Interstate 86 (Eastern)
Overview
Interstate 86 follows the corridor along New York Route 17 / Southern Tier Expressway, which was given high priority status in 1998. Designated in 1999, I-86 extends from just east of Erie, Pennsylvania across the Southern Tier of New York to the state line at Waverly. A second section runs along NY 17 from I-81 in Binghamton east ten miles to Windsor. Awaiting upgrades to Interstate standards, the remaining portion of the route is signed as NY 17. Specifically, key improvements are required in the Binghamton and Catskills areas.
Ultimately, Interstate 86 will be signed across the entire Southern Tier, from Interstate 90 in Pennsylvania to I-87 (New York Thruway) at Harriman, New York. Locales served by the highway include Erie, Jamestown, Olean, Corning, Elmira, Binghamton, the lower Catskills region and Middletown. The entire route is known as the Daniel Patrick Moynihan Interstate Highway (per SAFETEA-LU Section 1929).
High Priority Corridor
Interstate 86 in Pennsylvania and New York is part of High Priority Corridor 36: New York and Pennsylvania State Route 17.
Parallel U.S. Routes
Interstate 86 does not follow any specific U.S. route with the exception of a small portion of U.S. 6 near the eventual east end.
History
Interstate 86 was originally established by the American Association of State Highway and Transportation Officials (AASHTO) on June 23, 1969 along a freeway corridor connecting Hartford, Connecticut with Sturbridge, Massachusetts. This was previously designated as I-84. Beginning at I-91 near Wethersfield, I-86 overlaid a portion of the freeway along Connecticut Route 3 (former I-491) to the freeway on Route 2 at East Hartford, with an unconstructed section extending northeast to meet I-84 at Manchester. I-86 followed I-84’s course from this point northeast along the Wilbur Cross Highway into Massachusetts, ending at the Massachusetts Turnpike (I-90) north of Sturbridge. With I-86 overtaking the former route of I-84 from Manchester, I-84 was redirected eastward from I-86 along a freeway to Bolton, and ultimately toward Providence, Rhode Island.
The section of Interstate 86 that replaced I-491 between Wethersfield and I-84 at Manchester was decommissioned by AASHTO on July 13, 1976. Cancellation of the freeway from Route 2 northward through Glastonbury and East Hartford preceded the removal of I-86.
Signs for I-86 remained posted along the Wilbur Cross Highway between I-84 at Manchester and Massachusetts until plans for the extension of I-84 to Providence were officially dropped. I-84 was reestablished along its pre-1969 course while I-86 was removed altogether. The freeway spur between Manchester and Bolton was assigned as I-384. AASHTO approved these changes on May 23, 1984.
The I-86 designation in upstate New York was approved by AASHTO on November 6, 1998 as a 430 mile long route, with the stipulation that it be signed as a future corridor until the various segments of the freeway were brought up to Interstate standards. Completion of the Southern Tier Expressway (NY 17 and PA 17) occurred at a ribbon cutting ceremony held by the governors of New York and Pennsylvania on October 2, 1997. Work finished included the $19.1 million construction of 9.3 miles of the two westbound lanes from Sherman, New York to the Pennsylvania state line and $14.9 million in construction on the seven mile stretch through Erie County. The two lane section of NY 17 in western New York was finished in the early 1980s.9 The westernmost 177 miles of the route in New York to Exit 48 in East Corning was officially upgraded to Interstate 86 on December 3, 1999 following dedication ceremonies held in Belfast and Corning.6
Within the village of Painted Post, Interstate 86 meets the north end of both I-99 and U.S. 15. Originally constructed in the late 1950s as a traffic circle, the exchange joining U.S. 15 and NY 17 was converted to a diamond interchange in 1987.
In September 1997, studies began on ways to improve the interchange and the nearby U.S. 15 ramps at Gang Mills. The New York State Department of Transportation (NYSDOT) followed with preparations on the Draft Environmental Impact Statement (DEIS) in October 1998. This document was complete by July 6, 2001. “Alternative 14” was selected as the preferred alternative by August 22, 2001. This option was modified after receiving input from the public in a December 6, 2001 Public Information Meeting.
Allowing the department to proceed with the final design for the project, the Federal Highway Administration (FHWA) gave approval to NYSDOT on June 3, 2002. Construction upgrading the exchange into a high speed directional T interchange proceeded. Costing $41 million, the first phase of the project commenced in November 2003. It included work to upgrade U.S. 15 to Interstate standards and build the diamond interchange at Hamilton Street.1 With $11 million in work running through Spring 2005, the second phase reconstructed a two mile stretch of I-86 through the interchange with U.S. 15 and rebuilt the railroad bridge over the Conhocton River.1 Focused on building the flyovers between the two freeways and ramps to Robert Dann Drive, the third and final phase started in Spring 2005. Work ran through August 13, 2008, when a ribbon cutting ceremony was held to celebrate the finish of the $141 million interchange.8
In February 2004, the FHWA approved the addition of eight more miles of I-86, extending the Interstate from Corning east to NY 14 / Exit 52 in Horseheads. Upgrades from Horseheads east to Exit 56 in Elmira resulted in the signing of the next section of I-86 on March 28, 2008.7
The Southern Tier Expressway east from Exit 56 in Elmira to Exit 60 at Waverly and South Waverly, Pennsylvania was incorporated as Interstate 86 on July 31, 2013. Further east during the Summer 2005, work upgrading NY 17 around Owego and also between Windsor and Hancock commenced.5 Funds for this along with other sections of future Interstate 86 were allocated in the 2005 SAFETEA-LU. The stretch from Waverly to Exit 67 awaits I-86 designation, while work through Binghamton remains under construction.
East from Interstate 81, a 9.9 mile long section between Kirkwood and Windsor was designated I-86 on May 1, 2006 (AASHTO approved this in May 2008). Beyond there, the 121 miles to Harriman vary between sections ready for designation and those still with at-grade intersections.7
Route Information
Mileage
Pennsylvania – 6.99
New York – 216.40
Source: December 31, 2021 Interstate Route Log and Finders List
I-86 Annual Average Daily Traffic (AADT)
Source: Statewide Traffic Volume Map 2017 (PennDOT)
NYS Traffic Data Viewer 2016 AADT
East of the original circle interchange between the Southern Tier Expressway and U.S. 15 at Painted Post, NY 17 defaulted onto Dennison Parkway, a congested route through Downtown Corning.
Major Projects
Between 2001 and 2009, NYSDOT upgraded various segments of NY 17 to Interstate standards. With the western segment of NY 17 between Erie and Corning already Interstate standard, attention was directed toward the central and eastern segments. This included required improvements at Elmira, the “Kamikaze Curve” in Binghamton, and near the Catskills Mountains. NYSDOT anticipated that this entire corridor would meet Interstate standards and be fully signed as Interstate 86 by 2009. The total cost to upgrade NY 17 to Interstate 86 was expected to run between $700 to $800 million. Ted Bennett, an I-86 Chairman, hoped to see the entire I-86 project complete by 2008. He believed that if completed by that date, the region would benefit in $3.2 billion growth.2
Work to upgrade Interstate 86 in Chemung County was completed by November 2012. Included was a $7.96 million interchange built at Kahler Road, which opened after two years of work on July 7, 2004.4 Construction to address the problem at Kamikaze Curve, the site where Interstate 81 and NY 17 overlap north of Downtown Binghamton, was to go to bid in May of 2006 (the project was eventually let on September 15, 2011). Roadwork on the $90 million project was to begin three months later and take about two years to complete.3
Split into separate phases and costing $148 million, The Prospect Mountain project, includes work to reconstruct NY 17 to Interstate standards from Exit 72 (Mygatt Street) to NY 7 (Exit 4 on the overlap with I-81). Construction reconfigured Exit 72, replaced bridges over the Chenango River and redesigned the interchange with NY 7. The majority of work ran through December 31, 2015.
Phase II of the Prospect Mountain Interchange Reconstruction started on May 15, 2016 with an original completion slated for December 31, 2020. Substantial completion was estimated for March 1, 2020. Work during this phase included reconstructing Exit 4 with new bridges and ramp improvements, and additional bridge replacements along NY 17.10
Highway Guides
East End
– South Waverly, Pennsylvania
Future East End
– Harriman, New York
East at
Former East End
– Elmira, New York
East at

This shield assembly marked the temporary end of Interstate 86 shield at the Chemung/Steuben County line. The ensuing stretch of NY 17 east to NY 14 was added to I-86 in 2004. Photo by David Greenberger (04/00).
West at
West End
– Greenfield Township, Pennsylvania
West at
East at
Throwback –
at 

Prior to the establishment of Interstate 86, the freeway east from I-90 was part of multi state route 17. The original PA 17 connects Blain and Liverpool to the north of Harrisburg. Photo taken by David Greenberger (07/30/98).

Posted for a short period of time, this shield assembly acknowledged the previous route number of I-86 in Pennsylvania. Photo taken by David Greenberger (04/00).
West at
Sources:
- “I- 86 , Rt. 15 interchange under way.” The Leader (Corning, NY), January 7, 2004.
- “Route 17 And Interstate 86 Plans.” WBNG-TV (Binghamton, NY), October 2, 2003.
- “Kamikaze Curve fixes won’t affect homes, park.” Press & Sun-Bulletin (Binghamton, NY), October 3, 2003.
- “Kahler interchange grand opening today” The Leader (Corning, NY), July 7, 2004.
- “Ten-mile I-86 segment near wrap-up: Group updated on progress, costs.” Binghamton Press & Sun-Bulletin (NY), April 8, 2005.
- “Long Stretch of Route 17 Becoming I-86 Today.” The Buffalo News, December 3, 1999.
- NYSDOT | I-86 – Project Map.
- “Interchange complete” The Leader (Corning, NY), August 14, 2008.
- “Governors Rejoice As Highway’s Final Section Opens.” The Buffalo News (NY), October 3, 1997.
https://www.dot.ny.gov/prospectmountain.
Page updated May 27, 2022.