Deck The Pike Herald St. Extension

Ooh! So the tunnel from Tufts to South Station is not contingent on the N-S Link after all? Looks like the Transitway goes much further under Dewey Square than I had thought.
 
Ooh! So the tunnel from Tufts to South Station is not contingent on the N-S Link after all? Looks like the Transitway goes much further under Dewey Square than I had thought.

Yeah. It was the only way they could finagle the bus loop.

South End routing from Eliot Norton Park is 3500 ft. of new tunneling vs. 1800 ft. on Essex. But SL Phase III also had the crazy under-Common loop, Boylston Under station, and a crazy portal in an all-new and duplicate tunnel down Charles St. so it was longer tunneling than this. And even if you were do straight-shot it down Essex your only options are 1) create a Copley Jct.-on-Steroids into Boylston with an at-grade wye that has equally sharp, slow, and capacity-maiming left- and right-turns into the station and nukes the whole south end of the station, or 2) do the Silver Line under-Common crazy loops to in any way be able to interface with the station (blowing up access to the old tunnel in the process). Sure...might save you $1B from the BRT plan, but still cost $3B and be an absolute dog on speeds and general awkwardness.

So...yeah, embrace the South End runaround in all its surface and/or future tunnel permutations because you ain't ever going through Chinatown as the crow flies.


Addendum to the BBY tunneling leg: the Huntington tunnel joins Huntington Ave. off Copley Jct. at the Stuart/Exeter/Huntington intersection (squint real hard at that map), 1 block closer than I thought. That's good because the Pike crosses right under this intersection (just see on street view where the air rights decking is). So you can stay safely on the north side of the Pike tunnel wall off Stuart, rejoin the Huntington tunnel before the pre-existing Green Line passes under the Pike, and avoid any Mall impacts. Still going to be a couple invasive blocks west of Clarendon for doing the dance around Trinity Pl. and staying on the north side of the Pike retaining wall, but Exeter/Huntington construction vs. Ring/Huntington construction makes all the difference in the world here in terms of building impacts.
 
Would doing the deck, development and surface routing make the tunneling harder? Assuming that development is build on the land that used to be Marginal Street and Herald Street would underpinning those structures drive up the cost of a future subway?
 
Would doing the deck, development and surface routing make the tunneling harder? Assuming that development is build on the land that used to be Marginal Street and Herald Street would underpinning those structures drive up the cost of a future subway?

Not if the street grid remains unchanged. I can't fathom any air rights development impacting the flow of Marginal or Herald. They're pretty perfectly set up as a one-way pair serving all air rights development between Arlington St. and Harrison. Lane-drop Herald so the left lane matches the on-street parking setup of Marginal and it's just about perfect for interfacing the fronts of buildings.

Also, the Pike retaining wall wasn't altered very much when the Pru Mall 1980's air rights were plunked on top. It was pre-designed for this from the start. So the air rights construction does not require blowing up the streets the whole length of the wall, or tearing down the wall itself. The wall top would be altered to fit the crossbeams, uneven sections of wall would be topped off to even height (see the Tremont-Shawmut block where the Marginal side is short w/ grassy knoll on top while the NEC side goes full high), and any places requiring load-bearing support for tall buildings would get columns buried in the wall. Otherwise there is adequate load-bearing support for the deck given that the Pike center divider and Pike/NEC divider also get sets of load-bearing columns for the decking. Go take a Street View tour of the existing tunnel: http://goo.gl/maps/98fco. Ain't nuthin' but a prefab MassHighway overpass with standard overhead girders and those Pike-signature tubular support columns showing up as conspicuous humps in the left lane tile wall. Places like the Clarendon St. onramp merge where there's a building overhead the tubular columns give way to an ultra-long concrete slab column in the left lane wall. Those appear irregularly throughout the tunnel underneath buildings. Presumably the same structures would be buried invisibly in the right lane retaining walls, but as you can see from the left lane they're no thicker than the tubular columns...just longer and presumably deeper.


So no...nothing would alter what's underneath Marginal and Herald. During deck construction the streets would probably remain open throughout with left-lane closures and parking bans. There'd be no additional obstructions underground for building a transit tunnel on the other side of the retaining wall. If they needed to punch a small hole in the wall from inside the Pike air rights to get their dig equipment underneath and/or jack up the above street so it can remain open while constructing a Green Line tunnel segment, that would be possible even post- air rights.
 
Not if the street grid remains unchanged. I can't fathom any air rights development impacting the flow of Marginal or Herald. They're pretty perfectly set up as a one-way pair serving all air rights development between Arlington St. and Harrison. Lane-drop Herald so the left lane matches the on-street parking setup of Marginal and it's just about perfect for interfacing the fronts of buildings.

I see. I was basing my post on some of the ideas folks have had to use the new Pike Deck Blvd to replace Marginal and Herald and take over those streets for development.
 
I see. I was basing my post on some of the ideas folks have had to use the new Pike Deck Blvd to replace Marginal and Herald and take over those streets for development.

Yeah, in my proposal the tunnel would either be put in as part of the build out of the deck, or anyone developing the land formerly occupied by Marginal road would have to build a small piece of the tunnel as part of their building.
 
I've posted this idea before, heavily based on Davem's observation that a surface boulevard down the middle of the Pike trench could allow developments on either side which could be largely built on terra firma. Given the news about the Back Bay Station and Garage redevelopment, I've updated this accordingly to run the new boulevard through the existing garage and into the Stuart/Dartmouth intersection, leaving room for two new towers on the garage site.

I'm calling the boulevard Motte Parade, after a historical street that ran through the area. In terms of the developments facing onto Motte Parade, I've made sure that not a single existing property needs to be taken or redeveloped. And, none of the buildings that now have new developments alongside them actually face or interact at all with the now-developed side.

The new updated plans:

Motte Parade begins at the intersection of Stuart and Dartmouth, leaving a triangular plot on the former garage site for a 900-footer. Another tower gets situated on the other side of the block facing Clarendon. This view is from the upper floors of the Prudential. (Proposed Simon tower and Trinity Place towers not shown here).
muy0gw1.jpg


Motte Parade is a pedestrian-oriented boulevard. There is only one lane of traffic in each direction, along with a parking lane and cycle track. The road is 130' from building face to building face. A low-speed roundabout and new public plaza takes the place of what's now desolate bridges where Arlington and Tremont cross the Pike. I call this Chandler Circle.
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Chandler Circle looking west towards the new Back Bay towers.
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Elevation view of the new developments to be built along Motte Parade. No takings of existing property necessary, and no existing buildings are cut-off from their current intended uses.
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That'd make a great Olympic Village. Which may or may not be a good thing.
 
That'd make a great Olympic Village. Which may or may not be a good thing.

I really don't agree. Security would be hell.

I also wonder with something like this... it needs to be ventilated, right? Where would the vent buildings go?
 
I really don't agree. Security would be hell.

I also wonder with something like this... it needs to be ventilated, right? Where would the vent buildings go?

Sprinkle a few in along the way that blend in with the surrounding buildings a-la this guy in brooklyn.

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There are a few things I don't understand about this proposal. What is the economic rationale for this proposal? What is really to be gained from it. At best I can see a few small buildings (3-5 stories are too small), 100% covering of the Mass Pike which is frankly nice to have rather than critical*, and dropping an intersection from the North-South streets.

There are however many questions and potential problems that arise from this proposal. The foremost being cost - this is an extremely expensive and focused capital cost which I understand you propose to be state funded.

My other comments are below:

1. You say you won't take away any existing uses. What about the north side along Cortes St? Are you leaving Cortes St? If so, the width is not huge, but maybe an 8-10 story building would work here.

2. And this northern piece of 'terra firma' gets much more narrow as you continue east. Marginal is maybe 44' typically, maybe 10' more between Tremont and Shawmut. That would not make for much of a building.

And this new build would have no alleyway, no rear access, no service entrance. It might have underground parking, but it would be very awkward and costly.

3. On the southern side, there is a lot less terra firma. Between Columbus and Tremont there is none. To Shawmut there is a little wedge, but majority is still over tracks. So what benefit is to be gained here?

4. I'm not sure I understand the disposition of the new 'Back Bay Garage' towers. That's a pretty small strip you are talking about, maybe it works as a residential similar in size to the Copley Tower. But in addition you are eliminating the 2,000 parking space garage at 100 Clarendon. Presumably this is a 'taking'?

5. You are dropping 2 lanes (Marginal) + 3 lanes (Herald) = 5 lanes to 2 lanes of traffic. I normally feel there is plenty of car infrastructure in this city and traffic here is typically light, but for many others this will be quite a harsh pill.

6. Ventilation (already mentioned) might take at least one building on either side on each block further reducing any benefit and these buildings are costly.

7. If you walk the site you may also notice the elevations are extremely tricky. East of Harrison (and Washington) grade relative to the train pantograph and cables is either inverted or very tight. The Albany St bridge has very little structural depth (although none of the bridges has very much depth at the tracks). So you need to deal with this architecturally.

8. Further structural issues - if you want to include light rail or Greenway-style median (you will never have the topsoil for giant Comm Ave trees), structural depth will be a serious issue and push up costs significantly as well.



If you want to generate development there are plenty of available or underdeveloped parcels that the city can sell and would be less expensive to develop rather than incur a large upfront cost with an uncertain prospect that parcels would ever be developed.



* I know that's apostasy for AB to covering every inch of the Turnpike. But I would gladly consider a more sensible proposal of partial and incremental air rights developments such as the Columbus Center location, plus Shawmut to Harrison (post Ink Block), and something more bridge like adjacent to Albany far more practical. Limited ventilation requirements, incremental rather than one project, limited State funding (e.g. limited tax credits or none rather than large upfront construction cost), plus more sensible structurally.
 
It is well established that the cost of building over "air" is substantially higher than on terra-firma. In this section in particular, there is little to no actual earth on which to build a supporting structure, making building in this section prohibitively expensive. You can't even necessarily make up the costs with height, because the higher you go the larger a foundation you need, which is impossible balancing on some cantilevered supports over the Pike.


The genesis of the idea is to subsidize a public good (covering the Mass Pike) not through conventional means such as tax breaks or other incentives (which are having questionable results in the Fenway and the Back Bay), but through construction of a new road over the difficult-to-built-over mass Pike. Essentially a great bridge, it would take up the majority of the trench, leaving very little to cover.

Herald and Marginal would then be closed, torn up, and sold for redevelopment. At that point, they could be sold at market rate, with no tax subsidy or other incentives, to conventional developers. With only a very small percentage of the building to cantilever over the Pike, costs would be about the same as building anywhere else.

In the end, the city could probably recoup the costs of building the "bridge" boulevard over the Pike from selling the reclaimed land, and perhaps a little profit and future tax revenues. Bay Village and the South End would be reconnected for the first time since the railroad came to town. And development would happen as fast as you are seeing in the neighborhoods, instead of the snails pace associated with air rights.

In my older idea below, you can see there is a very respectable amount of buildable land that could be reclaimed (more than just the air rights). You only need around 60' for a residential building, the majority of these plots are wider than that. I'm only showing east of Tremont, but I'm confident with some clever engeneering you could do something with the part west as well. Compare the freed up yellow land to the surrounding structures, excepting the institutional buildings, they are all wider than them. Mind that my idea has a different traffic handling capacity than Shepard's iteration.
Pike1.jpg~original

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Davem,

Thank you for your thoughtful response. I think we agree on a lot of the basics, but I believe there are still problems with the economics.

No doubt air rights parcels are expensive construction and the fact virtually none are being built even during the present boom much less the last 40 years speaks to this point.

And I agree that a roadway decking is a solution which allows for much narrower or fewer foundations vs a full scale building of any size. Although it's worth noting that the landscaped (or transit) Boulevard would require a much deeper structure to span the Pike than a building of any size and might be just as problematic.

The solution you propose is to substitute for (1) expensive foundations and extensive Pike restrictions offset by a highly valued large developable area (i.e. 20 to 40 story on large floorplates) (2) for a small (but not insignificant cost) roadway that generates no direct revenue and already exists which then indirectly gives you the option to sell the land which may have value.

Think about the timing as well, the State would likely have to commit, fund and build the entire project before any developer would purchase the available land (or make an expensive binding commitment). Or the State would have to deal with a single developer as part of a single comprehensive plan which given the size and the neighborhoods would become mired in permitting. Or if the State tried to enter into say 6 smaller agreements with different developers but all to be negotiated, permitted and committed to at the same say 4 year planning horizon, the coordination would be a nightmare and never happen. Look how Hudson Yards is being financed - single developer, private financing, deferred tax credits. The City/State is only financing and building out the transit infrastructure (the 7 ext etc.).

I agree that you are switching financing mechanisms, but parcel by parcel air rights with the developer financing the large construction cost of a high-rise (not impossible, just expensive, you can definitely recoup with height) with deferred cashless tax payments, no risk to the State and incremental approach is better suited to this objective.

Even more importantly, your best argument is that you are freeing up land. This is not Manhattan, there is plenty of land in Boston. Melnea Cass, Seaport, Winthrop garage, the BRA owns 3 empty parking lots in Chinatown, adjacent to the Ink Block, the Verizon building on Harrison, tons of land on the Orange Line less than 10m from where you are proposing at Ruggles, Roxbury Xing & Jackson, the garages on Herald St, east of I-93 between the tracks.

In other words there is tons of cheaper developable land that is already owned by the developers that would likely be the choice to develop in the air rights proposal.

The land you are freeing between Clarendon and Berkeley already exists. The land on the southern side is above train tracks almost until Shawmut. The Ink Block parcels are already developed.

I agree 60' is enough for something, although your proposal is a taking I believe, which is different from the other one. And again no access road etc. I wouldn't say the cantilever won't work but it's not going to be easy or cheap.

You suggest that it would spur development but the NY Streets neighborhood, and Chinatown are already seeing that development. And there is still more land available to build.

And again the proposed building use has not been made clear in either proposal but getting a 4 story condo on a busy main road with no parking is never going to repay the cost of the roadway construction and commercial construction would have to be much higher at 50-60' to be financeable .

Finally, I agree that you get the Pike covered and it's a public good. I simply question whether it's worth this money to the State which has many other transportation and housing priorities. I love the Southwest Corridor, it would be nice to cover the Pike, but is it ruining my enjoyment of the area? stopping development in the area? depressing real estate values in the area? no.

See Curbed for the 52 Stanhope St penthouse that is offered as the most expensive in the City directly abutting the Pike. Of all the infrastructure I've lived around in my life, it is one of the least offensive.
 
Think about the timing as well, the State would likely have to commit, fund and build the entire project before any developer would purchase the available land (or make an expensive binding commitment). Or the State would have to deal with a single developer as part of a single comprehensive plan which given the size and the neighborhoods would become mired in permitting. Or if the State tried to enter into say 6 smaller agreements with different developers but all to be negotiated, permitted and committed to at the same say 4 year planning horizon, the coordination would be a nightmare and never happen. Look how Hudson Yards is being financed - single developer, private financing, deferred tax credits. The City/State is only financing and building out the transit infrastructure (the 7 ext etc.).

I agree that you are switching financing mechanisms, but parcel by parcel air rights with the developer financing the large construction cost of a high-rise (not impossible, just expensive, you can definitely recoup with height) with deferred cashless tax payments, no risk to the State and incremental approach is better suited to this objective.

Even more importantly, your best argument is that you are freeing up land. This is not Manhattan, there is plenty of land in Boston. Melnea Cass, Seaport, Winthrop garage, the BRA owns 3 empty parking lots in Chinatown, adjacent to the Ink Block, the Verizon building on Harrison, tons of land on the Orange Line less than 10m from where you are proposing at Ruggles, Roxbury Xing & Jackson, the garages on Herald St, east of I-93 between the tracks.

In other words there is tons of cheaper developable land that is already owned by the developers that would likely be the choice to develop in the air rights proposal.

I have to disagree, I believe that this would be very valuable land, due to location and proximity to transit, core of the city, etc. Much more valuable than cheaper land in Roxbury, Dorchester, etc.

In fact, I suspect that the "land making" proposal is potentially attractive enough that you could get this done by a investor driven public/private corporation chartered to "created the land". This would be much like the 19th century land fill corporations -- you created the land, build the street, you get to sell the land for development. It worked then, and should still work today this close to the urban core.
 
The value of the land is net of the development costs. Building over the tracks on small floorplates adjacent to a 25' retaining wall is expensive. And the value for the developer with low story buildings is small. The 'cheaper land' has lower construction costs but nearly as good access and would also deliver a public good. I contend that on a net basis other parcels are better value for both the state and private developers.

Furthermore, the value of the land to the State also needs to be considered net of its development costs. The public benefits by developing cheaper land with similar accessibility.

There is more available undeveloped land within 1/2 mile of here than would be gained by this proposal and its street and transport infrastructure is already paid for.

Chinatown surface lots - BRA owned (Harrison and Tyler St)
Tufts Traveler St surface parking lot
1071 Washington St - City owned?
South Bay - parcel 26a, 26b and 27 (although I think this is probably as costly a site)
Two Herald St garages which could be built up
Trinity Church and parking lot
C Mart - China Benev. Assoc.
217 to 241 Albany St - Ink Block adjacent
Ming's supermarket - Hamilton Co
Jos Quincy School sites - after new one is built
Surface lot at 131 Arlington St
MBTA building / surface lot on Randolph
Winthrop garage
Columbus Center parcels
South Station
Post Station annex

So there is plenty of land, with cheaper construction costs, similar location, generally cash positive for the state as opposed to a cost, and development no risk for the State. Develop these parcels first and then consider investing in more expensive infrastructure to spur development.

Modern permitting, environmental, traffic mitigation and development costs are far different than the 19th century. Of course it can be done, see the Hudson Rail Yards project, that doesn't mean it's good public policy.
 
Paul, I'm really not sure I understand the objection. Davem and JeffDowntown point out rightly how and why this would work. You meanwhile point to other nearby parcels where development could occur... which means what, exactly? Nobody claimed these were the last developable parcels in the city. But on the other hand the Pike trench is a significant and conspicuous gash in the urban fabric which no air-rights development since Copley has succeeded in bridging. I feel this represents a clear public good, with infrastructure costs that can be at least recouped, and perhaps even passed on to the private sector.
 
I think DaveM's plan is excellent. Also, the value of some of these lots wouldn't be limited to the return of a 4-6 story condo building with a narrow footprint; rather, many of the lots, particularly on the South side, could be combined with existing, underutilized lots for larger projects.
 
I feel this represents a clear public good

Don't forget that besides closing the gash we also get housing (desperately needed), possible retail (always nice), and property tax revenue from previously undeveloped land (always VERY nice).
 
Paperless,

I think that you're looking at this from purely a traditional cost/benefit assessment angle, which is fine. From that perspective, this project doesn't make sense.

I'm looking at it as a public good, that so happens to have the added bonus of recouping its costs. It gets rid of the Pike trench, reduces visual, air and noise pollution, rationalizes the street grid a bit in that area, and gets these parcels developed within a much shorter timescale then they would be as traditional air rights (aka, possibly never). I also think it could be used as an extension of the SWC bike path, creating a real route to south station that doesn't involve battling through traffic. The main thing is after selling off the parcels, I think you could build this at net zero. For a public good project, that's incredible.

I'd also like to thank Shepard for taking this into 3D. My nuts and bolts are nice, but it's cool to see it's potential.
 

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