I-695, Soutwst X-Way, Mystic Valley Prkway, S. End Bypass

[Shepard]

It's slightly difficult for suburbanites driving into the city to navigate, so it must be fixed immediately.

I agree with the sentiment, but this interchange is very important regionally - not just for car commuters, but also for park-and-ride rail commuters (CR/Acela/Amtrak at the Route 128 stop), not to mention shipping. I think a fix is more than justified here.

Edit: For map enthusiasts, this interchange also contains one of the area's strangest Bridge to Nowhere, the Green Lodge Street overpass.

 

[Ron Newman]

If dropping to one lane is a problem, why not just widen the cloverleaf ramp to two lanes and be done with it?

 

[HenryAlan]

I think the problem is more the sharpness of the curve. You have to drop from 65 mph down to about 20. It's also hard to see at night. I think there are some intermediate options, such as widening, better lights, etc., but the fundamental issue is that it's a sharp right hook requiring too significant a decrease in speed. Even with two lanes, it would likely cause back-ups just from slowing vehicles.

 

[F-Line to Dudley]

I think the problem is more the sharpness of the curve. You have to drop from 65 mph down to about 20. It's also hard to see at night. I think there are some intermediate options, such as widening, better lights, etc., but the fundamental issue is that it's a sharp right hook requiring too significant a decrease in speed. Even with two lanes, it would likely cause back-ups just from slowing vehicles.

That's exactly what happens. It backs up past the 93N exit and then the whole highway is hosed back into Sharon. 95's the busiest trucking route in the nation. It's the trucks that slow to 20 on the curve making everyone slow to 20. The problematic inner loop of the cloverleaf to 128N is constrained by the less problematic outer loop from 93S. You'd have to massively widen the 93 off-ramp and weave it on the existing overpass with an S-curve to open the breathing room to widen the 128N onramp modestly. Medium northbound relief with tradeoff that southbound gets worse and has more weaving. By this point addressing those problems prices it same as fixing it right by starting over with a clean high-speed T-interchange, because those overpasses are also at end of structural life and need a full redecking if you keep them.

 

[Ron Newman]

I was thinking the opposite -- reduce the radius of the loop even further by widening the loop to two lanes. Leave the other ramps alone. Trucks can slow down to 20 mph in the new tighter inner lane while the rest of the traffic passes at 45 mph in the outer (existing) lane.

This would be a lot less expensive than entirely rebuilding the interchange.

 

[omaja]

And a whole lot less helpful. While I don't have exact numbers off hand, I'd guess 93 and 95 handle somewhere near 200K vehicles per day in the area of that interchange. The current set up only functions properly with approximately a fourth of the volumes it is handling.

 

[whighlander]

That's exactly what happens. It backs up past the 93N exit and then the whole highway is hosed back into Sharon. 95's the busiest trucking route in the nation. It's the trucks that slow to 20 on the curve making everyone slow to 20. The problematic inner loop of the cloverleaf to 128N is constrained by the less problematic outer loop from 93S. You'd have to massively widen the 93 off-ramp and weave it on the existing overpass with an S-curve to open the breathing room to widen the 128N onramp modestly. Medium northbound relief with tradeoff that southbound gets worse and has more weaving. By this point addressing those problems prices it same as fixing it right by starting over with a clean high-speed T-interchange, because those overpasses are also at end of structural life and need a full redecking if you keep them.

F-Line -- as usual a very thorough posting on transportation issues
Omaja -- yes its 200k range and as pointed out -- everyone headed north is either heading NW on I-95 N or NE (although some might then head S on 3) on I-93 (never can figure out if its north or south)

There are some who really are headed to RT-128 T and Amtrak station and the new development -- the will be getting a private ramp as part of the rebuild of the interchange

The other two with much of the same problems are:
I-93 / I-95 in Woburn and
I-93 / Rt-3 in Braintree

Both are planned to be fixed the next 20 years along with the I-95 N T interchange -- rebuilding from scratch using modern traffic interchange designs

 

[Ron Newman]

But I-93/MA 3 in Braintree is not a cloverleaf, so why does it need any rebuilding?

 

[vanshnookenraggen]

It is a cloverleaf, albeit a half built one. Actually it is a trumpet hacked out of a half built cloverleaf.

http://g.co/maps/g7w9g

You can clearly see the old ramps never completed.

 

[mass88]

But I-93/MA 3 in Braintree is not a cloverleaf, so why does it need any rebuilding?

The entire interchange is terrible. Going north on 95 and getting onto 93 needs to be redone. There will be a backup, even though there isn't any traffic. I would have a dedicated lane added onto that stretch of 93 where only those merging on would have access initially then open it up and it be an exit only lane for the first exit.

The split by the Plaza is a lot smoother than the one in Canton.

 

[F-Line to Dudley]

But I-93/MA 3 in Braintree is not a cloverleaf, so why does it need any rebuilding?

That one's not going to get a full rebuilding. The rock formations they blasted through to make it won't allow it so the two highways are locked in to the current configuration. It's the close-spaced exits all feeding right into the Split that are getting fixes to eliminate a lot of weaving. They're going to push back the Route 37 exit with longer deceleration/acceleration lanes and make a frontage road that ties it in to the whole Washington St. ramp complex on the entrance side. Spaces out all the mainline merges and gives better public transit access for 37 and the Mall without needing to interact with the Split. Also includes short acceleration lane additions at the 3/18 exit and 93/Furnace Brook Parkway exit to ease the post-split weaving and enable better access to the HOV lane, and some changes to the Burgin Parkway interchange.

Goal is simply to get all those auxiliary ramps pushed further away from the main interchange so the 93/3 mainline traffic has more breathing room to sort and weave itself before all these side ramps come zooming in. Interchange will always have natural constraints and capacity problems, but this fixes the worst parts of the design.


Separate project also considers modifying the 24/93 T-interchange to eliminate the left exit/merge on 93S with a flyover and too-close spacing with the 28 and Ponkapoag interchanges. That one's not as big a deal, though, because they're thinking of it as a 3-phase--short, medium, and long-term--that first does some cosmetic improvements to collection/distribution on the 28/Ponkapoag exits for weave elimination. Then adding travel lanes a ways back on 24 and 93 to eliminate lane drops. Then an optional finish at some point modifying the ramps to eliminate the left lane merges, but skipping that one if it's excessive.

Exit spacing truly is a little nutty between 1/95/24/28, then at ground zero of the Split. All that collection/distribution improvement is half the battle.

 

[Ron Newman]

It is a cloverleaf, albeit a half built one. Actually it is a trumpet hacked out of a half built cloverleaf.

http://g.co/maps/g7w9g

You can clearly see the old ramps never completed.

This is not the I-93/MA 3 interchange in Braintree.

 

[Ron Newman]

The entire interchange is terrible. Going north on 95 and getting onto 93 needs to be redone.

But what does that have to do with the I-93/MA 3 interchange in Braintree?

 

[BostonUrbEx]

If the 95/128 interchange can't handle the volume, add ramps and a bigger garage at the Amtrak/MBTA station. Run DMUs from SS to 128 via Fairmount.

 

[omaja]

Traffic is multi-directional. Adding commuter rail service doesn't do anything for the majority of traffic whose destination is elsewhere in the region.

 

[Equilibria]

If the 95/128 interchange can't handle the volume, add ramps and a bigger garage at the Amtrak/MBTA station. Run DMUs from SS to 128 via Fairmount.

That assumes that most of that volume is going to Downtown Boston. That is a huge, and IMO incorrect assumption...

 

[whighlander]

That assumes that most of that volume is going to Downtown Boston. That is a huge, and IMO incorrect assumption...

Equilib -- just watch the morning TV traffic graphics and video cameras--- most traffic on the major radials (I-93, Rt-2, I-90, Rt-1) heading in-bound just inside of Rt-128 is destined for Boston Financial District, Back Bay, Longwood area, or Kendall Sq. in Cambridge now, and perhaps also the SPID in a decade or so

However, if you look at the flow inbound from I-495 a along radials such as i-93 and Rt-2 a substantial fraction exits the radial at Rt-128 and goes circumferential to some suburban park -- not much flows as some might expect to another radial

Even futher out -- a lot of the ex-urbs flowing in on radials to I-495 never goes beyond the I-495 region -- but moves circumferentially to generally large clusters on / near I-495 such as Intel, IBM,Cisco

This comple pattern makes it very difficult for the T to do much more than what it currently does -- move people in/out from the Hub of the HUB

I used to thinkthat it would be viable to take the old 1968 radial T extension map and link the ends together using a line runing along RT-128 -- I no longer believe that this would be viable on Rt-128 as there are two many small to medium clumps of employment which are not close enough to interconnect except by car

On I-495 the clumps are bigger -- but the distances are larger so that the conclusion is the same

 

[F-Line to Dudley]

Equilib -- just watch the morning TV traffic graphics and video cameras--- most traffic on the major radials (I-93, Rt-2, I-90, Rt-1) heading in-bound just inside of Rt-128 is destined for Boston Financial District, Back Bay, Longwood area, or Kendall Sq. in Cambridge now, and perhaps also the SPID in a decade or so

However, if you look at the flow inbound from I-495 a along radials such as i-93 and Rt-2 a substantial fraction exits the radial at Rt-128 and goes circumferential to some suburban park -- not much flows as some might expect to another radial

Even futher out -- a lot of the ex-urbs flowing in on radials to I-495 never goes beyond the I-495 region -- but moves circumferentially to generally large clusters on / near I-495 such as Intel, IBM,Cisco

This comple pattern makes it very difficult for the T to do much more than what it currently does -- move people in/out from the Hub of the HUB

I used to thinkthat it would be viable to take the old 1968 radial T extension map and link the ends together using a line runing along RT-128 -- I no longer believe that this would be viable on Rt-128 as there are two many small to medium clumps of employment which are not close enough to interconnect except by car

On I-495 the clumps are bigger -- but the distances are larger so that the conclusion is the same

Getting more people taking commuter rail on the 3 corridor would help a lot. Unfortunately the Old Colony lines are choked by that 1-track segment in Dorchester next to 93 that would take a billion to fix. I think they can help it a bit by getting second platforms at Quincy Center when it's renovated soon and at JFK so train meets can be eliminated at platform sidings. That'll allow a handful more trains to be added to the schedule. Kingston and Middleboro are outperforming their ridership projections by a lot and would swallow up any more trains they got. It's the spoiled brats on the Greenbush line who are the ones needing to get with the sustainability program here.

The only place I think South Coast Fail is going to make a real positive difference is north of Taunton with 24, the other roadway that clobbers the Split. Easton, Raynham, and downtown Taunton stations help that a lot. So would a terminating park-and-ride station at 24/140/Silver City Galleria if they tacked that on as a short Phase 1⅓ after downtown Taunton. That would be like a second Middleboro in terms of park-and-ride utilization, and would be the ideal place for the New Bedford and Fall River buses that should be running instead of this asinine money pit. Problem is that should really be considered its own independent CR project on its own merits with the Fail portion south of there killed with a stake through the heart like the blood-sucking vampire it is. It's much more useful terminating at the east-west Middleboro Branch, because then your next step can be sending the cavalry to M'boro to double-up that park-and-ride at 495 and go to Buzzards Bay to siphon off the Cape end of the 3 traffic with better headways than the Old Colony chokepoint could deliver. The insanity of FR/NB is that that should really be step three in a multi-decade buildout, not the one we light all our money on fire to do first.

I'm pretty confident Fairmount Line will be running to 128 in 5 years. We may see a few mil's grant as early as next year to tri-track Readville-Canton for congestion relief because that's a trivial one requiring no station work (Westwood/128 outbound's already built as an island for the 3rd track) and they can do it track-only and add the Amtrak wire later. When the other Fairmount upgrades are done they want to tack on an island platform at Readville center of the ROW so headways aren't constrained by the 1-track platform and they can run more Franklin schedules through the existing platform without interference. New one would be angled on the seldom-used 2 tracks connecting to the NEC, not the Franklin flyover. That's the dead giveaway that Fairmount to 128's a bona fide short-term goal. They might get some funding to do that extra platform when they raise the Readville platforms and fix the 1-track Franklin bottleneck per Amtrak's requirements for level-boarding upgrades in commuter rail territory. The 3-track setup at 128 will handle turns there for a little while until SCR is built. But then there's space under the 128 bridge and on the other side of the station for a whole new platform and 2 more tracks splitting off right before the underpass. That platform would ultimately be Fairmount's exclusive domain for turns.

I think we are getting that within 5 years of the current Fairmount project wrapping. 128 is very low-hanging fruit co-mingled with a whole bunch of minor area Amtrak improvements already in the pipeline. They can claim for an expedited funding appropriation that it's serving the Westwood Station real estate development even though it's really the park-and-riders from 95/1/128 who are going to be packing it full every day.

 

[whighlander]

Getting more people taking commuter rail on the 3 corridor would help a lot. Unfortunately the Old Colony lines are choked by that 1-track segment in Dorchester next to 93 that would take a billion to fix. I think they can help it a bit by getting second platforms at Quincy Center when it's renovated soon and at JFK so train meets can be eliminated at platform sidings. That'll allow a handful more trains to be added to the schedule. Kingston and Middleboro are outperforming their ridership projections by a lot and would swallow up any more trains they got. It's the spoiled brats on the Greenbush line who are the ones needing to get with the sustainability program here.

The only place I think South Coast Fail is going to make a real positive difference is north of Taunton with 24, the other roadway that clobbers the Split. Easton, Raynham, and downtown Taunton stations help that a lot. So would a terminating park-and-ride station at 24/140/Silver City Galleria if they tacked that on as a short Phase 1⅓ after downtown Taunton. That would be like a second Middleboro in terms of park-and-ride utilization, and would be the ideal place for the New Bedford and Fall River buses that should be running instead of this asinine money pit. Problem is that should really be considered its own independent CR project on its own merits with the Fail portion south of there killed with a stake through the heart like the blood-sucking vampire it is. It's much more useful terminating at the east-west Middleboro Branch, because then your next step can be sending the cavalry to M'boro to double-up that park-and-ride at 495 and go to Buzzards Bay to siphon off the Cape end of the 3 traffic with better headways than the Old Colony chokepoint could deliver. The insanity of FR/NB is that that should really be step three in a multi-decade buildout, not the one we light all our money on fire to do first.

I'm pretty confident Fairmount Line will be running to 128 in 5 years. We may see a few mil's grant as early as next year to tri-track Readville-Canton for congestion relief because that's a trivial one requiring no station work (Westwood/128 outbound's already built as an island for the 3rd track) and they can do it track-only and add the Amtrak wire later. When the other Fairmount upgrades are done they want to tack on an island platform at Readville center of the ROW so headways aren't constrained by the 1-track platform and they can run more Franklin schedules through the existing platform without interference. New one would be angled on the seldom-used 2 tracks connecting to the NEC, not the Franklin flyover. That's the dead giveaway that Fairmount to 128's a bona fide short-term goal. They might get some funding to do that extra platform when they raise the Readville platforms and fix the 1-track Franklin bottleneck per Amtrak's requirements for level-boarding upgrades in commuter rail territory. The 3-track setup at 128 will handle turns there for a little while until SCR is built. But then there's space under the 128 bridge and on the other side of the station for a whole new platform and 2 more tracks splitting off right before the underpass. That platform would ultimately be Fairmount's exclusive domain for turns.

I think we are getting that within 5 years of the current Fairmount project wrapping. 128 is very low-hanging fruit co-mingled with a whole bunch of minor area Amtrak improvements already in the pipeline. They can claim for an expedited funding appropriation that it's serving the Westwood Station real estate development even though it's really the park-and-riders from 95/1/128 who are going to be packing it full every day.

F-Line thoughful analysis

However i think you missed a couple of issuses:

1) Plymouth (very large area open or growth) is developing into a regiional sub-core similar to Waltham and Framingham -- this could happen to South Weymouth too if the full build-out of old Naval Air Station occurs

The net is that Plymouth at least will eventually be a destinaion as well as a source of commuters and possibly a local transfer hub -- people coming north from the Cape and the SE Cranberry Bog area

2) Foxboro has huge immedaite potential as a commuter park and ride using the stadium lot -- what is needed is gerbil tube and moving walkway from a new bettter station location to the parking lot and the stadium as well as other developable land

in the long term -- Foxboro also could generate detination traffic as well as being a source for commuters -- the time to invest to develop a train culture at / through Foxboro is now -- because of TOD potential -- Patriots should be willing to invest

3) Electrification along the coast toward the Cape and SE inland S down to Foxboro is something to be considered to enable high frequency of departure single car "Electric Buddlliners"

 

[F-Line to Dudley]

F-Line thoughful analysis

However i think you missed a couple of issuses:

1) Plymouth (very large area open or growth) is developing into a regiional sub-core similar to Waltham and Framingham -- this could happen to South Weymouth too if the full build-out of old Naval Air Station occurs

The net is that Plymouth at least will eventually be a destinaion as well as a source of commuters and possibly a local transfer hub -- people coming north from the Cape and the SE Cranberry Bog area

2) Foxboro has huge immedaite potential as a commuter park and ride using the stadium lot -- what is needed is gerbil tube and moving walkway from a new bettter station location to the parking lot and the stadium as well as other developable land

in the long term -- Foxboro also could generate detination traffic as well as being a source for commuters -- the time to invest to develop a train culture at / through Foxboro is now -- because of TOD potential -- Patriots should be willing to invest

3) Electrification along the coast toward the Cape and SE inland S down to Foxboro is something to be considered to enable high frequency of departure single car "Electric Buddlliners"

F'boro's commuter rail study is a nice read. That is REAL low-hanging fruit. I think it's got excellent chance of happening fast and sudden. The only build required is double-tracking the Franklin from Norwood Central to Windsor Gardens, rehab and signalization of 5 miles of track on the Framingham Secondary, installation of a crossover at Franklin layover to eliminate all schedule conflicts with Franklin trains, and a layover yard at Foxboro. $63M total via last year's projections. About half of that for the layover yard...the track rehab is only like $20M. Would run via Fairmount, 79 MPH to Walpole, 60 MPH to Foxboro. Foxboro-Mansfield would be signalized in the package so Providence Line trains could be diverted via Walpole at any time in a service emergency, but the track there would only get bumped to the 40 MPH needed for freight.

Only further items left to work out are how exactly do they handle commuter parking at same time as Gillette weekday games, and what are commuters' comfort level at not getting a one-seat to Back Bay because of the Fairmount routing. Otherwise this is looking so good and cheap the funding could materialize on short notice without needing to go on any long-range plan first.

Foxboro's proposing a limited test service that could begin next year if $1M were appropriated just for CSX to fix up the track from the 25 MPH deferred maintenance it's currently at to the 40 MPH it was originally rated. Needs to be done regardless only for freight so CSX isn't weight-restricted to Attleboro, so would merely push up the schedule on something that's planned regardless. They'd run 2 or so slow trains per rush hour with not a single penny's other improvements, see how people like it, and then fast-track the full build if it looks bullish. Excellent strategy doing some road-tests and priming the route before they do it. Why can't they try this with New Bedford via Middleboro and Fall River via Attleboro by just running 2 per day via the Middleboro Secondary to bare platforms at the terminals and seeing if anyone gives a crap? That freight track's being upgraded right this second and is supposed to get the same immediate-term 40 MPH maint backlog fix for the freights.