How much would it cost to extend the Orange line out there as originally planned? The bottlenecks are there because the OL takes up 3 tracks, and if existing service is going to go through the Lowell line then why not? With Lowell turned to OL then the Eastern Route is the only thing going through the Sullivan bottleneck and frequent dmu Lynn/Salem would be much easier.
$$$$$$.
It's the grade crossings. 15 of them, nearly all abutting the station stops. Some of them are very busy crossings, too, like Greenwood which has to have a staffed crossing tender all day long. They would have to build Malden Ctr.-esque elevated stations or Oak Grove-esque pits at every single one of the existing stops. With all the NIMBY concern-trolling that would ensue.
In the 1970's when they were first considering this the plan was to eliminate only the worst of the crossings, switch the OL to overhead power at Oak Grove like the Blue Line, and run to at-grade stations for the platforms that immediately abutted reasonable-traffic crossings. That's not going to fly today with an HRT line, so they'd have little choice but to go for total elimination.
That moves it way, way lower than the W. Roxbury extension and most others on the priority pile because of the added expense. The only thing that would up the priority is the N-S Link and electrification of the inside-128 commuter rail network. That's a complete waste of time and money for the Reading Line because of how much of the route would have to have entirely duplicate electrification, and how little extra track capacity it has to offer Link-originating traffic for that electrification expense. It becomes the northside's odd man out. And by that point however many decades in the future the northside will be a much different place with Malden-like density pushing further and further out to Reading, so the time will be ripe to go whole-hog Orange with it justifying the cost.
What would the T have to do to switch over the Lowell line to heavy rail? If they're worried about cars then they can put an option on the orders they're already making for the orange/red and buy more when the time comes. Could they re-use most of the cr trackage and row, or would this be more complicated then that?
The Lowell ROW is 4-track width most of the way to Anderson. For the most part it would be much like GLX now where you're not doing any additional land-taking whatsoever to lay the tracks. The pinch points are:
-- The Route 16 and Mystic River bridges. Those were always 2-track old stone arches. When GLX was eventually going to continue to West Medford both of these bridges were due to be expanded to 4 tracks, possibly with the historic arches being faux-extended with conjoined new structures. That was studied and can absolutely happen.
-- West Medford grade crossings. Route 60 is one of the worst crossings on the system. GLX was going to stop short of it on opposite side of the street from the CR platform, and Canal St. crossing probably would've been closed. Rapid transit or no, escalating CR and Downeaster traffic alone will render this one intolerable. Other than Eastern Ave. and Everett Ave. in Chelsea on the Eastern Route this is the #1 highest-priority crossing elimination on the system. To do it they'll probably have to start a steep incline off the Mystic bridge on the 1400 ft. towards Route 60, use a trackbed drop + road bridge as half-and-half of the Canal St. separation, go under Route 60, and drop the station into a deep cut. Then incline-up at an easy, gradual grade en route to Wedgemere.
Expensive, very disruptive during construction...and there's growing consensus in the neighborhood that the end result would be worth the few years of pain. If they proceed with this the smart thing to do is make the cut 4-track width, even if the 16/Mystic bridges are untouched and there are no immediate plans to use the other berths. One-and-done. The West Medford station cut will work as a 4-tracker if they put retaining walls up to the Playstead Rd. sidewalk a la Somerville Ave. @ Porter station. And maybe redevelop the Rite Aid parcel with something taller but a few feet further offset from the station. If GLX comes out here, just outright flip the CR station to the other side. You will see behind the station that the line goes 3-track for a short distance. A lot of extinct freight used to be on the couple blocks on either side of W. Medford.
-- Winchester Ctr. Viaduct. Done in a package with the Wedgemere grade separation in the 50's (grade crossings used to be straight down the middle of the rotary). If the station gets nuked there's probably room for 4 tracks on either side of the rotary overpass, but it would be a very tough sell to widen the overpass and obscure nearly the entire rotary, much less put a rapid transit station on top of it. If this is a blocker with the town you may need to leave the RR up on the viaduct and dip down for 1500 ft. of subway under Laraway Rd. and Shore Rd. with an underground station to skirt the viaduct.
My guess is this dilemma means the line ain't ever coming past West Medford unless you're dead serious about extending all the way to Anderson in one fell swoop. And that probably isn't necessary unless the N-S Link throws so much traffic down the Lowell Line and so much growth to the northside 'burbs that there's crying need for the local stops to all flip modes and for CR trains to all run express to Anderson before fanning out.
-- Individual bridge widenings the rest of way, but nothing too major.
Wedgemere: platforms currently hang off the Aberjona River and Bacon St. bridges; assuming rapid transit displaces the CR platforms must move the station stop to the other side of Bacon St. to fit 4 tracks over the bridges.
2-track bridges and overpasses needing +2 track widening: Skillings Rd. Winchester, Cross St. Winchester, Mishawum Rd. Woburn.
Current or former 3-track bridges/culverts/overpasses needing +1 track widening: Spruce St. Winchester ped underpass (culvert), Swanton St. Winchester, Montvale Ave. Woburn, Walker Pond drainage (culvert).
Unmodified overhead bridges in Woburn that need no structural mods but may need drainage ditch reconfiguration underneath to fit extra tracks around abutments: Salem St. (maybe), Olympia Ave. (maybe), Route 128 (definitely).
And that's it. You can see the rest of the ROW is wide enough to handle 4 tracks with minimal landscaping, including through the swamps. And that there's a lot of current and former freight sidings (including. a semi-abandoned yard across from Calvary Cemetery) serving up recent-origin 3- and 4-track space. Plus signal towers already spaced for at least 3. North of Winchester viaduct to Anderson the ROW preparation is consistent with the same minor cosmetic work that's been going on for a year in Somerville and Medford in prep for GLX. Take that GLX bridge, culvert, and retaining wall work ongoing...multiply by 2x as many structures and distance, and you get a pretty accurate picture of what costs would be everywhere outside of Winchester Ctr. and outside the stations. Assume that the Medford crossings are a by-2020's project driven by commuter rail and Downeaster alone (taking Reading for DMU's and moving Haverhill over might be the trigger). And assume that a +1 GLX extension that remakes the 16 + Mystic bridges is a decades-sooner project attached to or closely trailing the crossing elimination project.
Not bad at all except for solving the Winchester viaduct problem. It probably costs less to get between 16 and Anderson than it does to get from Oak Grove to Reading. Although I don't think the past- W. Med ridership really matters as much as Reading or matters at all until the N-S Link forces enough traffic up the Lowell Line and wholesale-transforms the demographics and commute patterns on all the northside inside-128 'burbs.
In the meantime if they can find an excuse to:
-- Get rid of senselessly duplicate Wedgemere with a better and more frequent bus to GLX.
-- Get rid of all-around senseless Mishawum.
-- Add a badly needed Woburn infill stop around Montvale Ave., and do a brisk W. Med.-->Winch Ctr.-->Woburn-->Anderson jaunt.
-- Move the full Haverhill thru schedule over, expand that schedule with a bigger Bradford-replacement layover yard
-- Extend the Lowell Line to Nashua with
that requisite big layover yard to increase frequencies (right now Lowell has no active layover)
That probably achieves a near- clock-facing schedule just on the push-pulls. With 15 min. frequencies at peak that don't require any supplemental DMU's. Which may be necessary if the DMU model they buy can't board from low freight-clearance platforms. The line can go on the Indigo map all the same if the peak schedules to the NH border are full enough, and if they fill in the off-peak gaps with short Anderson-turning trains of just a locomotive + couple of cars. The stop spacing here is so uniformly wide here there's no perceptible clock penalty on a push-pull vs. DMU when standard all-vehicle schedule padding is taken into account.
