This is the "crazy" thread. So it doesn't have to be worth the cost, nor worth more than potential projects.
That said, I'm not sure this would be "worse" for the Red Line than it currently is.
I dunno. It can be 'crazy', but at very least there needs to be some sort of justification. An outright transit-loss situation for multiple communities that more or less fights max ridership potential to a draw...or only gets a nickel's return on investment in boardings for every dollar spent...doesn't point to a net-gain. But I weight transit loss as a cardinal sin given the state's history with that. Moreso for Braintree than the Greenbush Line...although whacking the Greenbush Line does reverse yet another Transit Commitment. We don't have to like how it turned out, but transit injustice against somebody encourages more transit injustice against everybody. (And no, forking the Braintree branch to a branch-off-a-branch to preserve Braintree doesn't work for traffic loads...it punishes everyone at the ends with diffuse commuter rail-like frequencies and torpedoes Braintree's boardings.)
Weymouth Landing is somewhat analogous to Braintree but in somewhat poorer location with somewhat poorer connectivity...so it takes more than a 1:1 swap to offset the loss of existing and future Braintree boardings (which are nice and all-day robust above and beyond a commute hours park-and-ride). The other two offer considerably poorer connectivity and are much more 9-5 M-F park-and-ride oriented. The boardings are going to crater on the off-peak, and their ceiling...even if you flush RL service much denser than today...is not going to top 50-60% of the Braintree, Quincy Adams, Wollaston grouping. That kind of drop-off probably means the T has to short-turn on the well off-peak at QA or WL because the farebox recovery will be so lousy. A fait accompli that service will be suspended past QA on the off-peak if, as you suggest, they have to maneuver time separation for crossing freights. Now you truly are no better off than where you started for stimulating ridership outside the park-and-riders and your max cap truly is in range of existing conditions + trying to stimulate the CR stops with something no-build.
Flunks the do-no-harm test egregiously. Flunks the ROI test on ridership...which at minimum needs to do
something substantially better than existing conditions + lift the growth ceiling substantially better to merit as a "crazy" instead of "OCD" pitch.
As for the freight; if it only moves once a day -- particularly at night -- then it doesn't need to be grade seperated.
Not quite. Fore River Transit runs mid-afternoon from the shipyard to Braintree. That's why Greenbush is double-tracked from the junction to Allen St. CSX runs from Middleboro after the last Middleboro train of the night to pick up those tankers up and haul back to Framingham. They are allowed by contract to change up time slots when necessary (since the weekend shutdowns they've been doing these moves early on Saturdays), CSX can switch the run out of Readville at-will, and after long weekends when CSX has gone an extra day without a pickup Fore River is allowed to store cars on the 2nd Greenbush track if Braintree yard is full or do extra runs if the shipyard storage tracks are full (which usually also necessitates CSX going for an earlier pickup). There's no RiverLINE time separation to be had here. The plant runs 24/7/365 and fills those tankers at a constant rate. If the trains aren't running because of service disruption they have to step up and clear the yards before they're full.
Plus, the Red Line work cars are out there 6 nights a week....track work, equipment swaps, and a general-purpose trash pickup train that runs end-to-end until it's full of trash bags. The branches arguably more active than the subway because they're outdoors and all the yards are clustered down there.
And the high ridership stops on the Greenbush Line are because of..... parking.
Right, but like I said at the top rapid transit isn't geared to stops that crater outside the 9-5 M-F commute hours. That's a waste of the mode. CR is where that's best. Of course it was a lousy decision to weight Greenbush so heavily to cars, but how does swapping modes change that calculus anywhere except Weymouth Landing's 1:1 swap for Braintree. The rapid transit park-and-rides DO have all-day ridership because of the density of where they're situated, the bus connections, and (at least in Braintree's case) ample TOD. If you don't have that anywhere east of Weymouth Landing or much potential to tart them up with TOD because of the strictly moderate-density surrounding residential...you're swapping one monument of waste for another. With transit loss. That ought to be the standard for a no-go.
It's the same reason I think Orange Line west of West Roxbury at 128 is a really bad idea. The 9-5 orientation of the highway stop would stick out like a sore thumb systemwide when the off-peak trains are empty, and there's bupkis for bus connections. It would induce off-peak short-turning, a big crater in daily boardings vs. the rest of the line, and get skewered just as badly as Greenbush--or worse--as a failure. There's simply no way to buttress the all-day ridership with nothing around for miles but quiet residential and parkland. Highway traffic alone doesn't float it. The other 128-area performers--Riverside, Quincy Adams + Braintree--have other things going for them than just a lot of state highway traffic whizzing by.
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