at growth towardss more total RL riders at the downtown stops than today. And the Red Line there becomes structurally incapable of tapping the necessary headways to track with this 50-year downtown growth because all that service density got diverted out to Cambridge. Welcome to more-harm-than-good territory. Saving the Red Line in Cambridge ends up breaking the Red Line downtown.

Given the billions that bypass alone costs, the only way around this is spending billions more nuking the downtown RL for a different configuration entirely and tackling the same godawful engineering issues in even greater density. And like another couple billion to nuke Harvard station in its entirety--including the bus tunnel--for an even lower-level rebuild that can pass underneath Harvard Yard on a gentler curve that lifts the capacity cap. Rebuilding the entire works once more with god knows what else in mitigation.



Do you guys see where nihilistic pursuit of pretty lines on a map starts exponentially harming itself the harder that boulder gets pushed uphill out of spite for the size of the boulder?
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Old 11-22-2013, 02:16 PM   #1562
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Re: Crazy Transit Pitches

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Nope. It's shallow cut-and-cover tunneling for the first half-mile out of Harvard. There's a regular below-street emergency exit at the corner of Chauncey St. that puffs out a loud blast of subway air with each passing train as you're waiting for the walk signal to cross the street to the new Lesley U. building. And you can solidly feel the rumble beneath your feet as far north as the Shepard/Wendell intersection, further if you've got keen senses. Remaining distance to just shy of Porter Exchange Mall is the transition zone from shallow to deep, but at such a gradual descent that most of the construction was still done as ever-deepening hole in the road until they were almost at Porter. That bedrock seam starts at roughly the same latitude as the northern tip of Fresh Pond. They weren't TBM'ing through real surface-supporting terra firma until past Linnaean St.

This is the widest portion of Mass Ave. in town--75' curb-to-curb--and in 1980 was mostly a drab stretch of 1-2 story storefronts with occasional 4-5 story brick apartments. Road's only 60' wide from Main St. to the River and 55'-58' wide on the Boston side, and has 6-story or greater abutting structures on nearly all of that stretch. It'll also require it's own transition zone deep dig on both sides to get under the Charles, so that's a very deep gash in the road in the places where the construction causes maximum disruption and where the soil is at its siltiest. See where this starts getting entangled in itself?



Water tunnel ≠ double-bore transit tunnel. Not in size. Not in weight distribution. Not in utilities carried. But why don't you go explain to Parsons Brinkerhoff why all tunnels are exactly the same. I'm sure they'll say, "D'oh! Why didn't we build the Big Dig that way?!?"

Right. Because every public piece of civil engineering is designed and built totally in-house by nuthin' but state employees wearing mining hats. And nobody like Parsons Brinkerhoff with actual engineering expertise and experience subcontracting gets allowed to touch it. Because that's how state gov't really works!

Nope, bud. You're on the same nonsensical spleen-venting ˇUNIMAGININATIVE POLS! rant you were on last page. Calm down for a sec and think how the real world works before trying to pass this off as your argument.
F-line, I don't want to have a pissing contest about this.

I understand that a water storage tunnel is not equal to a double bore transit tunnel. The transit tunnel is much more complex.

All I am trying to suggest is that the default position, in Boston, is always cut and cover tunneling. But there are definitely examples from other dense urban areas where deep bore tunneling can be competitive in terms of total construction cost, and come out ahead in terms of economic benefits. Cut and cover causes a lot of economic dislocation to the surface right-of-way above the cut, and this is rarely factored into the official project costs.

And I get burned when people suggest that a technique cannot be done technically (deep bore tunneling in clay and gravel fill), when it clearly can be technically accomplished. And at times it might be cost effective. So it deserves more evaluation. (And if that evaluation is happening behind closed doors, and is failing economically, so be it -- it just never seems to be one of the proposal options).
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Old 11-22-2013, 02:31 PM   #1563
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Re: Crazy Transit Pitches

So what CAN be done with the mass ave corridor then? Just as downtown is only going to grow, Mass ave will follow, as it has for the last hundred years.

Matt suggested bus lanes, but I just don't seeing that working for long, if at all. Double length buses maybe will get us a further 50 years, but eventually I think its going to need rail.
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Old 11-22-2013, 02:58 PM   #1564
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Re: Crazy Transit Pitches

Bus lanes -> tram is the natural capacity expansion option.

I know it's a tough sell politically. At some point as a city we're just going to have to pull out something like Zurich's Transit Priority program and make a decision. They faced something like what we're talking about back in the 70s, except that they actually did have the option to do subway tunneling. Instead, a popular movement pushed for the prioritization of surface transit, and leaders went with it.

It probably won't happen neatly, but what does?
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Old 11-22-2013, 03:21 PM   #1565
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Re: Crazy Transit Pitches

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F-line, I don't want to have a pissing contest about this.

I understand that a water storage tunnel is not equal to a double bore transit tunnel. The transit tunnel is much more complex.

All I am trying to suggest is that the default position, in Boston, is always cut and cover tunneling. But there are definitely examples from other dense urban areas where deep bore tunneling can be competitive in terms of total construction cost, and come out ahead in terms of economic benefits. Cut and cover causes a lot of economic dislocation to the surface right-of-way above the cut, and this is rarely factored into the official project costs.

And I get burned when people suggest that a technique cannot be done technically (deep bore tunneling in clay and gravel fill), when it clearly can be technically accomplished. And at times it might be cost effective. So it deserves more evaluation. (And if that evaluation is happening behind closed doors, and is failing economically, so be it -- it just never seems to be one of the proposal options).
You're assuming that politicians cook up an engineering schematic in their own vacuum whenever presenting a proposal. That is totally false. Nobody presents a civil engineering proposal to a wider audience without getting a prelim engineering feasibility assessment from real engineers. Politicians aren't qualified, actively practicing engineers. You don't even have a basis for ballparking project costs without that assessment. Pols would be putting foot-in-mouth every other week going public saying they're all-in on kooky fantasy stuff that violates the laws of physics. On their turf those kinds of unforced errors erode their power and influence. Even the worst grandstanders aren't that stupid.

A need gets identified in a needs assessment, and the engineers are brought in on Day 1 to assess feasibility. Then there's a scoping study. It may have 20 different scenarios with 18 of them totally impractical and guaranteed to be eliminated before any preferred alternative is chosen. But ALL of them are vetted for feasibility. You will never see it on a piece of paper if it's physically impossible or so insanely difficult no reputable engineering firm would ever bid on it.

Firms like Parsons Brinkerhoff--the ones who do have the resources and know-how to do literally any civil engineering megaproject you can dream of--won't take $∞ to march its reputation off a cliff building to an engineering spec doomed to fail. They have a reputation to uphold, and needless risk or needlessly inefficient engineering arbitrariness costs them future contracts. Firms like that crap so much bigger'n than Boston and one individual project in Boston that they will walk away if they get told to do something that binds their hands past the point of futility. It not only doesn't get built, the pols get left at the altar to their own--on their turf--humiliation if nobody worth a damn bids on their micromanaged turkey.

Even the boondoggles like the Big Dig and Chinatown BRT tunnel got ruled solid on engineering feasibility and the most straightforward possible prelim designs greenlit when they advanced to a final cut of preferred alternatives. If there were problems in the value the state got out of it, it was the administration of the project (Big Dig) or flaws in the needs assessment (BRT vs. LRT) that hurt them. Not the engineering design. The designs did what they were supposed to do. Even the Big Dig's leaky slurry walls. They didn't choose that because it was "imaginative" or because they were up for a challenge. They chose it because it was the simplest path to satisfying the project needs for equal-or-better road capacity within the Central Artery footprint without blowing up any more adjoining blocks.


Yes...you are making an argument out of spite saying that because X construction technique was used somewhere that it can be used anywhere. Starting from a "must be deep-bore" stance and assuming that insiders who disagree are "unimaginative" is EXACTLY what you're blaming them for doing with cut-and-cover. It has no relevance whatsoever. No engineering firm is going to recommend the hardest possible build over something more straightforward. It's bad business. Triple the cost of the build over some aesthetic OCD and there's no contract to bid on because it can't be funded. And it's bad business for the politicians who want the pork to insist on stuff that can't be delivered.

If deep bore gets panned on the engineering assessment and all the firms capable of building it say cut-and-cover is the only sane and risk-managed way to do it, you can kick and scream all you want. It doesn't get built any other way. Go march into Parsons Brinkerhoff's offices and game out projects with them. Then try to convince them they're wrong, you're right, and it's their fault for not being creative enough when one of their recommendations doesn't have an elegant enough construction method for your taste. Try to shout over them when they explain that ain't their business model.



Pointless...Transit OCD...nihilism. If you want to build a Tappan Zee Subway in this town to show 'em they're all idiots, go dig up Robert Moses. The real world--warts and all--has long since moved on from civil engineering by spite.
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Old 11-22-2013, 04:10 PM   #1566
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Re: Crazy Transit Pitches

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Bus lanes -> tram is the natural capacity expansion option.

I know it's a tough sell politically. At some point as a city we're just going to have to pull out something like Zurich's Transit Priority program and make a decision. They faced something like what we're talking about back in the 70s, except that they actually did have the option to do subway tunneling. Instead, a popular movement pushed for the prioritization of surface transit, and leaders went with it.

It probably won't happen neatly, but what does?

Several things can be done, in no particular order.

1. Signal coordination. Most of the Boston stretch is on old 'dumb' mechanical-switched traffic lights. It's plain as day to see how uncoordinated the lights are with each other. The whole Boston-side corridor needs to be resignaled for better flow. And yes, if you do that, bus transit priority is possible. The same optical sensors that can detect the shape of a trolley on the C reservation can detect the shape of a bus in mixed traffic. That's exactly how transit priority works in other cities, and exactly how emergency vehicle preemption works in many places in this city.

2. General roadway reconfiguration. Central-Charles River got a lot better in that arduous road reconstruction. The curb bump-outs, the traffic calming features, the lane re-striping to better organize things and dilineate turn lanes, the traffic light resignaling. It really isn't half as bad a stretch as it used to be. The Boston side needs that badly. They have to take more parking at the corners to do proper protected left-turn lanes where possible instead of incoherent shit like this (nice...the corner parkers are even blocking the bus stop). The bus stops need real turnouts instead of...well, shit like that^. Major intersections vs. minor intersections need more divergent signal timing. It may be appropriate to keep Beacon, Boylston, Huntington, Washington on constant cycles...but a bus definitely needs to get a prioritized green on Marlborough, Belvidere, Westland, and probably every-other South End throroughfare where the east-west street redundancy gets a bit excessive. And so on.

3. Ditto Harvard-Route 16. The number of uncoordinated side street traffic lights with zero turn lanes and parking to the corner is insane. And pointless. That whole stretch of 77-riding death would flow twice as good with real turn lanes and coordinated signals. Plus real curb bump-outs for buses and parking. Add transit vehicle priority and the buses can make good time through all those 20,000 lights controlling minor side streets. It's like they're not even trying out here.

4a. Fix Hynes station. The southbound bus shelter needs to have its underground passageway to the subway station reopened. The security risk that originally closed it is mitigated in the security cam era. That Newbury-Boylston stretch needs better-controlled pedestrian movements. And they ought to put a proper northbound turnout, shelter, and widened sidewalk when the air rights get built on this triangle. This major transfer point is just an all-around mess for every user of Mass Ave., Boylston, Newbury, the Green Line station, sidewalks, and crosswalks.

4b. Fix Porter station. Northbound needs a bus turnout instead of blocking the Somerville Ave. turn lane and borking traffic for several blocks. Reconfigure the shitty concrete plaza waste of public space in the package.

5. Bootstrap onto MIT campus plans. They toy in some master vision planning document with the idea of doing a Harvard-style burial of Mass Ave. and surface mall on the Vassar-Grand Junction-Albany block to hide all the thru traffic in a duck-under and redevelop that as a campus Square with surface movements only for turning onto Vassar/Albany. I don't know how serious they are about it, but if a wad of money simply must be given to MIT for giving-them-money's sake that's a significant bottleneck solve to keep in mind for the deep future. Plus sets up a nice surface transfer between the #1 and Urban Ring.

6. Stop half-assing the CT1. That was supposed to be a major transit initiative: a real, extensive express bus system interfacing with all modes. It barely begun before it got relegated to the dustbin. Get a real service plan. They drew up one 20 years ago.

7. Articulated buses. 1 and 77 aren't fed by any garages with artics. Next vehicle orders need to spread the wealth. Of course, artics need to have bus stops that aren't perpetually blocked so that's enough excuse to get cracking on roadway improvements to the Boston side.




That's not as sexy as a rail line, but collectively that buys a very well-functioning bus corridor vs. 2 stretches (Boston and Harvard-16) that are among the very worst-functioning today. Simply because of lackadaisical layout, signaling, and turnout (or lackthereof) oversights. You don't even have to do the expensive MIT cover job to get an on-time 1 and 77. Just do what they did from Central to the Charles (and are about to do in Arlington) top-to-bottom on the corridor and they'll be reliable routes. Then get their CTx house in order and make that service the game-changer it was originally supposed to be.

I think that's good enough to serve the corridor's needs for another 20 years. Lazy negligence on the very basics of traffic flow shouldn't require a megaproject to solve it. We'll never know what the needs are if they let the existing stuff keep performing like ass. Do the mini-projects and find Mass Ave.'s true level. I bet it's a lot higher than you'd think.
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Old 11-22-2013, 04:35 PM   #1567
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Re: Crazy Transit Pitches

Turnouts won't do buses any favor. They're a benefit to drivers. Gets the bus out of the roadway. Then when the bus tries to return to traffic flow, the drivers won't let it merge back in. Happens all the time. Turnouts should only be used where dwell times are guaranteed to be long. Otherwise, curb bump outs which actually reach up to the level of the bus to achieve as close to level boarding as possible.

Also, I'm skeptical of BTD's ability to program "smart" traffic lights in a way that doesn't screw pedestrians. Just look at how bad it is with the buttons. I've experienced super-fancy infrastructure in places like California where the cars get all sorts of sensors and queue-adjusting cycles, but the pedestrians have to wait 5 minutes for a phase. It's bad enough here. I know BTD is improving, but still...
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Old 11-22-2013, 04:52 PM   #1568
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Re: Crazy Transit Pitches

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Turnouts won't do buses any favor. They're a benefit to drivers. Gets the bus out of the roadway. Then when the bus tries to return to traffic flow, the drivers won't let it merge back in. Happens all the time. Turnouts should only be used where dwell times are guaranteed to be long. Otherwise, curb bump outs which actually reach up to the level of the bus to achieve as close to level boarding as possible.

Also, I'm skeptical of BTD's ability to program "smart" traffic lights in a way that doesn't screw pedestrians. Just look at how bad it is with the buttons. I've experienced super-fancy infrastructure in places like California where the cars get all sorts of sensors and queue-adjusting cycles, but the pedestrians have to wait 5 minutes for a phase. It's bad enough here. I know BTD is improving, but still...
Well...if they don't give a shit, it's not going to get better. So give up?

No. How about trying to make them give a shit? Cambridge did that with the Central-Charles stretch and fixing the Main St. intersection. It worked wonders. It's not a perfect stretch of road, but it's performing to inherent capability whereas it didn't before. And that's proven to be a good thing. If you don't even know what the corridor's true level is, you can't evaluate its future adequacy or quantify the need for a big build.

If the City of Boston doesn't care about improving Mass Ave. with relatively minor things, it's not going to care about doing something dramatic with transit. That's half the problem we face today: City Hall isn't an advocate for maneuverability. Big or small. Are we really going to rest the whole motivation for doing really big things on their lack of motivation for doing really basic, common sense things? That's buying into the very same "We've always done it this way" mentality with one hand while shaking fist at it with the other. What kind of logic is that?

Doing something creates momentum for doing something bigger. You're not getting a better Mass Ave. corridor until they put in the work to make traffic, the 1, and the 77 work better. If BTD needs to get slapped hard to make that happen...there's something to get motivated for. It won't create interest in a rail line to lose interest in the bus lines.
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Old 11-22-2013, 05:12 PM   #1569
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Re: Crazy Transit Pitches

I think that the single best thing that would help the 1 is POP to decrease the long dwell times.
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Old 11-22-2013, 06:17 PM   #1570
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Re: Crazy Transit Pitches

Well explain to me how turnouts help buses, instead of simply increasing average clearance times?
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Old 11-22-2013, 07:11 PM   #1571
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Re: Crazy Transit Pitches

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Well explain to me how turnouts help buses, instead of simply increasing average clearance times?
Sometimes a bus has to stop for a long time (e.g. if someone with a wheelchair is getting on and off) which would unduly backup traffic and make things worse for everyone (including other buses) on the corridor. Do buses have priority in Boston when pulling out? If not they should, otherwise it should be enforced with onboard cameras on the bus.
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Old 11-22-2013, 07:37 PM   #1572
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Re: Crazy Transit Pitches

If the MBTA were to have street running rail on Mass Ave, where would the terminuses be located? Would it stop at Central for people to transfer to the Red Line or go further?
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Old 11-22-2013, 08:16 PM   #1573
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Re: Crazy Transit Pitches

It would probably have to go past Prospect, left on Pleasant, left on Franklin, left on Magazine.
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Old 11-23-2013, 12:58 AM   #1574
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Re: Crazy Transit Pitches

Sometimes it does have longer dwell time, but by far the common case is that the bus is held up by other cars refusing to let it merge. Another issue is caused by the fact that turnouts are usually blocked by parked cars, so the bus isn't able to pull to the curb and get quicker level boarding anyway. That slows dwell time too.

As far as I know, there is no law giving bus priority in merging. And even if there was, it would probably be enforced as much as the speeding laws, or the crosswalk laws.

IOW, never.
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Old 11-23-2013, 11:09 AM   #1575
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Re: Crazy Transit Pitches

^ Just to reiterate what F-Line said: what's there to do then? You sound defeated. If the cops won't enforce the laws and that's that, then there's no real changes you can make is there?
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Old 11-23-2013, 12:09 PM   #1576
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Re: Crazy Transit Pitches

I was thinking that most of an urban ring subway route could be done with cut/cover. There are only a few places I think that deep bore would be necessary one of which is under Harvard Station in Cambridge where apparently it is possible to deep bore. Now the rest could be cut/cover down Harvard Ave thru Allston and Brookline. It would be a huge pain in the ass, sure, but the pay off would be tremendous. The ease of mobility to Cambridge from just outside the downtown core would be insanely easier as well as less congestion in the downtown core itself. You all know that.

The point is that only a very limited amount of the project on the route would be deep bore. Basically I think just a connection between what is being cut/covered on either ends of Harvard Sq. would need to occur and if deep bore is possible there, the less disruption there would be to activities in the congested bustle of Harvard Sq.

I really think it could be done. As much as a temporary pain it would be to cut and cover these major thoroughfares, the payoff would help everyone that commutes on the T.

I see it possibly playing out as:

Cut and cover from Sullivan down Washington St. in Somerville
Continue cut/cover down Kirkland St. in Cambridge
Bore under Harvard Station continue under Charles River to N. Harvard St.
Cut/cover down N. Harvard St >> Cut cover down Franklin St. in Lower Allston
>>Cont. cut/cover down Harvard Ave thru Allston and Brookline....

...The rest could basically be cut/cover all the way to JFK/UMASS
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Old 11-23-2013, 01:27 PM   #1577
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Re: Crazy Transit Pitches

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^ Just to reiterate what F-Line said: what's there to do then? You sound defeated. If the cops won't enforce the laws and that's that, then there's no real changes you can make is there?
Build the physical infrastructure so that the buses can quickly unload and load. Curb extensions, approximating level boarding as much as possible, in-lane.
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Old 11-23-2013, 02:55 PM   #1578
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Re: Crazy Transit Pitches

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Originally Posted by c_combat View Post
I was thinking that most of an urban ring subway route could be done with cut/cover. There are only a few places I think that deep bore would be necessary one of which is under Harvard Station in Cambridge where apparently it is possible to deep bore. Now the rest could be cut/cover down Harvard Ave thru Allston and Brookline. It would be a huge pain in the ass, sure, but the pay off would be tremendous. The ease of mobility to Cambridge from just outside the downtown core would be insanely easier as well as less congestion in the downtown core itself. You all know that.

The point is that only a very limited amount of the project on the route would be deep bore. Basically I think just a connection between what is being cut/covered on either ends of Harvard Sq. would need to occur and if deep bore is possible there, the less disruption there would be to activities in the congested bustle of Harvard Sq.

I really think it could be done. As much as a temporary pain it would be to cut and cover these major thoroughfares, the payoff would help everyone that commutes on the T.

I see it possibly playing out as:

Cut and cover from Sullivan down Washington St. in Somerville
Continue cut/cover down Kirkland St. in Cambridge
Bore under Harvard Station continue under Charles River to N. Harvard St.
Cut/cover down N. Harvard St >> Cut cover down Franklin St. in Lower Allston
>>Cont. cut/cover down Harvard Ave thru Allston and Brookline....

...The rest could basically be cut/cover all the way to JFK/UMASS
The problem with Harvard is that if you undercut the station you have to nuke and rebuild the station. The whole thing is crammed around the contours of the Square, the abandoned Eliot tunnel, the bus tunnel, and all the pedestrian connections. It's a shitload of interfacing, load-bearing infrastructure of varying depth and wildly varying ages all converging in the same spot. With none of the bedrock Porter has, which means more reinforcement of above structures and even deeper depth than Porter if you go down and off- street grid. They did all the surgery that was possible from 1979-81 to remake the Red Line while keeping it, the buses, and the Square in operation during the disruption. There's no such option now if going lower requires tearing out the floor to underpin it, or burrowing 250 ft. below ground instead of 100 ft. like Porter and making transfer movements at such a busy station entirely elevator-dependent.

Trying to clean-room all of that gets to my point: how big a boulder pushed up how steep a hill before the effort becomes self-defeating? Taking Harvard Sq. out of commission for years isn't an option, and neither is building a station so deep that high-volume foot traffic between station levels is nearly impossible.



And this 66 subway? You're tunneling several miles down a motley collection of streets of varying widths. All packed as dense as possible with the densest residential in Allston and the densest commercial in Brookline. A water crossing. Uphill tunneling in Brookline. Sharp curves. Between construction, mitigation, and economic ruin from shutting down entire blocks of this corridor for years at a time...this is easily a $20B project. And worse, it will evict too many existing businesses and residents: the ones who simply won't survive the years their street grid is disrupted to uselessness, and the many more afterwards who get priced out before the area has even had a chance to recover from the disruption.

Who is this an economic benefit for? Not the people using the 66 or making a living off the 66. It's for the future people who'll replace them when they get squeezed out. That's not a neighborhood transportation improvement. It's urban renewal...renewed. Understand what unintended consequences that brought about the last time, and understand what failure to learn from history buys you. You can't just assume that such a project will be more careful and benign than bad old urban renewal. When the act of undertaking a project like this wreaks this level of long-duration disruption...displacement of the neighborhood becomes a 'feature', not a bug.

Please do consider this when drawing your fantasy transit maps. Transit equity is sacred enough that what you choose to build and how you choose to build it has to take into account disruption, and the corridor's resiliency against disruption. You can't just look at pretty lines on the map as a finished product. If it's going to take whole segments of Mass Ave. or the Allston and Brookline street grids offline segment by segment for close to 20 years, somebody is getting sacked with a whole lot of mobility loss that will not be repaid to them. It'll be repaid to the more fortunate who displace them. That's transit inequity. And the urban renewal tragedy all over again. Choosing the hardest possible path because it must be so isn't learning from those mistakes.



Now...back to the Big Dig and why it was designed the way it was. The needs assessment for that project was to keep it entirely in the footprint of the elevated Artery so nobody else got displaced by the terrible mistake they made when the original Artery was built. The slurry wall cut-and-cover was explicitly designed to minimize disruption by jacking up the existing highway when the original underground supports had to be taken out, and preserving the street grid through the duration. The North End, street grid, and all highway circulation inside 128 could bend within tolerances but not break during the years of disruption, the area of disruption stayed self-contained, and the new highway got the simplest possible design for increased capacity without widening its footprint. Of all the things that went wrong during that project, construction mitigation wasn't one of them. The affected neighborhoods were less affected than some feared, and actually thrived during the project.

The same was true when Harvard Sq. got torn up for the new Red Line alignment. They kept all the transit operating at full capacity with full mitigation--2 stations load-spreading the capacity, and fully undisrupted bus service. They chose the design that was not 'perfect' for ops with that sharp curve, but which had the shortest-duration construction through the Square and most mitigation options for keeping businesses afloat. They were done cutting up the street through Cambridge Common in under 2 years. They would not have been if they chose a more elegant routing that severed the Red Line or bus tunnel during construction, required tearing up part of Harvard Yard, or required years longer drilling of shafts through the Square and undercutting buildings for a deeper station. They didn't do it with the expectation that all the weaker native businesses would probably be on their way out as direct result of the disruption (over-gentrification came way way later and mostly at the hands of Harvard itself). It was done with the explicit intention that they'd be unscathed during construction and thrive...not be displaced...after it.

The same shapes other transit projects. The Transitway got bundled in with the Big Dig and Ted with a routing through Seaport moonscape. The N-S Link could've been bundled into the same package, but instead is pre-provisioned to have no disruption to anything in the main tunnel, to burrow under rail yards and 5-track ROW's in Pike and Leverett ramps no-man's land elsewhere, and to handle its trickiest stretch at SS by straddling Dot Ave. and the Channel at a spot where all the other tunnels were pre-prepped to have another tunnel threaded between while remaining in service. Every other proposed rapid transit extension of the postwar era--GLX, Blue to Wonderland and beyond, Braintree branch, the D line, relocated Orange Line, Red from Davis station--bootstrap onto RR ROW's. So do the unbuilt ones: entire north half of the Urban Ring, further Orange extensions in both directions, Red-Lexington, Blue to North Shore, Green to Needham.

The ONLY ones that involve invasive tunneling are the shortest possible gap-fillers: Orange from Chinatown to Back Bay to get on alignment (done 20 years before it actually opened while the neighborhood was in the act of being urban renewal-wiped), Red from Harvard to Davis on the path of least destruction, North Station superstation, Red-Blue on only a few blocks of supersize Cambridge St. Ditto some of the unbuilt unofficial proposals we frequently talk about: recycling the Tremont tunnel and Pike canyon to connect Back Bay and Green with the Seaport, recycling the B reservation footprint to BU Bridge to link Urban Ring LRT to the Green Line, burying the E reservation and limiting the street-level disruption to 1/2 mile between Brigham Circle and Brookline Village, reserving a path through remade Beacon Park and Harvard's Allston land to bring an Urban Ring spur to Harvard Sq. (maybe first in mixed traffic from the bridge to the bus tunnel, then in a new Charles crossing), taking advantage of the rock-solid Milton-Mattapan granite and lack of tall buildings to deep-bore a future Ashmont Branch extension under the 2000 ft. between Mattapan Sq. and the Fairmount ROW to reach Hyde Park, trading in Storrow for a shallow semi-surface Riverbank subway extension of the Blue Line from Charles. And so on.

What are the common themes here? They're all carefully risk-managed on the disruption, stick as closely as possible to pre-cleared space and previously available ROW's, and do as little invasive tunneling as humanly possible to get from Point A to Point B and meet all the key points of the needs assessment. They use the most minimalist engineering as feasible to get the job done, even when that's less perfect as what's engineering possible with enough might. They do not force displacement or temporarily acute economic hardship on their surroundings as a construction necessity.

The ones that don't get built are the shakiest on disruption. Silver Line Phase III's disruption to Chinatown and the Common, plus its required mitigation, proved killer. Ditto the cross-Brookline tunnel envisioned for the Urban Ring...too much unnecessary destruction when a more roundabout LRT routing via a B Line subway, Kenmore, and the D recycles existing infrastructure. In each case, however, the engineering assessments said that was the most risk-managed way to build BRT tunnels through urban density. But that's more an indictment of the needs needs assessment mandating the BRT mode than it is intentionally choosing a harder engineering job for mapmaking perfection.

So do you see where the 66 and Mass Ave. subways fall on the side of this divide? The sheer complexity and disruptiveness of the builds IS a flaw of the process that identified those builds as the only way to fill a need on those corridors. Have other lower-impact projects been gamed out well enough to see how much they can indirectly help these corridors? Does the 66 even have to travel its current route, or would reshaping its ridership onto Urban Ring LRT relieve enough end-to-end load to make it a better bus for each individual segment? Have we even begun to exhaust Mass Ave. improvements to the 1 and 77, and how much would an Urban Ring through MIT, a Dudley streetcar, an Arlington Ctr. Red Line extension, and a Porter Sq. Green Line extension divert those loads? Have we even answered these questions fully, or are we just looking for the prettiest 2D lines on a map?
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Old 11-23-2013, 03:14 PM   #1579
F-Line to Dudley
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Re: Crazy Transit Pitches

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Originally Posted by Matthew View Post
Build the physical infrastructure so that the buses can quickly unload and load. Curb extensions, approximating level boarding as much as possible, in-lane.
I really don't have any strong opinion one way or the other on curb cuts for buses, other than it's usually part-and-parcel with the streetscaping package when all those other common-sense improvements get done. The main thing for boarding is taking the parking spots away and controlling the parking spots with curb bumps so blocking bus stops isn't the epidemic it is today. And so the buses don't clog the middle of the road and don't harm accessibility by stopping so far from the curb. Whatever's the best means to end for doing that is fine by me. And it may well vary corridor-to-corridor. Just get it done. The senseless inefficiencies on the Boston side of the river are what's killing the 1 more than anything else.

If people don't want to obey the laws and BTD doesn't give a shit about giving transit vehicles the right of way, that's a people problem not a bus route problem. People can change. Give them a threat on their turf and the most lackadaisical pols will spring into action. But don't assume a behavioral problem is permanent because it's always been that way. Find a better way to make it translate and resonate onto their turf. You don't get capital money spent without doing that. You won't get quality-of-service improvement either. It's all the same: action gets taken when the people who move the resources around either get amply motivated or have to defuse a threat that affects them.
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Old 11-23-2013, 03:19 PM   #1580
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Re: Crazy Transit Pitches

Quote:
Originally Posted by F-Line to Dudley View Post
What are the common themes here? They're all carefully risk-managed on the disruption, stick as closely as possible to pre-cleared space and previously available ROW's, and do as little invasive tunneling as humanly possible to get from Point A to Point B and meet all the key points of the needs assessment. They use the most minimalist engineering as feasible to get the job done, even when that's less perfect as what's engineering possible with enough might. They do not force displacement or temporarily acute economic hardship on their surroundings as a construction necessity.

The ones that don't get built are the shakiest on disruption. Silver Line Phase III's disruption to Chinatown and the Common, plus its required mitigation, proved killer. Ditto the cross-Brookline tunnel envisioned for the Urban Ring...too much unnecessary destruction when a more roundabout LRT routing via a B Line subway, Kenmore, and the D recycles existing infrastructure. In each case, however, the engineering assessments said that was the most risk-managed way to build BRT tunnels through urban density. But that's more an indictment of the needs needs assessment mandating the BRT mode than it is intentionally choosing a harder engineering job for mapmaking perfection.

So do you see where the 66 and Mass Ave. subways fall on the side of this divide? The sheer complexity and disruptiveness of the builds IS a flaw of the process that identified those builds as the only way to fill a need on those corridors. Have other lower-impact projects been gamed out well enough to see how much they can indirectly help these corridors? Does the 66 even have to travel its current route, or would reshaping its ridership onto Urban Ring LRT relieve enough end-to-end load to make it a better bus for each individual segment? Have we even begun to exhaust Mass Ave. improvements to the 1 and 77, and how much would an Urban Ring through MIT, a Dudley streetcar, an Arlington Ctr. Red Line extension, and a Porter Sq. Green Line extension divert those loads? Have we even answered these questions fully, or are we just looking for the prettiest 2D lines on a map?
F-Line -- this is very well expressed and explained. There is a ton of complexity here that is very difficult to balance.
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