Tuesday, March 01, 2016

Renewed Silliness To Remove SE Freeway

disregarding the recent 11th Street Bridge replacement with its new ramp connections to the DC 295 Anacostia Freeway to and from the northeast.

via an article appearing February 29, 2016 in The Washingtonian "Let's Tear Down The South East Freeway And Build A New Neighborhood"

http://www.washingtonian.com/2016/02/29/southeast-freeway-development-construction-navy-yard-dc-neighborhood/

makes an interesting juxtaposition with the accompanying simplistic freeway removal ideology to discourage use of the New York Avenue corridor and the Center Leg and thus shift traffic to the SE Freeway-11th Street Bridge-DC 295 Anacostia Freeway combo.




The article is authored by Dan Reed, who studied for a Masters degree at the University of Pennsylvania, where he, with colleagues Susannah Henschel and Matt Wicklund, explored the possibilities and impacts of removing urban freeways,  particularly regarding Washington, D.C.'s  Southeast-Southwest Freeway, working with the National Capital Planning Commission.  He writes the following, which contains a number or serious flaws:
The Southwest Freeway, which carries a significant amount of traffic between the Potomac River and Fourth Street, Southwest, probably couldn’t be removed without overburdening the local street network. By the time it changes to the Center Leg Freeway and then to the Southeast Freeway, at South Capitol Street, the roadway carries a third fewer cars and could be replaced with a surface street that handles some of the traffic, with M Street, Southeast, and Pennsylvania Avenue picking up the excess. Biking and rapid transit could take care of the rest.
The amount of traffic upon the initial- western- segment of the Southeast Freeway is destined to carry significantly more traffic with the recent 11th Street Bridge replacement project that added new ramp connections on its southern end directly into the DC 295 Anacostia Freeway heading to and from the north-east, thus establishing a seem-less through D.C. connection.
The freeway changes dramatically along its path—sunken below street level here, rising onto an elevated there—so my colleagues and I developed three different treatments. At Fourth, Seventh, and Tenth streets, Southwest, the sunken Southwest Freeway is crossed by bridges. We thought about building a big cap over the freeway here, like Boston’s Big Dig, but decided it would be too expensive for the limited amount of new space it would create. Instead, we expanded each bridge to create a platform for small retail buildings, sort of like the Ponte Vecchio in Italy. They would help connect the north and south sides of the freeway visually for those crossing the bridges, while new retail could draw more street life to an area that has very little today.
The freeway is in a trench as it crosses 10th and 7th Streets SW, before rising to an elevated berm to the east thus crossing over 4th Street SW- thus the above statement is factually incorrect about the freeway being sunk below the 4th Street crossing.

How would a cap above the existing sunken segment be too expensive?  Other cities have had far more extensive cut and cover freeway projects, yet somehow this is "too expensive" for such a freeway within Washington, D.C., the Nation's Capital.  Rather, this would be a good time to remove the bottleneck with its dangerous two into one lane merge with the on ramp from Main Street, by replacing the existing retaining wall which is not designed to support a tunnel roof, with a new wall set out further to the south, allowing adding a couple lanes per direction, at the expense of a row of townhouses built in 1999 too close to the freeway- a mere 16 feet or so from the existing retaining wall.  This would be necessary to facilitate construction staging for the removal and replacement of the elevated segment to the east with a new lowered cut and cover tunnel segment.
Farther east, where I-395—now the submerged Center Leg Freeway—bends north toward New York Avenue, we’d build a platform, like the Capitol Crossing development, and place new retail, office, and apartment buildings atop it, reconnecting local streets that currently dead-end at the freeway. In the space where the 395/695 interchange now takes up nearly three square blocks, we’d create a grand new public square, similar to Farragut Square, granting this area much-needed open space.
This disregards that the freeway transitions from a trench at 7th Street SW to an elevated berm by the time it crosses 4th Street SW.   Any new platform to reconnect local streets, and such a "grand new pubic space" absolutely requires not simply covering an existing freeway segment but rather its removal and replacement with a new set of roadways constructed at a lower elevation.
East of there, we’d eradicate the Southeast Freeway entirely. Before the 1960s, Virginia Avenue—which still exists in fits and starts around Foggy Bottom and L’Enfant Plaza—was a broad boulevard not unlike Pennsylvania or Massachusetts Avenue. Our design puts it back. The new street would extend from just east of South Capitol Street to the 11th Street Bridge and all the way to the Anacostia, where it would end in a new waterfront park.
This disregards the above stated need to completely reconstruct the eastern portion of the SW Freeway at a lower elevation, as well as the recent 11th Street Bridge replacement project with its new ramp configurations making this a continuous through D.C. freeway route.   Without such a reconstruction, his platform atop the freeway would have to be likewise elevated, could not restore the street grid as the elevated highway would still be in the way, and would require a ramp to transition from the elevated freeway to the restored Virginia Avenue street level boulevard.

The idea of a restored boulevard could actually make sense if built atop a SW-SE freeway reconstructed underground.

Because of the need to maintain traffic throughout the construction project, the way to do this would be by a staged program:

- first constructing a parallel tunneled freeway facility, starting with a Washington Channel Tunnel akin to the 2008 U.S. National Capital Planning Commission proposal, continuing east beneath G Street SW-SE to Virginia Avenue, dipping under the new railroad tunnel, to a temporary merge into the SE Freeway, together with tunnel connections to the north along the Center Leg beneath 2nd and 3rd Streets.  This G Street Tunnel would be two levels, eastbound atop westbound.  Once completed, open the G Street Tunnel to SW-SE Freeway traffic heading to the 11th Street Bridges.

- secondly, remove the row of townhouses closest to the SW Freeway's southern side between 10th and 7th Streets SW, excavate that area, build a new retaining wall designed to support tunnel roof, framing additional freeway capacity, and continue this east, crossing beneath 4th Street SW, to the existing ramp to the Center Leg, and perhaps with an extension further east squeezed alongside the existing elevated SW-SE Freeway to minimize housing displacement, before merging to the east with the new G Street Tunnel to the existing SE Freeway.  Subsequently begin closing and removing the elevated SW-SE Freeway, and start constructing the underground replacement.  That could ultimately be shifted slightly southwards to improve the geometry of the connections with the Center Leg.  And it all would be opened together with the direction of the G Street Tunnel from the 11th Street Bridge. 

- subsequently, finish the new 2nd and 3rd Street Tunnels along the Center Leg.  Before these could be used as a through route, they would need a merge into northbound I-395, which would occur within a tunneled extension to the north-east, employing not the substandard geometry of the 1996 Ron Linton plan's curved transition at the rear of the Bibleway Church complex and then directly beneath New York Avenue, but rather a gentler radii curve arcing beneath the New Jersey Avenue/N Street intersection and the Dunbar field, to a straight line continuation under O Street NW/NE.   Optionally, build a temporary connection to New York Avenue near the location of the Fed Ex building.  Or expedite a permanent underground tunnel box freeway extension to the east along the northern side of New York Avenue featuring parallel box for a new WMATA rail transit line, and a decking over of the railroad chasm, with a new linear park and city scale real estate development atop; such would be easier than constructing that tunnel directly under New York Avenue as discussed during the late 1990s and early 2000s, and far more potentially profitable with the line of new real estate development.  

- This tunneled extension from the Center Leg to alongside New York Avenue should have design flexibility to ultimately accommodate tunnel box versions of freeway connections to the north along the Grand Arc reconstruction of the B&O Metropolitan Branch with a vast linear park atop, to an East Leg to RFK Stadium and the eastern end of the SE Freeway as a cover-way essentially extending the structure of Barney Circle, and for a tunnel directly under New York Avenue

Once the New York Avenue corridor box tunnel freeway is completed to Maryland Route 50, traffic could be shifted from the antiquated DC 295 Anacostia Freeway to facilitate the latter's reconstruction as a modernized cut and cover facility bring its specifications up to date while permitting opening up local access to the Anacostia River waterfront.

The failure of the Dan Reed article in addressing any of this, speaks volumes as to the deficit of thought with much of the trendy [anti] intellectualism of the ideology of outright freeway removal

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