Ashmont-Mattapan Trolley Line Discussion

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Re: Ashmont-Mattapan Trolley Line Discussion

Postby Bramdeisroberts » Wed Jul 13, 2016 3:55 pm

F-line to Dudley via Park wrote:Ta-da? If Milton were willing to part with its boutique intermediate stops full Red conversion project-managed well is pretty low-hanging fruit, no?


And the PCC's can be freed up to run on the new Blue Hill Ave line!
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby MBTA3247 » Wed Jul 13, 2016 7:20 pm

F-line to Dudley via Park wrote:-- Mattapan -- This one can be done with fairly minimal modification and ample recycling of existing structures. Take the small island platform between Tracks 2 & 3 and extend it both directions to 6-car Red Line length, bumper posts at the end of the platform. Drop the trackbed to achieve the proper platform height.

I don't think that will work as well or as cheaply as you think it will. The platforms have no foundations, so dropping the tracks while leaving them intact would require careful digging around the platforms plus undermining them at the edges to put in the wall of the track pit. It's probably easier to just rip up the existing platforms and put in a new high-level island between tracks 1 and 2 (after spreading them farther apart).
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby BandA » Wed Jul 13, 2016 9:53 pm

Instead of using 3rd rail, have the "subway cars" switch from 3rd rail to catenary. Then you can keep crossings. Put in high-level platforms, but since all trains stop at all stations, allow people to cross tracks where necessary.

Or keep the PCC cars or PCC-IIs.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby F-line to Dudley via Park » Thu Jul 14, 2016 6:32 am

Because that would be a loser on value-for-money. Dual-power works for the Blue Line because you're talking a pre-existing setup, only ~95 cars that have to be ordered with dual power inputs and associated electronics, and a roughly 60/40 split of overhead vs. third rail route miles making conversion to one uniform power source money wasted on perfectionism for perfectionism's sake. It'll always cost less to order cars with shoes and pantographs than it will to convert everything to third rail or everything to overhead. Red's different. It's ~25 route miles of pre-existing third rail (way more if lumping in all that non-revenue third rail) and less than 2.5 new route miles being tacked on for Mattapan. Plus ~220 cars you'd have to retrofit and order with pantographs for each vehicle procurement forevermore. Those are lousy ratios for cost recovery, complete opposite from Blue's ratios. Unlike Blue you would amortize the cost way better here paying the one-time capital charge to eliminate the two grade crossings (which aren't big costs in absolute terms; there are cycled rehab jobs of pre-existing rail bridges that cost more than each of these builds).


Also, the safety issue of pedestrian crossings on heavy rail is irrelevant to what the real issues are with keeping these crossings: traffic management. When you project up from High Speed Line headways on 1-car trolleys to Ashmont Branch headways on 6-car heavy rail vehicles it would wreck traffic queues on Central Ave. to have the crossing blocked by a 6-car train from one direction every 3-4 minutes at rush. The associated slow zone and variability in trains clearing the crossing would then stress brittle Red OTP through Downtown and out to Alewife, introducing too much bunching and too many schedule corrections for maintaining the orderly Ashmont-Braintree-Ashmont-Braintree alternating progression through Downtown. Traffic management in the neighborhood and on Red out to Alewife makes the up/down decision on eliminating the crossings way, way before you debate the safety vs. convenience footnotes. And does it on raw numbers you can easily crunch with some traffic counts and a calculator. Plus, if traffic counts force you to mandatorily eliminate Central Ave. then closing the insurance liability loophole carries through to mandatory elimination of Capen likewise on dollars and sense you can tangibly add up vs. the relatively low one-time cost of building an overpass there.

Recall that the Orange Line Reading extension in the 70's was going to power-switch to overhead and retain some of the crossings. But Orange was also going to be traffic-managed through Downtown by the express track extended north to Oak Grove and by headway-throttling short-turns at other times of day when demand to the north 'burbs tailed off. That Orange plan had a built-in solve for street and subway schedule traffic management. Ashmont Branch extension to Mattapan has no such throttling capability, and that's the fundamental difference preventing direct comparison with other past or proposed heavy rail grade crossing examples. You'll never reach a point where safety/convenience details of heavy rail crossings existing at all becomes a primary debate topic, because traffic management considerations will have made the up/down decision long beforehand. It's either: A) eliminate the crossings as a necessity for running thru headways to downtown, or B) don't eliminate the crossings and keep the line as a trolley shuttle forever.


If it comes down to splitting hairs about spending a not-at-all-expensive $40M lump sum on a two-fer of relatively straightforward up-and-over earth moving jobs, then you long ago made up your mind that conversion from trolley to heavy rail isn't worth the money period and eliminated that option from consideration. The grade crossing issue is an argument purely in the abstract. No real-world debate about conversion is ever going to snag itself on that minor a detail because the value proposition--pro or con--will have previously overpowered it on far much bigger considerations.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby typesix » Mon Jul 25, 2016 10:38 am

Article on Mattapan transit options and one user complaint about the trolley line:

http://www.bostonglobe.com/metro/2016/07/25/mattapan-transportation-island-can-fixed/TbVKEONzFvDxroVe21iC8K/story.html
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby Disney Guy » Thu Jul 28, 2016 12:47 pm

If the Mattapan line were converted to rapid transit, then for how many months would it be shut down for construction?

What would the service be like? Would every Ashmont train go to Mattapan?

Looks to me like it would be better keeping things more or less the way they are but adding another car during the off hours to get the service less than 15 minutes between cars. Also synchronizing the cars with the Red Line trains particularly during evenings and weekends.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby ExCon90 » Thu Jul 28, 2016 2:24 pm

Didn't they have at one time a holding light on the trolley platform at Ashmont to instruct an operator to remain at the platform if a Red Line arrival was imminent, and is that still the practice? In any situation like that it's more than irritating to get to the connecting platform just in time to see a car departing, with a long wait until the next one.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby Disney Guy » Sat Jul 30, 2016 8:53 am

(in the article whose link is above) "A slow trolley to connect at Ashmont station. Glacial paced buses."
There is a common thread to these two complaints, all those boutique stops, where as soon as the bus (or trolley) starts up, you hear the "ding" for another stop request.

The Mattapan-Ashmont line followed an existing rail line as opposed to being designed for up to date (for its time) population travel destinations. Since the line's inception, demographics have changed. Now there is a dilemma. To get from Mattapan to Longwood (medical area) you have to choose between going around three sides of a square to your destination using rail, or just the fourth side using the bus. Circuitous routes to employment away from Boston's downtown core affect many folks, not just those from Mattapan.

If you ask me, a complete in-street light rail line is an amusement ride. Private right of way light rail is real mass transit. Witness the B (Boston College) line's glacial behavior. Given the construction costs and operational difficulties, I could not envision a median rail line up Blue Hill Ave.

There are a variety of low cost methods to speed up bus service but they are beyond the scope of this forum.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby F-line to Dudley via Park » Sat Jul 30, 2016 10:53 am

Disney Guy wrote:If the Mattapan line were converted to rapid transit, then for how many months would it be shut down for construction?

What would the service be like? Would every Ashmont train go to Mattapan?

Looks to me like it would be better keeping things more or less the way they are but adding another car during the off hours to get the service less than 15 minutes between cars. Also synchronizing the cars with the Red Line trains particularly during evenings and weekends.


Every Ashmont train would continue to Milton and Mattapan stations on the same headway. Codman would continue to be the branch's yard (wouldn't be a need for anything other than a pocket track for OOS trains at Mattapan). Only additional equipment needed would be an extra headway re-spacing set or two to make sure service levels are unchanged.


Given typical T construction pace and contractor supervision (or lackthereof), probably a well-padded 2 years. But that's at inefficient T pace, not real-world possibles.


This stuff can happen while the trolleys are still running uninterrupted at all stops:
-- Any upgrades to the trunk electrical feed.
-- Basic track work like replacing the flimsy old trolley track with heavier/smoother rail up-to-spec for the rest of the system, tie replacement, cable trenching for the RL signal system and third rail conduits.
-- At future Milton Red Line station they can temporarily close the Riverwalk path between the Milton trolley platforms and the former rail bridge to the ex-mill, and re-align the outbound track right after the mini-high by swining it out onto the path footprint to create space in the middle for the new island platform. Would not affect the old station.
-- Pour the foundation for the new Milton platform.
-- Installation of security fencing.
-- Road construction along Eliot St. in prep for the new station (bus turnouts, clearing out widening space up to the ROW retaining wall.
-- Prelim site prep around Mattapan station (any touches to the busway, pre-prep of the station building for expansion into a prepayment lobby). Get the stuff that'll have any impacts on the temp shuttle buses out of the way.
-- Surveying and site prep around the to-be-constructed grade separations.



This can only happen during the shutdown:
-- Bridge construction over Central Ave. and Capen St. + demolition of trolley platforms.
-- Embankment building and retaining wall construction around Central Ave. and Capen St. overpass inclines.
-- Retaining wall work around Eliot St. (will probably need to cap it off a couple feet in places so Eliot can get its bus turnouts).
-- Platform finish and headhouse construction at Milton. At least enough to make the prepayment area and platform operable for the trains, even if rest of the station takes longer to finish.
-- Demolition of Mattapan Yard, pouring of new platforms, construction of headhouse wrap-around to new stub-end platforms. Again...at least enough to make prepayment and platforms operable for re-start of service while rest of station is work-in-progress.
-- Demolition of remaining trolley platforms. Realign outbound track through old Milton trolley platform so the spreading around the new island platform is gentler.
-- Infill of remaining security fence installations (esp. around old trolley station entrances).
-- Track work: connect mainline track at Ashmont; add wye track from Codman Yard pointing in Mattapan direction; lay new Mattapan Station tracks + pocket storage track; install third rail; install ATO signal mounts; install any switches and crossovers.
-- Test trains.


This can happen post-restart:
-- Finishing touches on Milton and Mattapan Stations.
-- Reconstruction of cannibalized portion of Riverwalk @ Milton station (could re-do it closer to riverbank with boardwalk, could do cycle track on side of Eliot St. with overpass + ramp back down to track level over west end of Milton station, could do something else entirely).
-- Reconstruction of Riverwalk alongside Central Ave. overpass (tight squeeze but should slide around retaining wall; assume there'll be some mop-up work before path reopens).




That's pretty much it. Managed well you could probably do it in a 12-18 month shutdown if they used their pre-shutdown resources wisely to clear away as much work as possible. Then so long as all the concrete pouring of retaining walls, bridge abutments, and platform foundations got done before ground freeze they should be able to work through winter on those critical structures. If stuff doesn't fall behind schedule it's mainly the stitch-together around the new overpasses, having complete Milton and Mattapan platforms, and getting some sort of barebones prepayment areas operational (even if well incomplete) that are the hurdles to clear for a fast reconnection and re-start. Whether that can hit under 2 years or over is entirely dependent on quality of project management and whether the contractors can work on-time. Other than that there really isn't a huge spread of tasks beyond the single-point construction zones at: 1) Milton Station, 2) Central Ave. overpass, 3) Capen St. overpass, 4) Mattapan station. The track reconnection and testing goes fast if all the cable trenching and rail replacement got done way in advance pre-shutdown.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby F-line to Dudley via Park » Fri Aug 12, 2016 10:25 am

Pics from a trip to Lower Mills on a scorching hot lunch hour yesterday...Pt. 1:
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Clearing work has begun for the path extension past Central Ave. 500 ft. now cleared, 1500 ft. to go before reaching the Valley Rd. platforms. Crews returned from lunch to push more dirt around few mins. after I snapped this pic.
Image


Taken back where the old Lower Mills freight siding forked off across the bridge. The retaining wall for the trolley incline is starting to get a little crumbly, but couple nice murals have been painted on it around the tallest point.
Image


At the mural in the last pic. This is MUCH closer than it looks...at most 4 ft. from the trucks. Highly underrated 'fanning spot.
Image


Looking towards Central Ave. from the mural.
Image
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby F-line to Dudley via Park » Fri Aug 12, 2016 10:32 am

Pics from a trip to Lower Mills on a scorching hot lunch hour yesterday...Pt. 2:
-------------------------

This is what the mills freight siding bridge looks like now.
Image


View from the bridge. Needed to soak in what very weak breeze was coming off the water, because it was broiling out! Very quiet spot. Look to the right, see the trolley incline + murals. Look to the left, see the courtyard at the Lower Mills development.
Image


Central Ave., standing on the gravel for the path extension and looking back at the end of the current path. 3268 is climbing the grade of the mini-incline heading towards Milton station. Why did they prop the trolleys up on this insignificant rump of an incline while keeping the freight track ground-level??? The riverbank is so far below the street this isn't a flood-prone spot.
Image


3268, air conditioner blasting. I noticed a concerning amount of rust creeping in around 3087's door frame, and another unit that's starting to show moderate amounts of roof corrosion. Time for a fleet re-painting???
Image
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby MBTA3247 » Fri Aug 12, 2016 11:23 am

F-line to Dudley via Park wrote:Why did they prop the trolleys up on this insignificant rump of an incline while keeping the freight track ground-level???

A minor cost-saving measure. They had to cut down the hillside when they built the trolley line, and apparently saw no reason to cut it down to the level of the original track.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby WatertownCarBarn » Sat Aug 13, 2016 8:43 am

Great pictures. I bike the trail frequently and enjoy the PCC views immensely, particularly on the rise.
A little OT: Notice on the mills freight siding bridge a tiny bit of pooled water; and we haven't had much rain. In a normal season the bridge almost always has pooled water on it. Can't imagine the wood will last long.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby doublebell » Sat Aug 13, 2016 12:45 pm

You can see the gate bounce up and down.
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Re: Ashmont-Mattapan Trolley Line Discussion

Postby typesix » Fri Oct 21, 2016 2:56 pm

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