Blue Line engineering question

[Leo Sullivan]

I'm too lazy to work this out, unless I have to. If the Bowdoin Loop were out of use or rebuilt out of existence, what would be the longest car usable on the Blue Line? The next most restrictive curve is probably the one just intown from State but, it doesn't seem as tight. Anyone have any information?
LS

[DelawareHudson]

I'm not sure what the curve is in degrees, but I'm thinking it's pretty tight. Isn't State the station where the cars clip the edge of the platform if they come around the curve a little too fast? IIRC, the platform is even shaved back a bit, but there are still some of the BL cars which have the telltale dent on the corner.

[apodino]

Howabout under Boston Harbor, leaving Aquarium the first part of the tunnel is curved? Does this affect anything?

[Leo Sullivan]

I dont think the part under the harbor is so much of a problem. It might effect speed but, I'm thinking about absolute clearances. Kurt spotted the new bottleneck and, that (State St) is where I was standing, looking at that curve, when I started wondering about this. There isnt much option for slewing track there, either. The proposals for long extension to the North Shore got me thinking about what kind of equipment might be acceptable, for a line to Beverly (definitely not the 0600s). Whatever they built outside, the Tunnel is still the governing factor for equipment design.
I've ridden the North Shore Line and remember that their cars were designed, first requirement, to fit on the Chicago 'El' (they fit on the Orange Line too). All those open spaces and good clearances didn't
make bigger cars possible, they still had to go round the Loop.
They did however, manage quite a lot given the restrictions, finally using articulated units. Maybe articulateds are always less demanding than changing civil engineering.
Worse yet, the East Boston Tunnel was designed for small surface cars, not elevated cars so, even getting 1912 streetcars in there was a challenge.
Too bad the Red Line doesn't poin toward Lynn.
LS

[The Collector at Court St]

IIRC, when they looked at possibly closing the Bowdoin Loop, they would only gain 4 to 6 feet in car length. They didn't feel the few feet was worth the option of losing the loop and the yard. The articulated design for the new Blue Line cars was rejected mostly due to the shop lift rebuild cost and losing the option of mismatching pairs easily in an emergency or for special reasons, like 652-635-634-653.

[Charliemta]

Leo,
"Too bad the Red Line doesn't poin toward Lynn. "

The Red Line doesn't, but the Orange line could have a branch built off of it towards Lynn. Using existing rail lines, there are two routes an Orange line branch could take:

Route A: Branch off the Orange line just north of Sullivan Square, follow the existing rail line to Chelsea and then north/northeast on that rail line, almost to the Wonderland race track, then turn northeast to the Wonderland station. At that location, the Orange line branch route would use the proposed Blue line extension route, along the old narrow guage rail ROW through Point of Pines to Lynn, and extend on to Salem.

Route B: Branch off the Orange line just north of the Edgeworth station, then join the existing rail line that runs east from Malden (parallel to Route 60). Continue on that rail line to Northgate Shopping Center in Revere, then head east/southeast, along the southern edge of the marsh land, joining the proposed Blue line extension route about 1/2 mile north of Wonderland station. At that location, the Orange line branch route would use the proposed Blue line extension route, along the old narrow guage rail ROW through Point of Pines to Lynn, and extend on to Salem.

My preference would be Route A, because it would provide a heavy rail transit line for Chelsea.

[efin98]

My preference would be Route A, because it would provide a heavy rail transit line for Chelsea.

We thank you for that :D. Unfortunately such an extention would never come to fruition because of the cost of rebuilding some of the highway overpasses, removing five grade crossings and expanding the right of way between the Grand Junction wye and Lynn. Those would be a deal killer, especially with the right of way at grade in Chelsea.

[ceo]

Option B is even more of a non-starter. Dozens of grade crossings, including at least one on Rte. 60, would require it to be buried or elevated, and Malden already has the Orange Line.

[subway2004]

Does anyone know if the yard/layup in the Bowdoin loop is still in use?

[Robert Paniagua]

Yeah, it's still being used, especially the loop. The yard after Bowdoin is sometimes used too.

[subway2004]

Yea I knew the loop was, I was refering to the yard. When is it used, only weekends? Anyone know if there is a spot to get a good look at it? This has always been a little mystery to me. Thought the tracks used to continue out to Cambridge St.... Thanks

[BC Eagle]

I had no idea there was a yard after Bowdoin. Can someone describe it?

[ckb]

Here's what the article on NEtransit has to say:

"The tunnel extends beyond the Bowdoin loop to a portal sealed since October 23, 1952, on Cambridge Street at Russell Street. The trackage is electrified and used to store disabled trains in emergencies."

I can't find another reference right away, but my understanding was that this portal connected the line to the Red Line - it was the way that the Blue line cars made their way to the old Eliot shops (located past the Harvard Sq. station towards the Harvard Stadium).

Anyone else wishes to jump in, please go ahead.

[jrc520]

yup. it lead to surface tracks, which then connected to the red line tracks. hm, ascii art may work.
Bowdin to kendall

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that's about the best I can do.

[bingdude]

There was a book: Linden On The Saugus Branch, by Eliot Paul. It was reminiscing about his childhood in Linden, somewhere in Malden, along a B&M branch.

Is that branch still there? Maybe it could be a good route to use to get to Lynn .

Having taken the Blue Line to the airport many times, I think that curve at State is the real clearance restriction and unless it is re-engineered a trip to Lynn on the Blue Line would be a long slow one.

I remember the shops at Harvard, but they were on the Cambridge side of the river. Right where the Brattle Street crosses Mem. Drive, not next to the stadium.