SM89 wrote:May I ask the obvious question: Why don't they settle on a standard car width? Why are passenger cars narrower than freight cars? I'm sure it's due to historical considerations, but I can't think of a compelling reason not to come up with a standard in this day and age. Cost shouldn't be the reason as the costs of trying to cater to both are definitely more.
It's actually not the car width that causes the issue with full-high platforms. It's car length
. Large-capacity freight cars (right down to mundane stuff like larger boxcars) have wider turning radius on their axles to accommodate their longer length, which poses a clearance problem with full-highs if there is even the slightest curve. Both the longer AND the taller cars also have more tolerance on their truck suspensions for lateral movement than your average small car or passenger car, which also leaves them more susceptible to smacking the edge of a full-high. Which can damage the platform, cause a derailment, and certainly cause injury to people on the platform or the crew on the freight train if either happens. Therefore, the only practical options for ADA platforms on a designated freight clearance route are: passing tracks, gauntlet tracks (not used unless absolutely necessary because they're a little ham-fisted to operate and carry slightly higher derailment risk), or low platforms + single-car mini-highs.
Technically if the platform is tangent to neutralize the turning radius issue of the cars...and you pass by slow enough to neutralize the lateral movement of the cars...you can slip nearly anything past a full-high. But it's operationally impractical to inch...say...an autorack past a full-high at 0.5 MPH with multiple crewmembers on the ground attending to the move. 5 MPH is probably enough to create enough lateral movement potential to hit the platform. And in some of these places not having the full-high lets the freights do 40-60 MPH, so you're wildly on the side of total impracticality trying to force it like that; at a certain point of insanity it starts totally hosing the passenger schedules to NOT compromise with a mini-high. So you only see oversize moves in full-territory for special one-offs like electrical transformer moves where they get permission from the FRA ahead of time and have extra escorts onhand to make sure it's a safe passage. Sort of like when an oversize load is transported on an interstate highway. It's not something they're at all prepared to do on a daily basis.
Only the busiest freight lines are protected as clearance routes. You only see this exception on the lines that carry a lot of heavy interstate freight (CSX to Framingham, Pan Am to Ayer and Portland, Lowell Line to Boston Sand & Gravel) or provide crucial links to yards and interchanges (Framingham-Readville, Framingham-Mansfield-Attleboro-Middleboro). For the lines that carry strictly local freight in small amounts standard-dimension cars handle 100% of the need (e.g. Old Colony Line, Eastern Route to Salem, NEC to Westwood/Stoughton, Framingham-Everett, Franklin-Milford, Fairmount Line). And some types of cars like tankers (e.g. Quincy/Braintree), and the shipping cubes on well cars proposed for Marine Terminal in Southie via Readville-Fairmount Line either fit totally within standard dimensions at their very largest size (i.e. tankers) or, in case of single-stack well cars, will safely slip clear the hollow underside of a full-high without problems. The only place on the T where there's a brewing freight clearance incompatibility is South Coast Rail on the Fall River and New Bedford branches. The Ports of FR and NB will be equipped to take oversize loads when MassPort dredges those harbors, but the passenger platforms are all going to be full-high with no passing tracks. But since when has SCR not always chosen precisely the wrongest and most counterproductive possible thing when designing that turkey?
There are the only freight clearance routes the T has to worry about. Some aren't ADA or haven't been raised yet, but stations that have to be mini-high and stations that can go full-high because of pre-existing passing tracks are listed.
-- Worcester Line: Framingham-Worcester + Amtrak, Framingham-Albany.
Stations affected: Framingham, Ashland, Southborough, Westborough, Grafton (mini-high platforms). Worcester Union Station, Springfield Union Station, Pittsfield (existing passing tracks).
-- Fitchburg Line: Wachusett-Willows Jct., Ayer.
Stations affected: Ayer, Shirley, N. Leominster (mini-highs if/when all upgraded to ADA). Fitchburg (existing passing tracks). Wachusett (to be built on turnout w/passing tracks).
-- Western Route: Lowell Jct., Andover-Portland (MBTA and Amtrak).
Stations affected: Ballardvale, Andover, Bradford, Haverhill (mini-highs). Lawrence (existing passing tracks). Plus all Downeaster stops through Old Orchard Beach.
-- Wildcat Branch: all, Wilmington-Wilmington Jct.
No stations. Salem St. a former stop still owned by T; would have to be mini-high or turnout if rebuilt.
-- NH Mainline: all, Somerville-Lowell-Concord, NH.
Stations affected: all. Anderson RTC, Lowell (existing passing tracks). All others (mini-highs or non-ADA to-be-upgraded to mini-high)
-- Franklin Line, Walpole Jct.-Readville Yard
Stations affected: Endicott, Dedham Corporate, Islington, Norwood Depot, Norwood Central, Windsor Gardens, Plimptonville (all mini-highs or future mini-highs when ADA'd). Walpole (passing track on NE leg of wye). Fairmount Line Readville platform to be relocated a couple hundred feet north when it goes full-high so the freights turn out away from the station (Franklin-side Readville platforms have no freight).
-- NEC: Mansfield Jct.-Attleboro Jct. only
Stations affected: Mansfield (mini-high), Attleboro (passing tracks). Attleboro can go full-high with no track changes. Amtrak's plans call for installing a passing track at Mansfield, so that installation would happen in tandem with full-high platforms.
-- Framingham Secondary: all
Stations affected: Foxboro (current mini-high; proposed passing track)
-- Middleboro Secondary: all, Attleboro Jct.-Middleboro Yard
Stations affected: Taunton Depot stop on South Coast Rail (proposed passing track)
-- NEC, Boston Switch in Central Falls, RI-Davisville, RI
Stations affected: Providence, T.F. Green, Wickford Jct. (existing passing tracks, including when future 2nd platforms installed @ Green/Wickford). All proposed RIDOT infill stations (to have passing tracks).
-- Eastern Route, Somerville-Everett Jct. (i.e. Everett Terminal turnout )
(No stations, too short a distance on Everett side of bridge for any possibility of stations)
That's it. The Worcester Line inside Framingham is fair game for full-highs now at the 3 Newtons, 3 Wellesleys, and 2 Naticks now that the freights have vacated Beacon Park; CSX's Everett Terminal daily produce train does not use oversize cars. The Franklin Line from Walpole to Forge Park will no longer have any freight by year's end when CSX turns the Milford Branch over to Grafton & Upton RR; Norfolk, Franklin, Forge Park now fair game for full-highs. And in many other cases there's adequate room for passing tracks should they want to pursue a full-high reconfiguration should they ever want to pursue it:
-- Framingham (room for passing track along the wye immediately behind the platform)
-- Ayer (potential for center island full-high if 4th track added on south/wye side)
-- Bradford (potential when layover yard is relocated north to shift the platforms onto layover yard space and turn 1 or both mainline tracks into freight/Downeaster passing tracks)
-- Wilmington (both platforms shifted to south side of bridge abutments creates full room for center passing track)
-- West Medford (room to spread out and drop center passing track)
-- Norwood Central (room on ex- tri-track space to spread out and drop center passing track).