Unbuilt roads around metro Boston

[Charlie_mta]

You'll notice in the link I provided that a super-2 expressway is by definition "a high-speed surface (limited-access) road with at-grade intersections." In fact, MA-88 is specifically listed as an example of a "two-lane expressway" on the wiki page for "two-lane expressway."

Our disagreement is just simply a difference in how we're using the terminology. I'm using the actual definition of the terminology as evidenced by the links provided. You are clearly using a different definition. That's fine. It really isn't important.

Part of the difference in definition of an expressway has to do with regions of the country. In most of the US (except for the Northeast and Midwest), a "Freeway" is a fully grade separated, access-controlled highway, but an "Expressway" is something less than that, with some at-grade crossings. You see a lot of those types of "Expressways" in the San Francisco Bay area. However, in the Northeast and Midwest, the term "Freeway" isn't used, and "Expressway" means the same thing here as "Freeway" does in most of the US.

 

[bigeman312]

Part of the difference in definition of an expressway has to do with regions of the country. In most of the US (except for the Northeast and Midwest), a "Freeway" is a fully grade separated, access-controlled highway, but an "Expressway" is something less than that, with some at-grade crossings. You see a lot of those types of "Expressways" in the San Francisco Bay area. However, in the Northeast and Midwest, the term "Freeway" isn't used, and "Expressway" means the same thing here as "Freeway" does in most of the US.

That hasn't been my experience in how these words are used. My experience has been that in the Northeast, there is very little consistency in how the layman uses these terms. In fact, outside of transportation geeks, I generally only hear the word "highway" used, and not the words "expressway" or "freeway." This may be a generational difference in verbiage, it may even be a niche socio-economic or cultural difference. When in doubt, I'll stick with the textbook definition, for which MA-88 qualifies.

 

[JeffDowntown]

That hasn't been my experience in how these words are used. My experience has been that in the Northeast, there is very little consistency in how the layman uses these terms. In fact, outside of transportation geeks, I generally only hear the word "highway" used, and not the words "expressway" or "freeway." This may be a generational difference in verbiage, it may even be a niche socio-economic or cultural difference. When in doubt, I'll stick with the textbook definition, for which MA-88 qualifies.

I always thought that freeway was a Western differentiator for open, free expressways, versus turnpikes, which are tolled (historically in the Northeast, close MidWest).

 

[F-Line to Dudley]

It also doesn't explain why Steve Anderson thought it should get all grade-separated intersections...

The roadway has a really bad accident history from inattentive drivers blowing through reds, especially in fog. That's why upgrade was semi-promised by the state in the 90's and some local pols were pissed that they never followed through.



I dunno about the whole thing, but the Briggs Rd. intersection in Westport should probably get separated since MA 177 immediately south of there is a full separated diamond interchange that's the last dumping point for any truly heavy traffic loads on the roadway. NB drivers get lulled into false sense of security thinking it's all limited-access from there and get surprised when there's one more stoplight a mile north...leading to some of the nasty accident rates.

 

[RandomWalk]

Couldn’t they take the road and slow it down with a similar footprint and slower curves or chicanes?

 

[F-Line to Dudley]

Couldn’t they take the road and slow it down with a similar footprint and slower curves or chicanes?

It has three arrow-straight segments of >2 miles each, each of them with very long permissive passing segments of striped yellow line. The entire roadpack was purpose-designed to be a drag strip. I don't see how you could throw enough artificial traffic-calming devices around it without that effort itself being a self-defeating cost. It's not like this would be anything resembling an easy "boulevarding" retrofit.

Volumes are pretty damn low south of 177. Briggs is the one intersection that has the high fatality rates due to it being sandwiched between the 'true' limited-access segments. It'll honestly be cheaper to just zap that one entirely with a bridge and take away most of the liability risk while leaving the other intersections south of 177 stet.

 

[RandomWalk]

Solve it Indiana-style with a roundabout.

 

[F-Line to Dudley]

Solve it Indiana-style with a roundabout.

Go take one glance at the absolutely horrifying Otis & Bourne Rotaries crash stats...or the pair on 128 in Gloucester...and head straight back to the drawing board, because here of all states rotaries with >50 MPH feeders do less than nothing to positively condition rider behavior. It would quite likely make things even less safe.

Again...the volumes fall off the table south of 177, and there's no design inconsistency with the 4 southerly intersections like there is with Briggs shivved like an unwelcome surprise between two high-speed limited-access interchanges. This doesn't take grandiose thinking or purely performative measures that pretend the road is something other than what it quite obviously is.

 

[sm89]

Go take one glance at the absolutely horrifying Otis & Bourne Rotaries crash stats...or the pair on 128 in Gloucester...and head straight back to the drawing board, because here of all states rotaries with >50 MPH feeders do less than nothing to positively condition rider behavior. It would quite likely make things even less safe.

Those aren't roundabouts though. Roundabouts are much safer than the rotaries we have here. They are typically the safest type of intersection control.

 

[F-Line to Dudley]

Those aren't roundabouts though. Roundabouts are much safer than the rotaries we have here. They are typically the safest type of intersection control.

Roundabouts don't have feeders so extremely high-speed, though. It strains the design credulity of quaint little neighborhood roundabouts to feed a signed-55 MPH mainline bookended with miles-long permissive passing zones...where most vehicles are doing 70+ into them. They become high-speed rotaries all the same because there aren't enough traffic-calming tricks you can plausibly and within-cost enact on the approaches to slow them down safely into standard arterial roundabouts.


The solution can't be based on a pretense that MA 88 is somehow designed in a completely different way than it is very clearly designed. Whether it's a by-the-book expressway or not by some inherently squishy dictionary definition, it is 100% ground-up designed for expressway not arterial speeds. And that's not something easily changed about its design without incurring punitive cost. A low-speed roundabout is not going to fare better on safety than the signalized intersections if the approaches are still full-on expressway speed. It's going to AutoCAD-out into high-speed rotary territory very quickly under those parameters. And, well...Sweet Home Massholia doesn't have a particularly sterling rep for obedient behavior around high-speed rotaries.

 

[jass]

California is using roundabouts in rural areas where signed speeds are 55mph, and the roundabout is 15mph. It can be done.

Roundabout

Google Maps

Find local businesses, view maps and get driving directions in Google Maps.

www.google.com

Speed limit sign

Google Maps

Find local businesses, view maps and get driving directions in Google Maps.

goo.gl

Roundabout warning sign

Google Maps

Find local businesses, view maps and get driving directions in Google Maps.

goo.gl

 

[The EGE]

Putting utterly performative crosswalks at an intersection with absolutely no pedestrian activity, thus spending money for absolutely no benefit while claiming they're multimodal, is the most painfully Caltrans thing.

 

[jass]

Putting utterly performative crosswalks at an intersection with absolutely no pedestrian activity, thus spending money for absolutely no benefit while claiming they're multimodal, is the most painfully Caltrans thing.

Yeah thats a little odd. The plants too. Is someone really going to maintain those?

 

[F-Line to Dudley]

Yeah thats a little odd. The plants too. Is someone really going to maintain those?

Make them cheap dollar-store plastic faux greenery then rebrand them as "snowplow targets", and I bet we'd get a real proliferation of landscaped roundabouts here in these parts.

Otherwise, simply expecting the curbing to survive one winter season without getting giant chunks all torn out of it by plowblades is a wish too far.

 

[RandomWalk]

I am amused at how far my sarcastic suggestion has gone. Apologies for not tagging it as such...

I know full well how badly Massachusetts drivers would handle roundabouts.

 

[George_Apley]

I mean, MA drivers handle circular intersections better than any other region in the US. It's not a bad idea.

 

[North Shore]

I am amused at how far my sarcastic suggestion has gone. Apologies for not tagging it as such...

I know full well how badly Massachusetts drivers would handle roundabouts.

Better start getting familiar with them, as MassDOT has become a major proponent of them. More often then not, they require an alternatives analysis that includes a roundabout design option when constructing an intersection that meets a traffic signal warrant.

In fact, I'm currently designing a linked pair of roundabouts for a project in the middle of the state.

 

[Vagabond]

I know full well how badly Massachusetts drivers would handle roundabouts.

MA drivers have been handed pretty shit designs: we've been trained to have double-lane entry points with no clear lane merging, to hit the gas going into the turn to match prevailing speeds, and to switch lanes to find your exit.

The MA style Rotaries, with entering speeds >40 MPH are the dangerous ones. Rotaries that have added lights all over them like PowderHouse in Somerville destroy the traffic flow. Double/triple lane rotaries like Sullivan Sq are actively trying to murder bicyclists.

Designs for lower entry speeds, angled entry/exit points, smaller inscribed diameters, and deeper offset crosswalks with multiple islands work very well, maintain slow+steady flow, and have few accidents. Protected bike lanes ((re: concrete bollard to block truck trailer offtrack) should be on all 2-3 lane rotaries.

 

[Codman89]

Better start getting familiar with them, as MassDOT has become a major proponent of them. More often then not, they require an alternatives analysis that includes a roundabout design option when constructing an intersection that meets a traffic signal warrant.

In fact, I'm currently designing a linked pair of roundabouts for a project in the middle of the state.

Indeed. The state has been pretty keen on roundabouts and recently developed a white paper and design guide: https://www.mass.gov/lists/guidelines-for-the-planning-and-design-of-roundabouts

There's a lot of nuance with how they're designed, but in short if you think it's too much to ask people to slow down for a rotary then whoa boy. Let me tell you about what happens when people don't slow down/stop for a red light. Safety at intersections along high-speed roadways will always be difficult, but it's far preferable to have a few more drivers overrun curbs than to set up a situation where you'd expect high-speed T-bone crashes.

Not saying a roundabout is always the right solution, but a higher number of crashes isn't always a bad thing if crash severity is greatly reduced. Also, roundabout =/= rotary.

 

[Highwayguy]

Protected bike lanes should be on all 2-3 lane rotaries.

DOT policy is explicit that bike lanes not be provided on street through any roundabout. Off street accommodation must be provided which sounds good in theory but in practice usually consists of an otherwise unmarked 10’ concrete sidewalk.

In general though, there is no general prohibition on higher speed roads feeding a small diameter Roundabout. One on 28 in Milton with a 45 MPH arrow straight approach is under design now.

As far as one on 88 is concerned, plenty of room for traffic calming chicanes so vehicles dont barrel through the center island. The only factor that could preclude a roundabout would be if volumes are high enough to require 2 through lanes for the 88 approaches. These types of roundabouts can kill the LOS of the minor street approaches so the town may object. I’m personally not a huge fan of these types of roundabouts because generally the crossing angle of the minor street approach is high so they are not as safe as single lane roundabouts, but still much safer than a high speed signal. Might have a few more fender benders, but there wont be any insta-fatality 90 degree crashes at 50 MPH.