Saturday, January 24, 2009


D.C. Freeway Schematic:

A basic introduction to Washington, D.C.'s truncated freeway system

Illustration: Capital Beltway with Inner System, 1971 plan
with I-95 Northeast Freeway via the Fort Drive - Northwest Branch Park route

The Washington, D.C. area’s best known road is probably that which essentially circles it, the I-495 Capital Beltway.

Washington, D.C.’s main freeways are the upside down ‘T’ of the SW-SE Freeway and the north south Center Leg, and the short stretch of I-66 which enters D.C. via the Theodore Roosevelt Bridge before heading north to end in the vicinity of the Watergate complex.

Washington, D.C.’s freeway system is highly truncated with most of it unbuilt, as marketed by numerous truncations with the northern and southern ends of the Wet Leg, the north end of the I-395 tunnel at New York Avenue, the western end of the SW Freeway at Maine Street and the eastern end of the SE Freeway at a set of underpasses beneath Barney Circle at Pennsylvania Avenue SE. These freeway segments were planned as components of Washington, D.C.’s currently uncompleted Inner Loop Freeway.

Today, the term “Inner Loop” often is used to described the ‘inner’ aka clockwise running direction of the Capital Beltway. But it was to apply it an inner loop system – a sideways figure 8 – as a hub of a system with radial spokes connecting to and to points beyond the Capital Beltway. It was to accommodate both today's Capital Beltway as well as an Intermediate Loop, as shown in the 1959 plan.

1959 plan with 3 separate northern radials

1955 Inner Loop

The Inner Loop Freeway components were planned to connect to the Capital Beltway, in Virginia with I-66 from the west, and I-95 from the southwest, and in Maryland with I-295 from the south, Route 50 from the east, and I-95 from the northeast, as readily apparent by the truncated roadways at the interchange with the I-495 Capital Beltway near Greenbelt.

Such unbuilt highways underwent significant routing and design revisions from the 1950s into the 1970s to satisfy concerns, yet were canceled outright to provide extra funding to construct the WMATA rail transit system. This is even as the transportation plans from 1962 and later included highways and the WMATA rail transit system.

1962 Railways and Highways

1971 Inner Loop system
with 1975 Virginia I-595 to National Airport
(Scott M. Kozel)

Notable amongst these design revisions to reduce local negative impacts were replacing the open trench western North Leg along Florida Ave and U Streets NW (and, east of New Jersey Avenue elevated), and 11th Street NE/SE with the K Street Tunnel and the Mount Olivet Road Tunnel with surface continuation to R.F.K. Stadium.

1955 North Leg West of the Inner Loop

1971 North Leg West of the Inner Loop

Elizabeth Rowe of the U.S. National Capital Planning Commission and opponent of the 1955 Inner Loop plan was an early promoter of the I-66 North Leg K Street Tunnel in the mid 1960s.

Washington, D.C. Freeways
Scott M. Kozel - Washington, D.C. Interstates and Freeways

I-495 Capital Beltway

Scott M. Kozel - Capital Beltway

Steve Anderson D.C. Roads

Inner Loop Components:


West Leg

SW –SE Freeway

Center Leg (3rd Street Tunnel)


North Leg - K Street Tunnel Alternative

East Leg

South Leg



I-270 (Maryland)
Scott Kozel Roads to the Future

I-66 (Virginia)
Scott Kozel Roads to the Future

I-95 (today's I-395 and Route 1) 14th Street Bridges
Scott Kozel Roads to the Future

I-95 (today’s I-395) Virginia Henry G. Shirley Memorial Highway
Scott Kozel Roads to the Future

I-295/DC 295
Steve Anderson D.C. Roads

Baltimore Washington Parkway
Steve Anderson D.C. Roads

New York Avenue - 50 (theoretical I-66)

50 - unsigned I-595 (theoretical I-66) Maryland
Scott Kozel Roads to the Future

Partially Built:

Clara Barton Parkway


Virginia Route 1 Bypass

Virginia-Georgetown I-266 Crossing

I-70S Northwest Freeway


I-70S/I-95 North Central Freeway – I-95 Northeast Freeway








1971 - 1973: Replacing the I-95 Fort Drive NW Branch Park Route with the PEPCO power line Route

1964 North Central Freeway Highway Routing Mystery- making enemies for a far more destructive and longer route


I-70S at
Friendship Heights, at the Maryland-District line

The freeway system’s earliest opposition manifested itself in NW, particularly in the area of Georgetown where the Canal Road – Whitehurst Freeway extension and Glover Archibald – Three Sisters axis crossed, and to the north.

1958-59 I-70S Cross Park Freeway

That was even as most of the dwelling displacement was to Rock Creek Park's east, through Mt. Pleasant and the along 14th Street to the intersection with the I-66 North Leg of the Inner Loop at U Street.

1958-59 I-70S east of Rock Creek Park,
interchange with I-66

That these canceled freeways – indeed freeways in general to the west of Rock Creek Park – had less impacts then those remaining under consideration after 1960 led to increased political opposition to the east, as such routes as the original North Central Freeway roughly paralleling Georgia Avenue would displace considerable more dwellings.

Just imagine-
a North Central Freeway along the Georgia Avenue corridor
right by Howard University

Yet such routings were simply unnecessary.

Washington, D.C. fortuitously has its sole north south railroad industrial corridor -- the B&O Metropolitan Branch RR/ today's WMATA above ground Red Line -- about directly in the middle between the Potomac River and the Capital Beltway’s eastern portion. It could accommodate the existing railway, the rail transit that became WMATA, and freeway.


The initial D.C. I-95 Northeast Freeway engineering study report issued in 1960, considered a variety of routings before settling upon a route preference of this railroad - industrial corridor which runs next to Catholic University of America.


As such, this corridor was proposed to accommodate a generally below grade North Central Freeway routing serving both inside the Beltway I-70S (I-270) and I-95 , accommodating a spur for the latter to and from the north-east, via the Administration of John F. Kennedy in a report dated November 1962.



Nonetheless, that proposal would be seriously undermined by the subsequent initial North Central Freeway engineering study that issued its report in October 1964; that report altogether excluded the JFK B&O railroad route with an upwards of 37 route options with many running nowhere near the railroad corridor, and with a recommended route (#11) that ran partially along the railroad but with serious deviations away with far greater dwelling displacement in Brookland, D.C., notably with the Turkey Thicket neighborhood, and particularly within Takoma Park Maryland with 471 houses in a 1.1 mile segment.



By 1966 a supplementary engineering study adhered to the 1962 Kennedy concept proposal, however that was to be politically undermined by planning organizations and officials that waffle between the 1964 and 1966 plans on account of the earlier plan's lower construction costs due to its use of sloped embankments rather then retaining walls.

A 1971 design report would work to reduce local opposition by including a lid (cap) over a length of the North Central Freeway from a few hundred feet north of Michigan Avenue southward to Rhode Island Avenue; however it would in explicitly delete the idea of such a highway (and even railroad) cover northwards alongside the main campus of Catholic University of America to Taylor Street.

1966 Proposed Air Rights Area


By 1971, with the planning refinements for reducing impacts, with the 1970 refinement of the I-95 North Central Freeway in the west Brookland area with a retaining wall (reducing the dwelling displacement from 69 to 34), along with the Inner Loop component substitutions, most notably with the I-66 K Street Tunnel, the overwhelming amount of dwelling displacement for completing the then proposed freeway system was the 1,048 or so for the North Leg’s central portion connecting the I-66 K Street tunnel east of Mt Vernon Square to the I-95 Center Leg and carrying I-95 northeasterly towards the interchange with the I-95 North Central – Northeast Freeway, the Route 50 (or I-66 eastern continuation) New York Avenue Industrial Freeway and the Inner Loop East Leg.

Of this, I48 were for the I-66 tunnel, 600+ for the I-95 North Leg, and 172 for the Mt Olivet Road tunnel area of the East Leg northern portion, with its southern portion and the New York Avenue Industrial Freeway taking 0, and the I-95 portion of the North Central – Northeast Freeway displacing 34 in D.C., and about 110 in Maryland, with the subsequent PEPCO route taking 0 in Maryland but about 25 just inside D.C. just north of New Hampshire Avenue.


I-95 PEPCO-B&O Route

Inside the Beltway I-95:
1971 PEPCO Power Line -B&O
1964-73 Northwest Branch Park - Fort Drive - B&O
1960 Northwest Branch Park - Catholic Sisters College - B&O

1973 PEPCO Power Line Inside the Beltway I-95
note sharper curve at New Hampshire Avenue

The popular anti-freeway battle cry would be “no white man’s roads through black mans; homes”.

Yet the most driven latter 1960s protesting would be for the I-266 Three Sisters Bridge in the vicinity of Georgetown University, and the I-95 North Central Freeway in the Brookland – Catholic University of American area.

This arrangement leaves a disproportionate amount of the through traffic burden in the less politically affluent D.C. SE, without extra environmental mitigation, in what may be sarcastically called "social justice".

Who Really Stopped Washington, D.C.'s Freeways

A Sampling of Attitudes Towards D.C. I-95

A Washington, D.C. Big Dig

I-395 Extension

What happens north of New York Avenue?
Today's I-395 3rd Street Tunnel, initially known as the I-95 Center Leg, ends at K Street with a transition road to New York Avenue.

Obviously this highway was intended to extend further.

Planning staring in the mid 1900s shows how this was intended.
The 1955 Inner Loop study shows this- created from connecting two separate scans.


By the mid 1960s planning looked to a K Street Tunnel as the alternative to the open trench roadway along Florida Avenue and U Street. The following illustrations show the routing evolution.

Early I-66 North Leg West K Street Tunnel proposal From the 1966 North Central Freeway Supplementary Study

I need illustrations of the proposed ramp connections at each end of this early version of he I-66 K Street Tunnel.

1967 Urban League proposal

1971 Center Leg -- North Leg Interchange

1971 I-66 K Street Tunnel

Initially the I-66 K Street Tunnel would extend all the way to the Center Leg; this was soon changed to having the cross town I-66 tunnel remain beneath K Street to the vicinity of Mt Vernon Square before turning northeasterly to follow the north side of New York Avenue.


This would provide a 10 lane cut and cover along the north side of New York Avenue, intercepting 6 lanes from the 8 lane I-95 Center Leg, and 4 lanes from the I-66 K Street Tunnel. It would provide about a 50 mph design speed through the transition radii. The I-66 tunnel segment from Mt Vernon Square to 4th Street NW would displace 148 dwellings; the I-95 tunnel segment easterly from 4th Street and New Jersey Avenue to 1st Street NE would displace 600+.

Center Leg with curved connection to North Leg East


This was the first official Washington, D.C. highway proposal since the 1983-1996 planned Barney Circle Connector, presented by the Office of the D.C. Mayor in 1996. It would extend I-395 via a 4 lane tunnel wrapping behind the rear side of the Bible Way and continuing entirely within and beneath the New York Avenue right of way with 0 building displacement, but with a relatively tight transition radii.

2002 - unofficial

I developed this concept of a two deck cut and cover tunnel with 4 lanes per direction with superior operationability geometry of a gentler transition radii, taking advantage of the convenient location of the Dunbar HS with its recreation field to there route a tunnel extending beneath O Street NW-NE to the Florida Avenue area.

This provides a 60 mph design speed, with a 95% reduction of the building displacement of the 1971 design, instead of 600+, it would be some 34 within the lower triangle between 4th, M and N Streets and New Jersey Avenue.

It would be far less disruptive to maintaining traffic during the construction phase then the 1996 design tunnel directly beneath New York Avenue.

Nonetheless it has not been formally considered.

Thursday, January 22, 2009

Tuesday, January 20, 2009

1955 Inner Loop Engineering Study

1955 Inner Loop Freeway Proposal Guide to Plates

Plate 1

Plate 3