Saturday, September 20, 2014

Mass Pike over Charles River: Possible Street Car Spur

1. Comment.
2. Possible Streetcar (“Green Line”) Spur.
3. Other construction in the area.
a. Direct applicability.
b. Related projects.

1. Comment.

I reported yesterday that the MassDOT meeting on Thursday, September 20, 2014, announced a rebuilding which leaves room for a streetcar spur between the highway and adjacent Boston University buildings.

I got the following studious comment:


Hi.   These two new projects could include a connection from the turnpike area to the Green Line.
Recently MassDOT announced:

 Project 606541 - the rebuilding of Comm. Ave. over the turnpike by the BU Bridge.   "STREET OVER I-90 & MBTA
This project involves the replacement of the bridge superstructure along I-90 at Commonwealth Ave "

There is a also preliminary project that rebuilds the supports of the road -
Project 606538 - which "includes substructure improvements to the Commonwealth Avenue bridge over the Massachusetts Turnpike and MBTA."

Project 606541

(Click here for a glossary of terms)

Project Description:
This project involves the replacement of the bridge superstructure along I-90 at Commonwealth Ave and the repair of the deck at Carlton Street over I-90 and MBTA.

    City of Boston
    Town of Brookline

Design Responsibility: Consultant
Construction Begins: Summer 2014
Project Manager: Steven E McLaughlin [Email MassHighway]
Estimated Total Contract Cost: $69,850,126.50
Estimated Total Federal Participating Construction Cost: N/A
MassHighway District: District 6
Current Status: This project has been advertised for construction bids. (as of 05/10/2014)


I will give a bit more detail as to the possible line, and then go into related projects.

2. Possible Streetcar (“Green Line”) Spur.

I published a very detailed photo analysis of the area the route could be created at

This is an on the ground analysis.

I have presented two relevant maps.

The first focuses on this area, the “viaduct” area which is being rebuilt, and whose location is crucial to any Green Line Spur.

The green line spur would come off the raised Commonwealth Avenue bridge over I90 and the commuter rail, lower to a comparable height to the highway and BU’s buildings, and proceed between the two until you get into the primary I90 / rail yard area, the future Harvard Medical School plus.

The first map shows how the spur would connect to Kenmore Square / Kendall Station.

The second map focuses on the Harvard Medical School area, including the viaduct.  A stop would be viable for Boston University’s new high rise dormitories and for Agannis Arena.

A Green Line spur could be run through the Harvard Complex, with a stop for that complex.

Going beyond the complex, it would have great neighborhood value by being run under North Harvard Street with stops at Cambridge Street and Franklin Street.  It could proceed further with a stop for Harvard Business School / Harvard Stadium.

It would then go under the Charles River and connect to busways which are part of the Harvard Station by a tunnel which continues to exist after the 1978 reconstruction of Harvard Station.  Access would be readily available to the bus tunnel complex in a stub end arrangement.

The need for a stub end arrangement adds a requirement for a layover facility under fields owned by Harvard University on either side of North Harvard Street, before crossing the Charles River.

MassDOT has a useful fact sheet on line at

3. Other construction in the area.

a. Direct applicability.

Here is one of the photos on the link I provided above,  Greater detail can be obtained at that link.

The photo is taken standing on the Commonwealth Avenue bridge over I90 / Mass. Pike in the middle of the existing streetcar / Green Line tracks.

A separation in the bridge structure starts at the left about a quarter of the way up on the photo.  The separation proceeds diagonally to the right.  If you look very carefully, a companion separation starts at the end of the concrete divider on the left.  It also runs to the right.

The area between these two separations is the bridge over the commuter rail / main line to Worcester / Framingham.

The point where the camera is standing is close to where a switch would have to be installed for the Green Line spur.

The camera is standing on the bridge above I90 / Mass. Pike.  The spur would go off the Commonwealth Avenue bridge above the commuter rail.

The buildings to the right are the Boston University buildings which follow the Mass. Pike. viaduct.  The viaduct rises so that the commuter rail goes under the viaduct until the right of way widens again.

The Green Line spur would be built between these buildings and the Mass. Pike viaduct.

b. Related projects.

The construction which the writer mentions at the beginning of this report seems to come to the point where the camera is, and up to the first divider.

Mention is made of Carlton Street.  The photo is taken not far to the west of where the highway on the BU Bridge crosses Commonwealth Avenue.  Carlton Street is the next street to the east of the BU Bridge / Commonwealth Avenue intersection.  Boston being Boston, its name changes between Commonwealth Avenue and the Charles River.

The BU Bridge / Commonwealth Avenue road complex is a very large, very complicated traffic circle / rotary which extends to various other local roads.  And the changes coming are very complex as well.

Interestingly, running a Green Line spur off at this point would be much less complicated with regard to the highway traffic than are the multiple changes which are in process.  The one real complication would be a need to allow for the spur in traffic light operation.

Any actual construction on a Green Line spur would not come until after the rebuilding of the Mass. Pike viaduct, although there clearly could be savings by combining the projects.

Harvard will not be building in the Mass. Pike / rail yard area for at least ten years, according to their various projections.  Nevertheless, service of a Green Line spur could be a value to the neighborhood and to Harvard’s construction at North Harvard and Western, plus to the Harvard Business School / Harvard Stadium area.

Going forward with the BU Bridge / Commonwealth area Avenue projects will, at minimum provide the same sort of stability to these bridges as would be provided to the Mass. Pike, and would definitely simplify construction of a Green Line spur.

I am not specifically familiar with plans for the area of Commonwealth Avenue above the commuter rail.  It is highly likely that the plans the writer presents go into that area.  It is a relatively small area and certainly, I should hope, is part of the BU Bridge / Commonwealth Avenue related projects.  The wording of the announcement reflects naming confusion which is normal when referring to transportation entities in the Boston area.  The commuter rail is part of the MBTA and, thus, is likely to be part of this project.

The discussions of the plans for the area gave no indication or reason to think that significant changes are intended.