Circle Interchange

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The Circle Interchange

Aerial photo of the Circle Interchange, looking southwest
Location
Chicago, Illinois
Coordinates: 41°52′32″N 87°38′44″W / 41.875514°N 87.645458°W / 41.875514; -87.645458Coordinates: 41°52′32″N 87°38′44″W / 41.875514°N 87.645458°W / 41.875514; -87.645458
Roads at
junction:

I-90
I-94

I-290
Construction
Opened: 1960s
Maintained by: Illinois Department of Transportation
Map

The Circle Interchange is an expressway interchange near downtown Chicago, Illinois. It is the junction between the Dan Ryan, Kennedy and Eisenhower Expressways (Interstates 90/94 and 290), and Congress Parkway. The name refers to the curving ramps that appear to form concentric rings when viewed from above, and is commonly used by local traffic reporters.[citation needed]

The interchange is notorious for its traffic jams. In 2004, it was rated as the country's third-worst traffic bottleneck, with the drivers of the approximately 300,000 vehicles a day using it[1] losing a combined 25 million hours each year.[2] In a 2010 study of freight congestion (truck speed and travel time), the Department of Transportation ranked this section of the I-290 as having the worst congestion in the United States; the average truck speed just 29.41 mph (47.33 km/h).[3]

Design

The Circle is logically a turbine interchange, with each of the four mainlines having a single entrance and exit serving both directions of the crossing highway. It does not use the quadruple-decker architecture commonly associated with stack interchanges. Instead, it has a flattened layout, using the long, curving ramps to circumnavigate the crossing of the mainlines. This results in fewer tall bridges and gives the interchange its distinctive "circle" appearance.[citation needed]

Both I-90/94 and I-290/Congress Parkway have three lanes in each direction at the interchange. Each of the ramps leading to and from the expressways is one lane wide, except for the ramp from eastbound I-290 to eastbound (southbound) I-90/94; this ramp is two lanes wide.[citation needed]

The interchange centers on Congress Parkway (the east–west surface street that is the continuation of the Eisenhower Expressway beyond its terminus several blocks east of the interchange) and extends roughly from Halsted Street on the west to Jefferson Street on the east.[citation needed]

The tracks of the Chicago Transit Authority Blue Line 'L' train pass directly underneath the center of the interchange, running in an east-west direction, as they transition from surface operation in the median of the Eisenhower Expressway, to a subway to the east of the interchange. This complicates where support columns could be located in any future construction at the interchange.[citation needed]

History

The Circle Interchange was built in the late 1950s and early 1960s, at the same time as the construction of the Kennedy Expressway.[citation needed]

The University of Illinois at Chicago is adjacent to the southwest. When the campus opened in the 1960s, it was called the University of Illinois at Chicago Circle, making it the only university in the world known to be named after a freeway interchange.[4][5][6]

Due to its congestion, the May 2008 issue of Popular Mechanics listed the Circle Interchange among their list of The 10 Pieces of U.S. Infrastructure We Must Fix Now.[1]

Future

In August 2012, the Illinois Department of Transportation (IDOT) began the planning and design phases for the potential rehabilitation of the Circle Interchange.[7] It has established a project web site, which is being used to schedule public meetings.[8][9] The April 3, 2013 Chicago Tribune featured a front-page article on the estimated $420 million project, which is slated to take four years. It began in late 2013.

References

  1. ↑ 1.0 1.1 Sofge, Erik (date unknown). "10 Pieces of U.S. Infrastructure We Must Fix Now – Brooklyn Bridge, Chicago, New Orleans – Rebuilding America". Popular Mechanics. Retrieved from http://www.popularmechanics.com/technology/transportation/4257814.html.
  2. ↑ Traffic Congestion and Reliability: Trends and Advanced Strategies for Congestion Mitigation: Chapter 3
  3. ↑ "Table 3-9. Top 25 Freight Highway Locations by Freight Congestion Index Rating: 2010". Department of Transportation. 2011. 
  4. ↑ Young, David M. (2005). "Spaghetti Bowl". Chicago Historical Society. Retrieved 2008-01-26. 
  5. ↑ UIC Historian (2006). "Chicago Circle Campus Construction". Board of Trustees of the University of Illinois. Retrieved 2008-02-01. 
  6. ↑ "Interchanging Identities". UIC School of Architecture. Retrieved 2008-02-02. 
  7. ↑ "Circle Interchange". Illinois Department of Transportation. Retrieved 2012-08-27. 
  8. ↑ Circle Interchange. Public web site. Retrieved from at http://circleinterchange.org/.
  9. ↑ Public Meetings / Hearings. Retrieved on 2013-02-22 from http://circleinterchange.org/information_center/public_meetings_hearings.aspx.

External links

Flag of Chicago
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