Springfield Interchange

Springfield Interchange

The Springfield Interchange as of 2007. In 2012, ramps from the I-95 HOV lanes directly to the Capital Beltway (not shown) were built.
Location
Springfield, Virginia
Coordinates: 38°47′28″N 77°10′34″W / 38.791°N 77.176°W / 38.791; -77.176Coordinates: 38°47′28″N 77°10′34″W / 38.791°N 77.176°W / 38.791; -77.176
Roads at
junction:		 I‑95
I‑395
I‑495
SR 644
Construction
Type: Interchange
Constructed: 1960s
Maintained by: VDOT

The Springfield Interchange, also known as the Mixing Bowl,[1][2] is the interchange of Interstate 95, Interstate 395, and Interstate 495 in Springfield, Virginia, outside of Washington, D.C. The interchange is located at exit 57 on the Capital Beltway and exit 170 on I-95.

Some people, including many Washington-area media sources, refer to this interchange as the "Mixing Bowl" because, prior to the reconstruction, local and long distance travelers shared the same lanes and travelers had to merge to the right or left to reach the correct lanes for their destination. The last of this weaving and merging was eliminated on April 21, 2007. The interchange is one of the busiest highway junctions in the U.S., serving about 430,000 cars per day.[3]

History

The interchange was originally built in the 1960s as a simple interchange between I-95 and the Capital Beltway. At the time, I-95 was expected to go through the District of Columbia. After community opposition prevented its construction through the city in 1977, I-95 was shifted to the eastern portion of the Beltway, between Springfield and College Park, Maryland, eliminating the I-495 designation there (although that designation was reinstated in 1989). Because of this route change, all traffic continuing on I-95 through the Washington area was exiting at Springfield through an interchange not designed for that purpose. By early 1970, there were 150,000 vehicles per day traveling through the intersection. Thirty years later, that number had more than doubled, with the effect that vehicles "traveling along the East Coast's main north–south artery [had to] be funneled through the ordinary exit ramps at Springfield, routinely causing backups several miles long."[4]

A study by the National Highway Traffic Safety Administration determined the interchange to be the site of 179 crashes between 1993 and 1994—more than any other spot on I-95—and found that the number of ramp accidents was more than double that of any other Beltway interchange.[4]

Major reconstruction (1999–2007)

In March 1999, the Virginia Department of Transportation (VDOT) began an eight-year, seven-phase reconstruction project, which also involved the reconstruction of the I-95/Route 644 interchange. The project was one of the largest highway construction projects in the U.S., costing $676 million.

Springfield Interchange in 2006. The ramp carrying traffic from I-95 north to I-495 north is no longer off this roadway, but rather is the ramp to the right.
Overhead signs (installed in late 2014) along I-495 approaching the interchange from the northwest. Since 2012, commuters can access the I-95 Express Lanes directly from the Beltway.

Phase 1

Completed 1999

Phases 2 and 3

Completed November 2001

Phase 4

Completed October 2004

Phase 5

Completed May 2004

Phases 6 and 7

Completed July 2007

Upon completion, The Washington Post noted: "The project began in 1994 with a budget of $241 million. By 2002, it had nearly tripled, to $676 million, and a federal audit found that VDOT had underestimated costs and mismanaged funds. As recently as [2005], the project was months behind schedule, and managers predicted that it would not be completed on time. But VDOT officials pressured the primary contractor, including issuing a formal default letter, and work was put back on schedule without adding costs."[7]

The project was completed on time in July 2007. The new interchange has 50 ramps and bridges, is 24 lanes at its widest point, and has a capacity of 500,000 vehicles per day.[8]

Phase 8

Phase 8 involved the construction of ramps connecting Shirley Highway's reversible center carriageway (HOV lanes) to the Capital Beltway. It was originally planned to be part of the Springfield Interchange Project but, due to cost overruns, was moved to the future Capital Beltway widening project, which was to include HOV lanes on the Capital Beltway. Phase 8 was subsequently deferred when the Beltway widening was delayed. Phase 8 was eventually constructed as part of the I-495 Express Lanes (high-occupancy/toll lanes) project and the Phase 8 ramps opened to traffic on November 17, 2012.

Other improvements

To aid commuters during construction, VDOT added 5,000 park-and-ride spaces, created a vanpool program, increased safety patrols to clear breakdowns, created a project web site, and distributed notifications of lane closures via an email list. VDOT also maintained a storefront office in the Springfield Mall.

Earlier uses of the "Mixing Bowl" name

The term "Mixing Bowl" was previously used to refer to the interchange between I-395 and State Route 27 in Arlington, near the Pentagon and Arlington National Cemetery; this interchange, like the Springfield one, contains a large number of lanes and ramps. However, most news reports on the Springfield Interchange refer to it as the "Mixing Bowl", and the term has become generally accepted.[1] The other interchange is now known as the Pentagon road network.

References

  1. 1 2 "VDoT Springfield Interchange website search results for "Mixing Bowl"". Virginia Dept. of Transportation. Archived from the original on September 28, 2007.
  2. ↑ "ASCE Virginia History and Heritage". roadstothefuture.com. Retrieved December 4, 2010.
  3. ↑ http://www.springfieldinterchange.com/ Springfield Interchange Improvement Project Archived August 22, 2005, at the Wayback Machine.
  4. 1 2 Alan Sipress; Alice Reid (January 3, 1999). "Untangling Washington's Worst Interchange". Washington Post. p. A1.
  5. ↑ New Beltway Outer Loop Ramp to I-395 North Opens Thursday Morning
  6. ↑ New Ramp Opening: I-495 East (Outer Loop) to I-95 South
  7. ↑ Eric M. Weiss (July 18, 2007). "Celebrating Mixing Bowl's Big Makeover: Dedication Is Set for Today At Revamped Interchange". Washington Post. p. A01.
  8. ↑ "At a Glance". The Washington Post. July 18, 2007. p. A12.
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