MBTA Red Line / Blue Line Connector

[RandomWalk]

I am of the belief that inside of 128 should be designated as a transit zone. That designation should be set up to enable short circuiting some of the delay tactics on the principle that living inside of 128 means you are ok with prioritizing transit.

 

[Teban54]

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'll note that the PMT had GLX to West Medford at $659.6 mil (2003, or $1.10 bil in 2023) and Red-Blue at $174.6 million (2003, or $291.6 mil in 2023). GLX eventually cost $2.28 billion, and the latest estimate for Red-Blue is $850 million. The estimates are probably way too low even after accounting for inflation.

You are really quoting 30+ yr old figures? Really?

These are the most recent figures we have. And the burden of proof is on you since you were the one that suggested BLX-Lynn is more expensive and less useful than OLX-Reading, OLX-West Roxbury and RLX-Arlington. Perhaps you have some figures yourself to support these claims?

 

[bigeman312]

My point wasn't really about 128 per say (yes it extends further away from Boston than a reasonable cutoff).

It was about fare equity when you are providing regional rail to a location in lieu of rapid transit, even though the rapid transit is more than justified by total population and population density (more justified than than it is to other areas already served).

In the inside 15 miles ring from Boston Proper zone, Lynn and Arlington stand out as communities that deserve rapid transit rail service (population densities 9.5 and 9 per sq. mile respectively), more so that Quincy or Newton (population densities 6.5 and 4.5 per sq. mile).

I again agree with your sentiment, but disagree with the details you provide.

Here is a map of Quincy's census tracts by population density. Apologies for the quality. I outlined Quincy in maroon and added red stars where the T stations are:

10,000+ per sq mile is a good, loose starting point for "urban" or "deserve rapid transit" per this discussion. You'll notice that all of the relavent census tracts have a density per sq mile of 5k-10k or 10k+. The only reason Quincy comes in with a 6.5k per square mile density is becuase much of the Blue Hills Reservation lies within municipal limits, which I'm sure we can agree has nothing to do with assessing how much a neighborhood miles away deserves transit.

Here is Arlington:

You'll notice the relevant census tracts in Arlington have basically the same density as the relevant census tracts in Quincy. Really, the only difference is Blue Hills. In fact, if you remove the area west of I-93 in Quincy, which is mostly the state park and has none of the walksheds of the transit stations, the remainder of Quincy has a population density of about 9k/sq mile, very very similar to Arlington.

 

[JeffDowntown]

I again agree with your sentiment, but disagree with the details you provide.

Here is a map of Quincy's census tracts by population density. Apologies for the quality. I outlined Quincy in maroon and added red stars where the T stations are:

View attachment 44747

10,000+ per sq mile is a good, loose starting point for "urban" or "deserve rapid transit" per this discussion. You'll notice that all of the relavent census tracts have a density per sq mile of 5k-10k or 10k+. The only reason Quincy comes in with a 6.5k per square mile density is becuase much of the Blue Hills Reservation lies within municipal limits, which I'm sure we can agree has nothing to do with assessing how much a neighborhood miles away deserves transit.

Here is Arlington:

View attachment 44748

You'll notice the relevant census tracts in Arlington have basically the same density as the relevant census tracts in Quincy. Really, the only difference is Blue Hills. In fact, if you remove the area west of I-93 in Quincy, which is mostly the state park and has none of the walksheds of the transit stations, the remainder of Quincy has a population density of about 9k/sq mile, very very similar to Arlington.

OK,. But Lynn has an even bigger land carveout for Lynn Woods than Quincy has for Blue Hills. 30% of the land area of Lynn is consumed by Lynn Woods (3.5 sq. miles of 10.7 total), so the 9.5/sq. mile is probably more like 14/sq. mile for Lynn. Well over your urbanization threshold.

 

[Delvin4519]

OK,. But Lynn has an even bigger land carveout for Lynn Woods than Quincy has for Blue Hills. 30% of the land area of Lynn is consumed by Lynn Woods (3.5 sq. miles of 10.7 total), so the 9.5/sq. mile is probably more like 14/sq. mile for Lynn. Well over your urbanization threshold.

Municpial, county, and state borders are completely arbitrary and have zero relation to actual urbanization of the region. This is why I use this map of Boston with data from https://ghsl.jrc.ec.europa.eu/visualisation.php# .

Other tools to get more specific regions here and here.

 

[bigeman312]

OK,. But Lynn has an even bigger land carveout for Lynn Woods than Quincy has for Blue Hills. 30% of the land area of Lynn is consumed by Lynn Woods (3.5 sq. miles of 10.7 total), so the 9.5/sq. mile is probably more like 14/sq. mile for Lynn. Well over your urbanization threshold.

You’ll notice there is no disagreement from me that Lynn makes sense for rapid transit.

But I disagree with your assessment that “Arlington stands out as a community more deserving of rapid transit than Quincy.”

 

[Teban54]

Municpial, county, and state borders are completely arbitrary and have zero relation to actual urbanization of the region.

While this is true in a present-day snapshot of how population density is like at the moment (the current discussion), in the long run, municipalities do matter. They decide on zoning laws, construction of new housing, and favorability towards transit, pedestrians, bikes etc - and all these factors not only influence their future population density and their dependence on transit, but also feasibility of getting transit there in the first place.

 

[Delvin4519]

While this is true in a present-day snapshot of how population density is like at the moment (the current discussion), in the long run, municipalities do matter. They decide on zoning laws, construction of new housing, and favorability towards transit, pedestrians, bikes etc - and all these factors not only influence their future population density and their dependence on transit, but also feasibility of getting transit there in the first place.

Yea. I was trying to point out the original calculations for population density of Lynn and Quincy was incorrectly including the forested parts of Lynn and Quincy, which skews the numbers significantly and makes the population density values meaningless. Hence the proper calculation is to utilize the map of urbanization to find the actual population density of the inhabited portions of the municipalities.

 

[JeffDowntown]

You’ll notice there is no disagreement from me that Lynn makes sense for rapid transit.

But I disagree with your assessment that “Arlington stands out as a community more deserving of rapid transit than Quincy.”

I take your point about Quincy, and particularly the density around where the Red Line runs.

 

[bigpicture7]

So, ahem, about that tunnel under Cambridge Street to Charles/MGH?

 

[HenryAlan]

OK,. But Lynn has an even bigger land carveout for Lynn Woods than Quincy has for Blue Hills. 30% of the land area of Lynn is consumed by Lynn Woods (3.5 sq. miles of 10.7 total), so the 9.5/sq. mile is probably more like 14/sq. mile for Lynn. Well over your urbanization threshold.

And if you look at the actual rail corridor, the density increases significantly further. See the link below if you want to look at this on a tract level detail. I randomly picked a few tracts next to the ROW, and came up with around 25K per square mile.

2020 Census Demographic Data Map Viewer

 

[Vagabond]

Was struggling a little bit to see where all these proposed connections fit together. Looks like the current garage door turns into the stairway/tunnel?

EDIT: PS - Count me in for that Parquet floor!

 

[ceo]

Was struggling a little bit to see where all these proposed connections fit together. Looks like the current garage door turns into the stairway/tunnel?

Yep. That was included in the redesign of Charles/MGH as a place to tie in the Blue Line connection.

 

[cooper]

Was struggling a little bit to see where all these proposed connections fit together. Looks like the current garage door turns into the stairway/tunnel?

View attachment 44785

Looks sleek in the drawing, but they're obviously going to have to reconfigure this pillar just outside the garage door to support the red line

 

[C-Town_Jeff]

Looks sleek in the drawing, but they're obviously going to have to reconfigure this pillar just outside the garage door to support the red line

In the rendering the bottom 7/8ths of it is just missing.

 

[RandomWalk]

Given that it’s underneath a joint between trusses, I think that might need some revision.

 

[Equilibria]

I recall this was designed to coincide with a rehab on the viaduct down into the Red Line tunnel, so maybe they could replace/redesign the support through that work.

 

[Stlin]

A few things. Firstly, while it looks like it's directly in line with the door and the future Blue Line Access, keep in mind that the red line curves as it comes through Charles MGH, so neither the pier nor headhouse is directly in line with Cambridge Street and the future Blue Line Platform. Therefore, any blue line access will necessarily be on a skew relative to the existing headhouse.

Secondly, while there is an ongoing Longfellow Approach Viaduct rehab project, the 2019 conceptual plan for that explicitly disclaimed any notion of modifying the piers.

However, it's important to note that the 2021 plan that the renders are based on post dates the 2019 Longfellow Approach presentation. Note that the 2021 conceptual plan does call for the elimination of that pier, with stairs immediately underneath it. It also clearly shows replacement structure, two rather thin but still hefty columns, one outside and one between the stairs and escalators. That doesn't appear to be shown in the renders, but is shown in the plans.

The approach project haven't seen any board updates since 2019, despite construction set to start in 2025, but there's nothing publically available to say what will actually happen to pier 6 as yet - I do hope they'll build it as per the 2021 concept.

 

[NoShJFK]

Can someone who knows the details better tell me if extending the blue line to Vinnin Square area is possible just by having it go along the CR tracks?

 

[bakgwailo]

Can someone who knows the details better tell me if extending the blue line to Vinnin Square area is possible just by having it go along the CR tracks?

As far as I know, the issue isn't the CR row up to Salem, it's getting the blue line over into the row by point of pines (or before).