Bowker Overpass replacement?

[themissinglink]

In 2015, an engineering student at Northeastern and Prof. Peter Furth conducted a detailed analysis of the proposal to remove the Bowker overpass. The report has been shared here before, but it's worth sharing again.

 

[F-Line to Dudley]

Caveating that I’m not a car person at all, and would love to see the Bowker removed in theory, in practice Longwood is one of the region’s most important employment centers, and due to the presence of hospitals one in which employees must be in person, and trucks and motor vehicles for infirm visitors are a necessary evil. I just searched Google Maps for the recommended route to Longwood from a variety of locations north, east, and west of the city. For nearly all of them, apart from a few locations in Cambridge and Allston, the recommended route is the Bowker. The alternatives, including the BU Bridge rotary and Mass Ave, aren’t exactly famous for being light on traffic. Any serious proposal to remove the Bowker I think has to grapple with how you get people from all these disparate locations to Longwood without just pushing traffic around to other locations that are also at capacity.

Sanely-timed signals. Longwood is a bitch to get to because the combination of BTD and DCR signals you have to traverse to get the very short distance between Storrow and the LMA have some of the worst goddamn timings known to man. The Northeastern study linked to in @themissinglink's post was all about synchronizing the surface signals between Boylston and Storrow in the north-south direction, Mass Ave. and Kenmore in the east-west direction to get rid of the bulk of the traffic constipation. An all-surface Charlesgate performed with fully adequate LOS if you gave the signals a whole-area treatment. MassDOT flat-out didn't model that alternative, opting not to touch the jurisdictional hornet's nest of whose signals are whose. It left the current signal anarchy in-place, which tanks the LOS for a surface option and puts the finger on their preordained "rebuild the viaduct" solution. It's the brute-forcingest way of doing it. Traffic's still going to be bad getting around because after the bounds of the physical project area you've still got loads of wretchedly-timed signals (especially the DCR ones).


EDIT: Here's the YouTube video explaining the NU study's methodology with live traffic modeling:

 

[wicked]

Not sure what benefit Cambria Street would offer, especially considering the Pru exit brings you out to Dalton and Huntington.

 

[BeansTheCat]

One other thing to note is that even if there is genuinely a drop in roadway capacity from removing Bowker, it does not need to be replaced by road capacity. The transportation system as a whole needs pick up the slack, whether it's the T, walking, cycling, or anything else. Increasing the Commuter Rail frequency at Landsdowne, improving that station's connection to Kenmore, and having a safe cycling route from the Esplanade all the way to Longwood could cause hundreds of trips to mode shift. And if I'm not mistaken, all three of those are currently planned to be addressed soon.

 

[RandomWalk]

Not sure what benefit Cambria Street would offer, especially considering the Pru exit brings you out to Dalton and Huntington.

I was proposing an eastbound on ramp.

 

[BOS2BON]

Sanely-timed signals. Longwood is a bitch to get to because the combination of BTD and DCR signals you have to traverse to get the very short distance between Storrow and the LMA have some of the worst goddamn timings known to man. The Northeastern study linked to in @themissinglink's post was all about synchronizing the surface signals between Boylston and Storrow in the north-south direction, Mass Ave. and Kenmore in the east-west direction to get rid of the bulk of the traffic constipation. An all-surface Charlesgate performed with fully adequate LOS if you gave the signals a whole-area treatment. MassDOT flat-out didn't model that alternative, opting not to touch the jurisdictional hornet's nest of whose signals are whose. It left the current signal anarchy in-place, which tanks the LOS for a surface option and puts the finger on their preordained "rebuild the viaduct" solution. It's the brute-forcingest way of doing it. Traffic's still going to be bad getting around because after the bounds of the physical project area you've still got loads of wretchedly-timed signals (especially the DCR ones).


EDIT: Here's the YouTube video explaining the NU study's methodology with live traffic modeling:

We should put this in a time capsule so maybe this gets done in another 50 years.

 

[wicked]

Sanely-timed signals. Longwood is a bitch to get to because the combination of BTD and DCR signals you have to traverse to get the very short distance between Storrow and the LMA have some of the worst goddamn timings known to man.

I heard a report recently (?) about DCR possibly ditching oversight of the “parkways.” That would be a big help here.

 

[TheRatmeister]

I understand the desire to eliminate the Bowker overpass. But it seems really problematic without also adding an Eastbound entrance/Westbound exit for the Pike someplace in Back Bay or Fenway. Otherwise you are reducing regional highway access for a significant, economically important, quadrant of the city.

I've always preferred shortening the overpass rather than entirely removing it. Connecting it to a Pike exit rather than Storrow eliminates many of the negative effects on the city but still retains highway access for Longwood which I agree is important.

 

[Charlie_mta]

I've always preferred shortening the overpass rather than entirely removing it. Connecting it to a Pike exit rather than Storrow eliminates many of the negative effects on the city but still retains highway access for Longwood which I agree is important.

Herse are a couple of possible ramp options for the Mass Pike:

This one by MassDOT a few years ago, for a westbound off-ramp to Berkley st and Columbus Ave:

And this one I laid out myself for an on-ramp from a truncated Bowker to eastbound Mass Pike:

 

[JeffDowntown]

Herse are a couple of possible ramp options for the Mass Pike:

This one by MassDOT a few years ago, for a westbound off-ramp to Berkley st and Columbus Ave:

View attachment 66313

And this one I laid out myself for an on-ramp from a truncated Bowker to eastbound Mass Pike:

View attachment 66314

The Bay Village ramp is too far east to help much with Longwood access.

 

[dhawkins]

Some activity at the Commonwealth east bound side, construction fence and more trees cut down. Looks like construction is underway. Sorry no pics.

 

[Charlie_mta]

The Bay Village ramp is too far east to help much with Longwood access.

No problem. Eliminate the westbound onramp from Mass Ave and replace it with an offramp. Proposed, and existing shown below:

 

[bbfen]

Or, do both: a flying junction at the Newbury Extension for a west-bound on-ramp and west-bound exit ramp to Comm Ave.

(Has the added benefit of pissing off the Harvard Club.)

 

[TallIsGood]

I very much doubt it. It's already painful to drive into Boston (and many other major cities), and yet people still visit in droves. Not to mention, Phil Eng has been making significant improvements to the MBTA that will encourage more people to leave their cars behind and use the T.

Who is going to avoid Boston because the Bowker overpass comes down? A handful of sheltered suburbanites who care more about driving than the city itself?

Yep. The ones who drive in to work, go to shows, sporting events, shopping and dinners.

 

[themissinglink]

Yep. The ones who drive in to work, go to shows, sporting events, shopping and dinners.

Boston will survive without a small handful of suburbanites who only visit once or twice a year for dinner or a ballgame. The city will keep on thriving.

 

[TheRatmeister]

Yep. The ones who drive in to work, go to shows, sporting events, shopping and dinners.

...during rush hour? Somehow I'm doubtful that applies to anyone besides workers. (And as discussed previously, some kind of access to Longwood would need to be maintained.)

Also, again apart from workers those are big inelastic sorts of demand. Sporting events and shows will draw people in from huge distances, and people go to Boston to shop or eat because there are unique stores or restaurants not available elsewhere. If travel time increases by say 10 minutes, that probably doesn't change for the calculus for most of those people on whether to go or not.

 

[HenryAlan]

The Bay Village ramp is too far east to help much with Longwood access.

No problem. Eliminate the westbound onramp from Mass Ave and replace it with an offramp. Proposed, and existing shown below:

I think you could do a westbound off ramp connecting to Newbury Street behind Kenmore Square, which would avoid eliminating the eastbound on ramp from Mass Ave.

 

[Koopzilla24]

MassDOT traffic counts for this area show the most used segment of roadway is the left-turning segment of Boylston St onto Charlesgate by nearly 10,000 vehicles over the second highest count, which is the exit of Bowker onto Boylston. Of note though is 13,000 cars are simply exiting onto Comm Ave compared to 28,000 that continue onto Storrow, plus an additional 8,000 that use Charlesgate E to get onto Storrow. Taking this into account, I think it'd be better to maintain only an overpass over the Pike to connect Boylston to Comm and Beacon without further clogging up Mass Ave, but using the Charlesgate E/W for Storrow access. The current daily traffic volumes of Bowker Overpass are just within the daily capacity of Charlesgate at 2 lanes but taking human behavior into account, I'd imagine having to go through the lighted intersections instead of the overpass would be enough to discourage at least a few thousand a day from using these surface roads if they don't necessarily have to.

 

[cubbe8]

10/1

 

[cubbe8]

10/15

Median has been removed on Boylston Street east of the overpass and the Boylston Street has been milled west of the overpass. Temporary signals on wooden poles have been installed at the intersection. Bridge abutments are being formed.