If You Were God/Goddess | Transit & Infrastructure Sandbox

Went on a mind thought train and categorized transit routes into 2 categories.

A: All dedicated transitways, these can be rail tunnels, rail stub tracks, dedicated busway tunnels, or abandoned railways. Subway tunnels are differentiated from dedicated ground level rail lines that funnel from North Station, South Station, or the BRB&L terminals. This includes the stub track and the SL transitway in South Boston.
B: All street running routes and on street streetcar routes. This means the B, C, and E streetcar trolley lines are categorized with the buses, west of Kenmore, outside the tunnels.
Categorizing this way, this makes it easy to see where rail routes must define rail replacement shuttle bus routes, separate from bus routes and streetcar/trolley lines.

Inner boston core transitways and railways current/historical/abandoned, plus the rapid transit branches to Braintree via Quincy Center, and Riverside. I've also added the Watertown Branch extension to Waltham Center, even though it's outside of the inner core.
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From this map, without using the North-South Rail Link, all rail lines on this map, are able to be fed directly into the subway tunnels past Downtown and through-run, on the other side, with the exception of the Fairmount line.

All northern routes are able to be fed into the Orange Line tunnel, with the exception of the Blue Line, and the B&M East Boston Line along Route 1A in East Boston. The Minuteman Branch can be fed into the Red Line tunnel. All branches that pass through the core of Somerville (E. Somerville/Union Sq) can also be fed into the Green Line tunnel.

All southern routes are able to be fed into the Orange Line tunnel, with the exception of routes that can be fed into the Red Line tunnel, and the Fairmount Line. The Highland Branch can be fed into the Green Line tunnel, but historically connected to the ROW that can feed into the Orange Line tunnel, so we'll say it can feed into both GL and OL tunnels.

Here are some of my thoughts on connecting existing transit and rail lines to form rapid transit lines, before adding new lines or digging new tunnels:

1. The Red Line tunnel will add a connection to Waverley. Braintree trains would be assigned to run to Waverley, as it could potentially be extended to Waltham Center, and Braintree trains serve Quincy Center. Ashmont trains will travel to Arlington Heights Busway. The Mattapan via Neponset line will be sent to terminate in the Seaport district via the Convention Center.
2. A rapid transit line would run from Waverley, to Davis, to East Somerville, then loop northwards to continue to Wellington to Linden Sq. This provides a one seat ride between Gilman Sq. and Davis. This is a crosstown connection line.
3. A rapid transit line from Newton Corner, then use the entire Grand Junction ROW. This is a crosstown connection line.
4. Aside from those two lines, Wellington Station would see the Medford Sq. Branch and Oak Grove Branch travel into downtown. The main corridor for Linden Sq. and the Chelsea-Revere line would travel to downtown via Everett. So 2 branches on each corridor.
5. For the Green Line, the Medford Branch would be extended to West Medford. There are now only 3 branches, as I removed street running service from the Green Line central subway tunnel due to reliability issues of street running traffic. Watertown Branch trains will be assigned to run through the Pleasant St. portal. West Medford trains will run through the Symphony portal (tunnel extension to cover the rest of the E branch). Arlington Heights trains will run via Porter and Union Sq., and continue through Kenmore (service continues on the D branch through Reservior).
6. On the south side, since the Medford Sq. and Oak Grove Branches are shorter, they will be assigned to run the longer routes to Dedham Mall and Wolcott Sq. Readville. Oak Grove trains will continue due south to Readville, Medford Sq. trains will curve westwards to Dedham Mall.
7. Linden Sq. via Everett trains will travel to Newton Corner, Chelsea-Revere trains will travel to West Roxbury VA Hospital.
8. The Orange Line tunnel is already responsible for now carrying 4 branches. However, there are currently no direct one seat service between Community College to any of the Somerville based rapid transit routes, even though there are 2 potential routings to reach Somerville from Community College. Charlestown riders must travel to Sullivan or North Station to transfer to a Somerville based route.

The Blue Line is mostly self contained, aside from extensions to Charles MGH, and potential extension past Revere/Revere St. to Lynn, which would continue to Salem Depot and Beverly. The B&M East Boston branch is mostly industrial along Route 1A, so unfortunately, I'm not sure if that line holds much value for connection. It does bring East Boston riders closer into the core portion of Revere, as opposed to Revere Beach, which is slightly further away from the core of Revere than the B&M East Boston branch. For now, it could be fed into the Blue Line tunnel.

The Fairmount Line is currently not connected and currently dead ends at South Station. The same is true for the Seaport Transitway.

Anyhow, these are my thoughts. I've left the map blank, since there's a lot of permutations on how to connect each line. The map here only extends to the extent of streetcar suburbs, as further out, the permutations for branches increases dramatically. Some ideas of note:

1. Use as many historical/existing lines as possible. There is no need to: use every junction in areas with more than 1 junction; or to use every dead end line in East Boston or South Boston.
2. Consider disconnecting the Green Line tunnel from all street running services, and only serve lines that are not street running. You may convert the Green Line tunnel to heavy rail if desired. This is due to reliability issues with street traffic, and the 4 street running branches decreasing capacity in the central tunnel.
3. Extra non-existant ROWs or tunnels that aren't current or abandoned are mostly not in scope of this. There are potential extensions of the Green Line subway tunnel from Symphony to Brigham Circle to Arborway, or Pleasant Street to Nubian to LMA/Forest Hills. Aside from that, the scope here is to reuse as many existing and former rail lines, and to minimize new tunnel/ROW digging. The idea here is the best way to optimize through running existing/historical ROWs. New metro tunnels could be dug under existing bus routes, so new tunnels would mostly be identifying Key Bus routes to dig subway tunnels underneath them.
Because the NSRL has a snowball's chance of being built in the foreseeable future, I like your concept of setting up the commuter rail lines to feed directly into the rapid transit lines, providing commuter rail continuity through downtown and other areas. Great job!
 
Because the NSRL has a snowball's chance of being built in the foreseeable future, I like your concept of setting up the commuter rail lines to feed directly into the rapid transit lines, providing commuter rail continuity through downtown and other areas. Great job!
Except for those pesky FRA/FTA regulations
 
Except for those pesky FRA/FTA regulations
There are a lot of details to work out. But what if the rolling stock on the commuter rail were replaced with subway tunnel friendly dimensions, EMU drive train, etc., but preferable electrifying the commuter rail lines, with train sets having combo 3rd rail/overhead line capability similar to the Blue Line cars. I think it's technically doable. The FRA/FTA regs would have to be dealt with for sure.
 
Because the NSRL has a snowball's chance of being built in the foreseeable future, I like your concept of setting up the commuter rail lines to feed directly into the rapid transit lines, providing commuter rail continuity through downtown and other areas. Great job!

Commuter Rail oftentimes runs less frequently than transit services in the inner core. In the case of the map shown, the portion of the routes within the inner core would be short turn high frequency routes (every 4-7 minutes), and commuter rail would be lower frequency routes (every 20 - 30 minutes), outside of the MBTA bus district area. I suppose the area in between Route 128 where the buses stop, and the inner core where the streetcars ran, would have demand for service every 12-30 minutes. Therefore, 2 short turning locations on each line would be needed. I suppose, in a open transit infrastructure sandbox perfect lines map, all the lines could be quad tracked or more within the inner core of Boston.

For example, the West Medford line:
1. Every 4-7 minute service to West Medford. Rapid transit trains would then short turn at West Medford, and then return to Boston.
2. Once outside West Medford, frequency decreases to every 12-30 minutes on the mainline. Trains will operating here will be a regional rail model of service, not a rapid transit model of service. I suppose individual branches outside the MBTA bus service area would be every 30 minutes.
3. With so many lines running into the rapid transit tunnels, and most of the capacity eaten by the inner core rapid transit services every 2-4 minutes with combined branches, outer core Commuter Rail trains would probably still need a dedicated NSRL tunnel, or terminate at the large terminals at North/South Station.

4. An exception would be made to Lynn's Central Sq., Waltham Center, and the now current Braintree and Riverside (Highland branch) terminals, with service at 6 - 13 minute frequencies.

Again, the Orange Line tunnel is already responsible for carrying a hypothectical 4 branches with high frequency service across the inner core streetcar suburbs. There may either be 4 branches feeding into a single track per direction every minute, or 2 tracks per direction carrying 2 branches each at 2 minute combined frequencies to the streetcar suburbs on the other side of town. In this case, it would be at the capacity that the Green Line Central Subway tunnel is currently, with 4 branches.

It just so happens that the Orange Line tunnel has a ROW connection to almost all the inland rail routes. In the case above, you may well overwhelm the Orange Line tunnel downtown with intercity commuter rail services into the outerlying suburbs. GL and RL tunnels would carry 3 branches each at 2 minute combined headways. BL downtown tunnel would carry 2 branches at 2-3 minute combined headways.

With how the historical rail network in the Boston area developed with so many branches feeding into a hub and spoke model, it is difficult to manage the many historical branches feeding into mainlines that need to be managed before a new tunnel or ROW needs to be created and built. In some cases, it will unfortuantely require a transfer, since the alternative would be individual branches with too little frequency, and the mainlines in the inner core downtown being extremely unreliable with too many branches.
 
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Except for those pesky FRA/FTA regulations
Exactly. You need to be using FRA/FTA compliant rolling stock -- and that means everywhere, because the subway section need have the rail changed out for heavy rail profile rail versus subway rail, to prevent derailments.

I don't think subway dimension rolling stock that is FRA compliant, and support catenary and third rail power, exists; so you are creating a unicorn.

Also subway power systems are different voltages than heavy rail catenary, so this absolutely does not work on the NEC or Haverhill lines with Amtrak mixed modes. (Or you are talking about totally repowering the entire subway system $$$.)
 
Between the FRA compliance, different loading gauges per line, wildly incompatible electrification schemes, differing design speeds for CR vs. rapid transit, and so on and so on...the cost of mods to the entire existing system would well exceed the cost of doing full-build NSRL.
 
I am sure @Delvin4519 is very much aware of the radical engineering challenges that would be associated with making this system in real life. To quote the opening post of this thread:
This is your "perfect world", "wipe the slate clean", "perfect lines on the map" infrastructure sandbox thread. Got an idea for something that has no good reason other than "it would be cool"? Or an idea that is so outlandish in terms of the financial, political, ethical, and/or engineering challenges that it would never happen in a million years? This thread is your playspace. Discuss concepts but don't bring in feasibility questions here. It's just for fun.

If you want your concept critiqued for feasibility, post it over in Crazy Transit Pitches and someone will probably dig into it.
@Delvin4519, I think this is a really interesting thought experiment, which highlights interesting dynamics about the real-world network and settlement density distribution. I also think it's an interesting idea to examine what the ramifications would be of a region-wide single-mode rail network -- definitely some benefits, and definitely some drawbacks. Good food for thought!
 
I am sure @Delvin4519 is very much aware of the radical engineering challenges that would be associated with making this system in real life. To quote the opening post of this thread:

@Delvin4519, I think this is a really interesting thought experiment, which highlights interesting dynamics about the real-world network and settlement density distribution. I also think it's an interesting idea to examine what the ramifications would be of a region-wide single-mode rail network -- definitely some benefits, and definitely some drawbacks. Good food for thought!
I completely agree that this is a great thought experiment.

As such it emphasizes we really need to build the NSRL with full regional electrification and a fleet of EMUs to get real Regional Rail capabilities.
 
So, let me start by saying that I AM NOT ADVOCATING FOR THIS NECESSARILY. There are parts I find attractive, and I will mention when I discuss parts that do.

So, the limiting factors are tunnel capacity and the need to meet Amtrak's need for access to Boston both on the NEC and Worcester Lines, and CSX's freight rights.

Let's assume that moving ROWs from FRA to FTA inside 128 would be relatively easy, and more difficult some distance outside, although the T has had plans to run the GL to Woburn(and a study to run it to Framingham)and the RL to both Brockton and Bedford.

I believe that 2 min frequencies on the RL and OL would be possible with presently installed/planned equipment, so that's our limit. There are systems that run more frequently, but let's not go there yet. Station lengthening becomes the other possible capacity stretcher. I leave it to others to discuss that.
This brings up the question of permanence of post-covid travel patterns. Could the WFH and hybrid patterns remain and what excess capacity does that give for dumping CR pax on the RT system?
Next, would adding battery power to some of the present RT rolling stock be feasible? Also, how much could top speeds be increased on said equipment (mainly the OL) without fundamental redesign. An operating speed of 75-80 would be helpful. I also assume that, like the BL, adding catenary to the OL and RL stock would not be particularly difficult.

So, let's start on the Northside. On the ER, the main question is from Salem out, or possibly Beverly out. Do you try to keep a one seat ride from Rockport and NBPT, or would this be a place where people ride a dinky to Beverly or Salem and then take the OL? There is also the issue of one remaining freight customer in Peabody, but for the purpose of this discussion, let's assume the parties involved can be bribed.
The other problem is freight access to Chelsea. I know others will disagree, but I think that a gauntlet track over the bridge would solve the issue.
That leaves the issue of which track needs to preserve freight access to Boston, which will be part 2.
 
The other problem is freight access to Chelsea. I know others will disagree, but I think that a gauntlet track over the bridge would solve the issue.

Well, this is God Mode, so I'd say that a gauntlet isn't needed, because the only way CR can come off the FRA mode at all is if we've God Moded CSX's trackage rights into oblivion, and if we can do that by fiat then we can time-separate out any remaining freights. (I assume for this purpose we'd just re-grind the HRT rails to RR profile because there's probably fewer miles of that than doing it the other way.)
 
Loading gauge is going to be the biggest problem here. Green Line has a car width of 8'8", Blue and Orange have widths of 9'3", Red has a width of 10'2", and Commuter Rail/Amtrak have a width of 10'6". There's 4 different floor-to-platform heights. RR's 10'6" width and 4 ft. height is the closest to a standard you're going to get, so it's a literal do-over of every single RT station, every single foot of RT tunnel, and track re-spacings of most of the surface RT ROW's.

I know this is God Mode, so God away...but if the comparison point is "building NSRL or not", building NSRL is going to cost less many times over.
 
Loading gauge is going to be the biggest problem here. Green Line has a car width of 8'8", Blue and Orange have widths of 9'3", Red has a width of 10'2", and Commuter Rail/Amtrak have a width of 10'6". There's 4 different floor-to-platform heights. RR's 10'6" width and 4 ft. height is the closest to a standard you're going to get, so it's a literal do-over of every single RT station, every single foot of RT tunnel, and track re-spacings of most of the surface RT ROW's.

I know this is God Mode, so God away...but if the comparison point is "building NSRL or not", building NSRL is going to cost less many times over.
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I've assumed that no CR equipment would be involved, but the opposite. So the do-over would be converting CR stations to OL or RL standards. That could be accomplished by a relatively easy track shift toward existing platforms and ballast addition on OL and an inch of removal on RL. I don't see where BL could go, and GL needs no platform. A minor issue comparatively. And in many cases, stations don't have any platforms yet, so doing so should be much less expensive as the lengths would be much less.
And don't forget, a massive platform campaign is necessary for RR as well.
 
I've assumed that no CR equipment would be involved, but the opposite. So the do-over would be converting CR stations to OL or RL standards. That could be accomplished by a relatively easy track shift toward existing platforms and ballast addition on OL and an inch of removal on RL. I don't see where BL could go, and GL needs no platform. A minor issue comparatively. And in many cases, stations don't have any platforms yet, so doing so should be much less expensive as the lengths would be much less.
And don't forget, a massive platform campaign is necessary for RR as well.
That would pretty much wipe the slate clean on freight anywhere in Eastern MA, as every RR car goes to the same 10'6" width and would need a gauntlet at every single station just to pass any common-carrier car by. Not to mention I'm not sure how you'd ever make that work with same-width Amtrak. You pretty much need the 'superset' standardized dimensions of RR to make anything work.

To give some sense of scale, a Commuter Rail single-level can board at literally any RR platform (assuming there's ADA lifts for low-platform territory, like Amtrak does with its trans-high/low LD's) on the North American continent. So the scale we're working with trying to rapid-transitize the Purple Line's dimensions is mind-bogglingly inverted.
 
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That would pretty much wipe the slate clean on freight anywhere in Eastern MA, as every RR car goes to the same 10'6" width and would need a gauntlet at every single station just to pass any common-carrier car by. Not to mention I'm not sure how you'd ever make that work with same-width Amtrak. You pretty much need the 'superset' standardized dimensions of RR to make anything work.

To give some sense of scale, a Commuter Rail single-level can board at literally any RR platform (assuming there's ADA lifts for low-platform territory, like Amtrak does with its trans-high/low LD's) on the North American continent. So the scale we're working with trying to rapid-transitize the Purple Line's dimensions is mind-bogglingly inverted.
Speaking of which, are there similar standards or recommendations for rapid transit dimensions?
 
So, Fitchburg Line has no freight use until Ayer, but I think that this is one line where a dinky into Littleton is the way to go, unless you run the outer trains up through Lowell.Either way, it would not be cost effective (a third track) to run FTA all the way.
The Red Line could be split before Alewife and half of trains be run out to Littleton and the other to Arlington heights or possibly Lexington.
The Haverhill Line next.
 
That would pretty much wipe the slate clean on freight anywhere in Eastern MA, as every RR car goes to the same 10'6" width and would need a gauntlet at every single station just to pass any common-carrier car by. Not to mention I'm not sure how you'd ever make that work with same-width Amtrak. You pretty much need the 'superset' standardized dimensions of RR to make anything work.

To give some sense of scale, a Commuter Rail single-level can board at literally any RR platform (assuming there's ADA lifts for low-platform territory, like Amtrak does with its trans-high/low LD's) on the North American continent. So the scale we're working with trying to rapid-transitize the Purple Line's dimensions is mind-bogglingly inverted.
Perhaps you should read my second paragraph?
 
Related to @Delvin4519's thought experiment, I am reminded of this mind-boggling fact: the majority (arguably a significant majority) of the MBTA rapid transit system is built along ROWs that were first built... 150 years ago.

Check out the 1875 map (and while you're there, check out the 1865 map and see how much is there too), and you'll see:
  • the entire Red Line (both branches) south of Andrew
  • the entire Blue Line north of Airport
  • the entire Orange Line, save for 1.5 miles across downtown
  • the Green Line from Lechmere north
  • most of the Green Line's Riverside branch (with a hilarious gap at the western end that reminds us of the fascinating way that line, and the Needham Line, were built)
To be clear, I'm not saying this is a bad thing; particularly outside of the urban core, the region was built up along the railroads, and we still see the patterns of that today. But I think it's really interesting to consider how much of crayon-mapping conversation these days is still directly impacted by decisions made 150 years ago.

(Also worth considering how much of our network was constructed by building subways across the central core which connected suburban railroads -- i.e. each subway line was essentially its own version of the North South Rail Link. Of course historically, that's not actually what happened; the subways were really built in conversation with the streetcar network, not the mainline. It was only in the 20s through 40s that we saw the subway lines being hooked up to the suburban railroads, starting with the Ashmont Branch. But the outcome has ended up being very similar.)
 
I keep seeing extending T service out to the burbs. How about densifying Dorchester, Roslindale and Mattapan? If the red line can be extended to Alwife, this could be reasonable. But I put it here instead of reasonable pitches because building tunnels$ just doesn't seem feasible these days. Also, I think its a shame that Franklin Park and Arborway is not on a subway so...
Extending the Red line from Ashmont to Forest Hills under Gallivan Blvd and Morton St and ending at a new storage yard at the old Forest Hill station. Extending the orange line thru Roslindale to Mattapan under Cummings and taking over of the red line extension yard with a small yard and loop. The red line extension can be extended over River St and take over the Auto Sales lot for a new station.
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It was supposed to be more of a napkin sketch of "how to grow Boston's underutilized suburban deserts by expanding public transportation". I'll stay in the crazy pitches since there is no supporting numbers to this effort.
 

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