Circle Interchange

The Circle Interchange
Aerial photo of the Circle Interchange, looking southwest
Spaghetti Bowl[1]
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 (also called the Spaghetti Bowl^[1]) is an expressway interchange near downtown Chicago, Illinois. It is the junction between the Dan Ryan, Eisenhower and Kennedy expressways (Interstates 90/94 and 290). 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.

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^[2] losing a combined 25 million hours.^[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.

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 freeways is one lane wide, except for the ramp from eastbound I-290 to eastbound (southbound) I-90/94; this ramp is two lanes wide.

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.

History

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

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.^[2]

References and notes

1. ^ ^{a b} Hilkevitch, Jon (2004-12-27). "A heavy toll on RV users - I-PASS won't avert new hikes". Chicago Tribune. http://docs.newsbank.com/openurl?ctx_ver=z39.88-2004&rft_id=info:sid/iw.newsbank.com:NewsBank:CTRB&rft_val_format=info:ofi/fmt:kev:mtx:ctx&rft_dat=1073FC2460651E62&svc_dat=InfoWeb:aggregated5&req_dat=AA98CDC331574F0ABEAFF732B33DC0B2. Retrieved 2008-07-18. 
2. ^ ^{a b} 10 Pieces of U.S. Infrastructure We Must Fix Now - Brooklyn Bridge, Chicago, New Orleans - Rebuilding America - Popular Mechanics
3. ^ Traffic Congestion and Reliability: Trends and Advanced Strategies for Congestion Mitigation: Chapter 3
4. ^ Young, David M. (2005). "Spaghetti Bowl". Chicago Historical Society. http://www.encyclopedia.chicagohistory.org/pages/1179.html. Retrieved 2008-01-26. 
5. ^ UIC Historian (2006). "Chicago Circle Campus Construction". Board of Trustees of the University of Illinois. http://www.uic.edu/depts/uichistory/campusconstruction.html. Retrieved 2008-02-01. 
6. ^ "Interchanging Identities". UIC School of Architecture. http://www.arch.uic.edu/school6.php. Retrieved 2008-02-02. 

External links

• The Chicago Sun-Times Chicagopedia