Wednesday, April 25, 2007

Urban Ring Options - Detailed Maps

Bob La Trémouille reports:

1. Introduction.
2. BU Bridge / Green Line option in Cambridge.
3. Kenmore / Orange Line Option in Cambridge.
4. Boston Side.
a. General.
b. BU Bridge / Green Line Crossing.
c. Kenmore / Orange Line Crossing.
d. Need for Green Line Technology on BU Bridge / Green Line Option.
5. Summary.
6. Application to my suggestion that Harvard Allston be serviced by a Green Line Branch.

1. Introduction.

We have done a lot of discussing of the various Urban Ring options for the subway, third phase.

To clarify things, I am providing the official MBTA maps of the two crossings. First are two maps showing Cambridge impact. Alternatives 1 / 3 is the BU Bridge / Green Line technology option. Alternative 2 is the Kenmore / Orange Line technology option.

The semi-solid line on both Cambridge maps is the proposed subway alignment. Both routes have a stop under Mass. Ave. at the Grand Junction Railroad tracks. Also shown are other stops in the east part of Cambridge. Both alternatives, after the variation in crossings and related stops, have stops in the Harvard Medical Area.

The third map is a very detailed map showing the alternatives on the Boston side. It is complicated and is not ideally presented.

The maps are best viewed if you double click on them for blow-ups.



2. BU Bridge / Green Line option in Cambridge.

The BU Bridge / Green Line option continues under the Grand Junction after the MIT stop. It apparently cuts left after going under Memorial Drive, destroying the woods and then in Boston traveling under the small connector from Soldiers Field Road / Storrow Drive.



3. Kenmore / Orange Line Option in Cambridge.

The Kenmore / Orange Line technology crossing continues a little bit under the Grand Junction after the MIT stop. It then travels under the MIT playing fields and under the Charles River. It would apparently enter Kenmore Square under the eastern of the two north south side streets.



4. Boston Side.

a. General.

The dark area at the top of the map is the Charles River. Very careful viewing will identify broken lines starting at the Charles River in the left and right top areas. The two lines come together sort of in the lower left. The combined line then curves and goes to the right.

The left line is the BU Bridge / Green Line Crossing. The right line is the Kenmore / Orange Line crossing. The combined line starts on Brookline Avenue near the Beth Israel Deaconess Medical Center and curves under Longwood Avenue for the Longwood Medical Area service.


b. BU Bridge / Green Line Crossing.

The left, BU Crossing / Green Line technology, line has two oblong areas along its route.

The higher of these is a proposed station under Mountfort Street at St. Mary's Street (St. Mary's is marked above the station). The proposal calls for the Yawkey Commuter Rail stop to be moved away from Fenway Park and be located just east of this station.

Connection between the Urban Ring subway and Commonwealth Avenue's B line would be accomplished by a tunnel under St. Mary's which would let people off on the southern Commonwealth Avenue sidewalk. Travellers would then cross Comm. Ave. traffic to BU Central station.

Commuter Rail travelers from Worcester, Framingham, etc. would walk through the Urban Ring station and tunnel to the B Line for Green Line connections.

The second oblong is under Park Drive for a new Urban Ring station to be located between the current D line Fenway Park station and Beacon Street. A new C line station would be built under Beacon Street to make that connection.

c. Kenmore / Orange Line Crossing.

The right line has only one oblong / station. That station would be located under the Brookline Avenue bridge over the Mass. Pike. It would directly connect to Kenmore station on one end and Yawkey Station on the other.

In contrast to the BU Bridge crossing, this station would provide excellent connection to Fenway Park and ready transfers for hundreds of commuter rail travelers to all three green lines.

d. Need for Green Line Technology on BU Bridge / Green Line Option.

The BU Bridge crossing has to use Green Line technology. It cannot use Orange Line technology because of a sharp right turn where Mountfort Street turns to Park Drive. This turn is slightly to the right of the Mountfort station.

5. Summary.

I hope these maps are of value.

6. Application to my suggestion that Harvard Allston be serviced by a Green Line Branch.

On the first of these maps, if you look at the bottom of the map, you are looking at Commonwealth Avenue in Boston. There are a lot of T’s on Comm. Avenue, denoting Green Line B stops.

Just to the left of the crossing is a solid north-south line indicating the BU Bridge.

Just to the left of the BU Bridge can be seen the Mass. Pike and just below the Mass. Pike is another solid line.

That last solid line is the Commuter Rail line from Worcester / Framingham to Boston.

Harvard owns pretty much everything from that line going up the left side of the map.

The Green Line B branch goes up the middle of Commonwealth Avenue.

My proposal would have a branch created by putting in switches on the Green line rails just west of the BU Bridge. Tracks would be laid ABOVE the commuter rail first on Commonwealth Avenue, then on a bridge directly above the commuter rail.

The bridge would extend above the rail yard which you see on the left and then drop so that a stop for Harvard Allston could be created between Cambridge Street and Western Avenue under a street which currently connects the two. Harvard wants this street to be made a major boulevard running to North Harvard Street just south of Harvard Stadium.

The Harvard Allston spur would continue under this boulevard, under the Charles River and under JFK Park at JFK Street and Memorial Drive.

Just north of JFK park is a tunnel which has never been removed by the MBTA which connected a temporary station at the JFK School to the Harvard Station. That tunnel could create a terminus for the Harvard Allston connector which would directly connect to the underground bus tunnels at Harvard Station.