MBTA Red Line / Blue Line Connector

[NoShJFK]

Here's some inflation adjusted numbers for those curious

According to the 2003 Program for Mass Transportation (PMT):

	Capital cost (2003 estimate, adjusted for inflation in 2023 $)	Ridership increase on mode
BLX Wonderland to Lynn	$598.0 mil	21,000
BLX Lynn to Salem	$608.3 mil	15,500
OLX to Reading	$487.8 mil	9,400
OLX to West Roxbury	$528.7 mil	11,300
GLX to Needham	$207.2 mil	3,400
RLX to Route 128 via Arlington	$1252.9 mil	6,700

I think it is worth asking for each of these cases what ridership would be like with a different mode, such as regional rail. I'd suspect OL to Reading would perform very similarly to regional-rail, for example.

Am i missing something, Are you telling me extending the Blue Line to Salem (assuming South Salem since a tunnel would cost a fortune) would only cost around $1.2B?!! Why the F hasn’t that been done if it’s that cheap.


Also after reading this convo it’s clear that if the NSRL isn’t to be built any time soon the Blue Orange and Red lines should be extended out to 128. Of course that’s easier in some spots than others (Blue would be a massive undertaking to get from Salem to say the NS Mall) where as the Red would be quite simple

 

[TheRatmeister]

Am i missing something, Are you telling me extending the Blue Line to Salem (assuming South Salem since a tunnel would cost a fortune) would only cost around $1.2B?!! Why the F hasn’t that been done if it’s that cheap.


Also after reading this convo it’s clear that if the NSRL isn’t to be built any time soon the Blue Orange and Red lines should be extended out to 128. Of course that’s easier in some spots than others (Blue would be a massive undertaking to get from Salem to say the NS Mall) where as the Red would be quite simple

Red would absolutely not be simple. Any elevated or surface alignment will not fly, (This is Lexington after all) so it will need to be tunneled. Maybe cut and cover is possible in some places, but the Minuteman Trail is hardly an ideal construction site. (Nor is the center of Lexington) All of these mean massive costs, which even with that 2003 estimate (Which I strongly suspect has underestimated across the board) end up being more than double any other considered project while bringing in even fewer riders than projects like OL to Reading, something I already consider to be... questionable, value-wise. This is not surprising. These stations would be used mostly by commuters, and without some pretty extreme densification in the 4th richest town in the state, there will not be significant local demand and they will never pay for themselves and only be a financial drain on the system.

 

[Riverside]

Automated light metro like the Montréal REM is a much better solution for the Blue Line than any sort of light rail conversion.

I’m intrigued. Can you elaborate?

 

[Teban54]

Red would absolutely not be simple. Any elevated or surface alignment will not fly, (This is Lexington after all) so it will need to be tunneled. Maybe cut and cover is possible in some places, but the Minuteman Trail is hardly an ideal construction site. (Nor is the center of Lexington) All of these mean massive costs, which even with that 2003 estimate (Which I strongly suspect has underestimated across the board) end up being more than double any other considered project while bringing in even fewer riders than projects like OL to Reading, something I already consider to be... questionable, value-wise. This is not surprising. These stations would be used mostly by commuters, and without some pretty extreme densification in the 4th richest town in the state, there will not be significant local demand and they will never pay for themselves and only be a financial drain on the system.

Isn't the point of rail trails to preserve the ROW for future transit or mainline rail reactivation? And there have been success stories in converting rail trails back to transit use: DC's Purple Line. Here's a recent discussion about it.

Obviously, whether it applies to Lexington is another question, but there's hope if they really want it (and Lexington was supportive the last time Red Line was to be extended).

 

[Badusername]

I’m intrigued. Can you elaborate?

This is mostly in response to ideas for Blue Line LRV conversion, which would be very expensive and result in less capacity. The perceived benefit of converting to light rail would be lower expansion costs for more branching, but as GLX shows light rail extensions can also be extremely expensive.

The benefit of automated light metro is that it increases capacity without requiring station expansion, major track work, or electrical modifications. All that is required is signaling improvements to allow for autonomous operation and platform screen doors (or sensors on the track to detect obstacles like Vancouver Skytrain, but platform screen doors are much better for reliability).

The blue line being the shortest line makes it the best trial candidate for this technology. The <2 minutes headways that automatic signaling can support means that branch extensions can be built without major service impacts in the core. Stations are often the most expensive part of extensions. With automated light metro new branch stations could be built to support shorter trains without a major capacity hit because the shorter trains can run so frequently. This would need to be communicated at the trunk platforms so riders know which doors to board at for incoming trains. Montreal REM operates 1/2 length trains off peak and communicates that with displays above the platform screen doors.

Finally, there are massive long term operational savings by not having drivers. This could also allow for 24/7 service on the line. The capital cost for upgraded signals and platform screen doors would probably be about the same as platform or track rebuilds necessary for LRV operation, but there are significant savings long term by using automated light metro and it’s a better, more frequent service.

 

[Teban54]

This is mostly in response to ideas for Blue Line LRV conversion, which would be very expensive and result in less capacity. The perceived benefit of converting to light rail would be lower expansion costs for more branching, but as GLX shows light rail extensions can also be extremely expensive.

The benefit of automated light metro is that it increases capacity without requiring station expansion, major track work, or electrical modifications. All that is required is signaling improvements to allow for autonomous operation and platform screen doors (or sensors on the track to detect obstacles like Vancouver Skytrain, but platform screen doors are much better for reliability).

The blue line being the shortest line makes it the best trial candidate for this technology. The <2 minutes headways that automatic signaling can support means that branch extensions can be built without major service impacts in the core. Stations are often the most expensive part of extensions. With automated light metro new branch stations could be built to support shorter trains without a major capacity hit because the shorter trains can run so frequently. This would need to be communicated at the trunk platforms so riders know which doors to board at for incoming trains. Montreal REM operates 1/2 length trains off peak and communicates that with displays above the platform screen doors.

Finally, there are massive long term operational savings by not having drivers. This could also allow for 24/7 service on the line. The capital cost for upgraded signals and platform screen doors would probably be about the same as platform or track rebuilds necessary for LRV operation, but there are significant savings long term by using automated light metro and it’s a better, more frequent service.

Interesting! However, I'm not sure if the calculus changes if the Blue Line is extended to Lynn and even Salem, given the insane ridership boost projected from these extensions.

Also, what branches do you imagine the Blue Line may have? A very popular proposal among crayon maps is a branch from Airport to Chelsea, but I don't think it's worth cutting capacity to Lynn permanently in half. In a far future, you can imagine a branch to the west to Watertown vs Auburndale, but that's likely in God Mode territory and shouldn't impact rolling stock decisions now. (I suspect that kind of branching is also feasible for conventional heavy rail, like the Red Line is doing.)

 

[737900er]

God-mode transit pitch of the day:

Fully automate the Blue Line with 4 minute frequencies to Lynn/Salem and Orange-length trains. Build a branch that serves the Logan terminals with shorter trains every 4 minutes.

 

[Riverside]

Very interesting! I admit I've mostly seen the automated aspect of the REM as gadgetbahn, but you make a compelling case. I'm particularly intrigued by 24/7 operation -- I think there is an unusually acute need for that on the Blue Line between downtown and Airport, where I think overnight service could make a strong impact.

I do agree, however, that the calculus changes if there is an extension to Lynn.

 

[Badusername]

Very interesting! I admit I've mostly seen the automated aspect of the REM as gadgetbahn, but you make a compelling case. I'm particularly intrigued by 24/7 operation -- I think there is an unusually acute need for that on the Blue Line between downtown and Airport, where I think overnight service could make a strong impact.

I do agree, however, that the calculus changes if there is an extension to Lynn.

Yes Lynn would need full length trains to handle CR transfers. South Station > Airport terminals > Chelsea > OL should be its own line anyway, I’m just making the case that an LRV BL conversion and branching is not a good investment.

I don’t see REM as a gadgetbahn, it uses standard rolling stock and propulsion methods with enhanced signaling. It was built at a cost per mile much less than GLX. The benefits of platform screen doors are immense and well worth the investment: passenger safety, system up-time (no massive delays due to person under train events), track cleanliness (no third rail fires or rail damage due to track litter), and climate controlled stations. To bring this back to the thread topic, I think it would be a mistake if the MGH BL station is not built with or provisioned for future platform screen doors.

 

[Riverside]

Yes Lynn would need full length trains to handle CR transfers. South Station > Airport terminals > Chelsea > OL should be its own line anyway, I’m just making the case that an LRV BL conversion and branching is not a good investment.

I don’t see REM as a gadgetbahn, it uses standard rolling stock and propulsion methods with enhanced signaling. It was built at a cost per mile much less than GLX. The benefits of platform screen doors are immense and well worth the investment: passenger safety, system up-time (no massive delays due to person under train events), track cleanliness (no third rail fires or rail damage due to track litter), and climate controlled stations. To bring this back to the thread topic, I think it would be a mistake if the MGH BL station is not built with or provisioned for future platform screen doors.

Oh yeah to be clear I haven’t seen REM as a gadgetbahn overall, just the automatic aspect. But you’ve presented a compelling argument!

 

[Tallguy]

Red would absolutely not be simple. Any elevated or surface alignment will not fly, (This is Lexington after all) so it will need to be tunneled. Maybe cut and cover is possible in some places, but the Minuteman Trail is hardly an ideal construction site. (Nor is the center of Lexington) All of these mean massive costs, which even with that 2003 estimate (Which I strongly suspect has underestimated across the board) end up being more than double any other considered project while bringing in even fewer riders than projects like OL to Reading, something I already consider to be... questionable, value-wise. This is not surprising. These stations would be used mostly by commuters, and without some pretty extreme densification in the 4th richest town in the state, there will not be significant local demand and they will never pay for themselves and only be a financial drain on the system.

The solution is RL to Arlington Heights and a single track LRT to Bedford

 

[Teban54]

The solution is RL to Arlington Heights and a single track LRT to Bedford

Single track between Arlington Heights and Bedford means you can kiss goodbye to headways. At that point, might as well make it a bus route (i.e. boost the 62).

 

[TheRatmeister]

Single track between Arlington Heights and Bedford means you can kiss goodbye to headways. At that point, might as well make it a bus route (i.e. boost the 62).

Not really. Arlington Heights to Bedford is ~6.5 miles, so with a single timed passing at Lexington Station you could totally make it work. Assuming a 20mph average speed, which seems a bit pessimistic, single track would limit you to 10 minute headways, which I think is absolutely sufficient for the line. Provision should be made for double tracking (And potentially full conversion) going forward, especially if TOD really picks up, but it's not a necessity from the start.

 

[F-Line to Dudley]

Not really. Arlington Heights to Bedford is ~6.5 miles, so with a single timed passing at Lexington Station you could totally make it work. Assuming a 20mph average speed, which seems a bit pessimistic, single track would limit you to 10 minute headways, which I think is absolutely sufficient for the line. Provision should be made for double tracking (And potentially full conversion) going forward, especially if TOD really picks up, but it's not a necessity from the start.

Cautionary tale: The RiverLINE in New Jersey shot for a similar frequency with its single + passers setup and DLRV rolling stock, and whiffed badly on that target. It barely manages 15 minute turns, and routinely gets delayed at passing sidings.

 

[Teban54]

Not really. Arlington Heights to Bedford is ~6.5 miles, so with a single timed passing at Lexington Station you could totally make it work. Assuming a 20mph average speed, which seems a bit pessimistic, single track would limit you to 10 minute headways, which I think is absolutely sufficient for the line. Provision should be made for double tracking (And potentially full conversion) going forward, especially if TOD really picks up, but it's not a necessity from the start.

That's a very interesting thought! However, I think the point still stands that if you think Lexington lacks the demand for HRT, they might not even need LRT as compared to buses that run through streets with largely light traffic, are much less of a hassle to build and operate, and can potentially run even higher frequencies reliably if really needed.

Also, F-Line suggested above that downtown Lexington itself is a bottleneck. From a quick eyeballing of Google satellite, looks like putting 2 tracks and the trail requires you to eliminate a portion of these giant parking lots. Not saying it shouldn't be done, but I'd think that if the political challenges of doing so can be tackled, then at least some other parts of the ROW can also be double tracked.

 

[TheRatmeister]

Cautionary tale: The RiverLINE in New Jersey shot for a similar frequency with its single + passers setup and DLRV rolling stock, and whiffed badly on that target. It barely manages 15 minute turns, and routinely gets delayed at passing sidings.

While definitely worth considering, I think it's also important to consider what would be different. The River Line features pretty heavy street running in some sections, something that would not be needed for an Arlington-Bedford route. It would also only be around 1/5 the length of the River Line, again good for reliability.

 

[ceo]

Isn't the point of rail trails to preserve the ROW for future transit or mainline rail reactivation? And there have been success stories in converting rail trails back to transit use: DC's Purple Line. Here's a recent discussion about it.

Obviously, whether it applies to Lexington is another question, but there's hope if they really want it (and Lexington was supportive the last time Red Line was to be extended).

Last time was before the Minuteman Bikeway was built, however. Before that, you might have gotten away with a surface line partially in trench, but these days nobody in Lexington is going to want to trade the MMB for the Red Line. (I grew up there.) So it's all-tunnel or nothing. I've never thought the idea made sense in the first place; the population density just isn't there to support it.

 

[jklo]

Last time was before the Minuteman Bikeway was built, however. Before that, you might have gotten away with a surface line partially in trench, but these days nobody in Lexington is going to want to trade the MMB for the Red Line. (I grew up there.) So it's all-tunnel or nothing. I've never thought the idea made sense in the first place; the population density just isn't there to support it.

Totally, it needs to be a tunnel.

The idea is that maybe eventually the density will fill in at some point... and also P&R at Burlington. It has to be all or nothing too because Arlington doesn't want the P&Rers.

 

[bigeman312]

Isn't the point of rail trails to preserve the ROW for future transit or mainline rail reactivation? And there have been success stories in converting rail trails back to transit use: DC's Purple Line. Here's a recent discussion about it.

Obviously, whether it applies to Lexington is another question, but there's hope if they really want it (and Lexington was supportive the last time Red Line was to be extended).

I would argue the point of a rail trail is for walking, cycling, and other micro-mobile activities, providing a scenic, safe, and quiet way for people to enjoy the outdoors.

The preservation of the ROW for future transit use is an ancillary benefit that is sometimes dwarfed by the primary point stated above. In the case of the Minuteman, the primary point of the rail trail is very, very important and beloved by local residents.

 

[Charlie_mta]

The preservation of the ROW for future transit use is an ancillary benefit that is sometimes dwarfed by the primary point stated above. In the case of the Minuteman, the primary point of the rail trail is very, very important and beloved by local residents.

There is no way the Minuteman trail would ever be converted to transit, either rail or BRT. Any transit will need to be tunneled under the trail, OR in a God Mode pitch, the trail remain in place with elevated rail over it, which is obviously a non-starter in Lexington and Arlington.