Interstate 79
Raymond P. Shafer Highway

The main north-south artery for Western Pennsylvania, this Interstate is a major transportation route from Pittsburgh to Erie and points north.

Initially, this project was under the guidance of the Pennsylvania Turnpike Commission. In the early 1950s, before the Interstate Act was passed, the state proposed a system of limited access toll highways that followed the routes of the current Interstates.  Interstate 79 would be comprised of two sections:  the Northwestern Extension that would run from Pittsburgh to Erie and the Southwestern Extension that would run from Pittsburgh to the West Virginia border.  

The Interstate Act was passed on June 29, 1956 and but construction would not begin until 1961 on the section from Exit 33 to Exit 38.  In 1962, the section from Exit 33 to Exit 34 opened to traffic and construction began on the sections from Exit 30 to Exit 33 and Exit 85 to Exit 88. In 1963, the sections between the Interstate 70 interchanges, from Exit 30 to Exit 33, and Exit 85 to Exit 87 opened to traffic while, construction began on several sections:  I-70 to Country Club Road, McMurray Road to the Allegheny County line, Exit 88 to Balder School Road, and the Mercer County line to the PA 58 overpass.

In 1964, the Department of Highways decided to reroute I-70 out of Pittsburgh and onto its current alignment south of the city.  They were following the rules that the main highway goes through a city, while a even numbered loop goes around the city.  So I-279 was proposed to bypass the city while I-79 entered via the Penn-Lincoln Parkway and proposed East Street Valley Expressway.  In the same year, the section from Exit 88 to Exit 96 opened to traffic, while construction began on the sections from Exit 14 to Exit 19, Country Club Road to Exit 41, Allegheny County line to Exit 54, and Exit 96 to the Mercer County line.

In 1965, the sections from Exit 38 to Exit 41 and Exit 96 to Exit 99 opened to traffic.  The same year construction began on several extensive sections:  Exit 19 to the Washington County line, Exit 51 to the Allegheny County line, PA 58 overpass to the District Road underpass, Exit 141 to the Damsville Road overpass, Exit 166 to Exit 174, and Exit 178 to Exit 182.  In 1966, construction got underway on yet more sections:  Exit 19 to Exit 30, Exit 154 to Exit 166, and Exit 174 to Exit 178.  In 1967, several sections were completed:  Exit 14 to Exit 19, Exit 23 to Exit 30, Exit 41 to Exit 54, and Exit 99 to Exit 121 which included the cloverleaf with Interstate 80.  As those sections opened, construction on the sections from Exit 54 to Exit 57, Aleppo Township line to the Borough of Franklin Park line, and Exit 147 to Exit 154 began.  In 1968, the sections from Exit 19 to Exit 23, Exit 54 to Exit 55, and Exit 178 to Exit 182 opened while the sections from Exit 57 to Exit 60, Butler County line to Exit 85, and the Damsville Road overpass to Exit 147 began.  The final year of the 1960s saw the completion of the Exit 154 to Exit 166 section while construction began on the parts from Exit 60 to Exit 64 and Exit 66 to the Aleppo Township line.

I-79 in 1970
I-79's progress by
October 20, 1970.
(Allegheny College)

In 1970, the sections from Exit 55 to Exit 57, Exit 78 to Exit 85, Exit 121 to Exit 141, and Exit 166 to Exit 178 opened to traffic.  The same year, construction began from the Borough of Franklin Park line to the Bradford Woods Road overpass.  In 1971, construction began on the section from Exit 7 to Exit 14.  That same year saw the I-79 and I-279 designations switch routes, with I-79 now bypassing the city while I-279 would be a spur into the city from the north as the I-76 designation had been extended through Pittsburgh to end at Interstate 79.  In 1972, the sections from Exit 60 to Exit 64 and Exit 141 to Exit 147 opened to traffic while construction began on the parts from the West Virginia state line to Exit 7 and Exit 64 to Exit 66.  In 1973, the section from Exit 57 to Exit 60 opened which included the three level stack interchange with the Penn-Lincoln Parkway.  The interchange itself opened in November 1973 after four years of delays caused by a long construction workers strike and by changes in state priorities in the aftermath of Tropical Storm Agnes.  At $14 million, it was the most expensive interchange project ever built in the state at the time.  The same year, construction was extended from the Bradford Woods Road overpass to the Butler County line.  In 1974, the section from the West Virginia state line to Exit 1 opened to traffic.

The first exit numbers to appear on the 1975 PennDOT map showed I-79 with mileage based exit numbers, which in 2001 reappeared, from the Parkway West interchange north to Erie and sequential exit numbers from the West Virginia Line to Bridgeville.  The last time mileage based exit numbers were shown on I-79 was on the 1977 map.

I-79 Dedication Program
Program from the dedication on October 30,
1970.  (Allegheny College)

In 1976, the sections of Intestate 79 opened from Exit 1 to Exit 14 and Exit 60 to Exit 78 to create a seamless ribbon of expressway from West Virginia to Erie.

However, that was not the end of construction on I-79.  In 1982, construction began to extend the end of the Interstate to PA 5 which opened in 1984, and eliminated a temporary connection to Pittsburgh Avenue to the west that opened in 1975. Even though the designation ends at PA 5, the highway continues as an at-grade facility to the lakefront known as the Bayfront Parkway which opened on October 22, 1990 to spur development around the Flagship Niagara.

It was reported in 1999 that there were cracks developing on the bridge that spans the back channel of the Ohio River between Neville Island and the south shore.  The I-79 Bridge, as it is referred to, is the longest span in Western Pennsylvania.  These new cracks did not pose a threat to the span unlike another 22 years earlier.  In January 1977, a riverboat pilot noticed cracks on the underside of the then five-month-old bridge which caused PennDOT to close it for three months while repairs could be made.  The crack was in an electroslag weld between two beams, which were used on bridges at that time but no longer, was fixed along with the other welds in the bridge.  

In the spring of 2000, work began on connecting I-79 directly to the Turnpike.  The project, called the Cranberry Connector Project, consisted of building a high-speed interchange between the two Interstates with access to and from US 19. Preliminary design for the connector began in 1989, but was delayed by funding shortfalls until value engineering was used in 1997 to trim $16 million off the total cost of the project.  The former Perry Highway, then renamed Cranberry Toll Plaza, was removed and instead a mainline one was built at milepost 30 on the Turnpike where the Butler Service Plaza used to stand just to the east of Exit 28.

This project hit a little snag on May 17, 2000.  When workers began lowering the 50 ton concrete beams into place for the seven-lane PA 228 overpass, they realized something:  the beams were six inches too long and wouldn't fit.  As a result, PennDOT had to put them into storage and buy 25 new ones built to the exact specifications, at a cost of $1.6 million.  The Department of Transportation paid about $50,000 to have the beams, which were built in Erie, shipped south on I-79, trucked back north to a state maintenance storage yard off US 422 in Portersville.  With this error, the price tag of this segment of the project went from $9.7 million to $11.6 million.  

The first ramps that were constructed as a part of the project opened on October 4, 2001.  These are the ramps leading from PA 228 to I-79 southbound, and from I-79 northbound to PA 228.

Groundbreaking took place on February 22, 2002 for the final leg of the project, which was the direct connection between I-79 and I-76/Pennsylvania Turnpike.  Secretary of Transportation, Bradley L. Mallory, along with state and local officials, attended the ceremony to kick off the $44.3 million project.  This segment of the work consisted of building an off-ramp from I-79 North to PA 228 and an on-ramp to I-79 South from PA 228.  Traffic signals were installed at the end of both ramps at PA 228.  These ramps opened on October 5, 2003.  Temporary ramps between the connector and US 19 opened on November 12, 2003.  At 10:30 AM, on June 22, 2004, Secretary of Transportation Allen D. Biehler, with state and local officials, cut the ribbon which signaled completion of the project.

Groundbreaking for the final section of the Cranberry Connector
Groundbreaking for the final section of the Cranberry Connector.
(Pennsylvania Department of Transportation)

Another connection that has been lacking will be taken care of finally.  On December 9, 2002, the Southwestern Pennsylvania Commission approved shifting $6.7 million in state and federal funds to the project so construction could get under way in 2005.  Pennsylvania Department of Transportation Engineer Ray Hack said the project will take two years and cost at least $50 million.  To head west on US 22 and US 30 before the interchange, travelers had to exit and travel PA 60, which has become congested with development.  "Everybody knows the ramps are long overdue," Hack said. "People who have to use Route 60 to and from the airport face nothing but traffic lights between I-79 and the parkway."  In addition, PennDOT will widen more than one mile of the Parkway West to three lanes in each direction between the I-79/I-279 interchange and Parkway View Industrial Park.  Hack went on to say, "Someday, the Parkway West will be three lanes in each direction between Pittsburgh and the airport."  Construction began in Summer 2006 and finished in 2008 marking the completion of the interchange after 30 years.  The ramp from I-79 southbound opened on November 24 and the ramp to I-79 northbound opened on December 9 and cost $67 million.

New ramps at I-79 and I-279
Location of proposed new ramps.
The future ramp from US 22/US 30 eastbound to I-79 northbound
The future ramp from US 22/US 30 eastbound to I-79 northbound.  (Ed Szuba)
Clearing for the ramp from I-79 southbound to US 22/US 30 westbound
Clearing for the ramp from I-79 southbound to US 22/US 30 westbound.  (Ed Szuba)

Another interchange that has had problems, but was eventually corrected, was the I-70/I-79 interchange east of Washington.  PennDOT had been planning a $30 million project to rebuild the interchange and eliminate the hairpin curve where I-79 north merges into I-70 westbound.  That location had been the scene of many accidents, many of which involved tractor-trailers traveling too fast and spilling their loads as they tried to negotiate the sharp turn.  One of the youngest victims of an accident there was five-year-old Tonya Watson, of Portland, Oregon, who died when the truck her father was driving overturned on the curve, and she ended up suffocating when the padding in the sleeping bunk of the cab pressed against her throat.  After that accident, a tall Jersey barrier was installed, additional signs and rumble strips were added to warn of the sharp curve, and the speed limit was also lowered to 25 MPH.

Michael Dufalla, PennDOT District 12 engineer, said, "That's been a problem to me since they built it."  He also noted that the interchange was built to 1950s' standards.  "Rarely did people go 60 or 65 miles per hour then," he said.  "Automobiles have progressed faster than we can rehab the roads."  The project will improve access in all directions and the ramp designed to handle higher speeds.  Additional land was purchased in order to rebuild the interchange, which began in Fall 2011.  The fly-over ramp from I-79 northbound to I-70 westbound opened to traffic at 5 PM on November 16, 2013.  The $35 million project will concluded in October 2014 after rehabilitation of two bridges that run underneath the ramp, additional lighting is added, and the Interstate is milled and paved.

The January 2004 weather was not kind to a four mile section from Kirwan Heights to the Parkway West.  As happened on that latter expressway, potholes began opening up on I-79 due to the cold weather and age of the highway.  The conditions were so bad early in the week of February 1 that state police shut down two lanes for four hours.  PennDOT laid down temporary patches, but started an $93 million project to rebuild this section in August 2004 which concluded two years later.

Demolition of the guiderails on the ramp from I-79 northbound to I-279 northbound
Demolition of the guiderails on the ramp from I-79
northbound to I-279 northbound.  (PennDOT)

The S-curve located between the PA 60 and PA 51 interchanges has been the scene of several rollover accidents:  two in 1997, one in 1999, five between March and July 2002, and one in 2004.  No rollover accidents were recorded in 2000, 2001, or 2003, and none since 1996 have resulted in deaths.  When I-79 was resurfaced in 2001, a larger warning sign was installed above the lanes to warn of the winding alignment ahead and the banking changed to make it easier for vehicles to remain on the Interstate while passing through the bends.  However, the biggest change took place on May 4, 2004 when the speed limit for cars was raised to 55 MPH, while trucks remain at 45 MPH.  Alerts are broadcast on the highway advisory radio station at 1630 AM and monitoring devices were installed that notify drivers of their speed.  A poster with a picture of a truck that rolled over in the S-curve with a warning message to drivers to adhere to the posted speed limit was put up at the rest area near Collier.  Another roll-over crash took place on August 20, 2018, and another only a few months later around 5 AM on January 23, 2019 which closed the northbound lanes until 1:30 PM.

PennDOT District 11 Traffic Engineer Todd Kravits was asked about the "S" bends.  He said that there had been 22 crashes since 2014 in both directions of the Interstate in that area with 11 of those involving trucks.  Kravits went on to say, "We may be initiating a study to see if its feasible for us to straighten out the "S" bends."  However he added, that "it's never going to be a straight shot, but the curves could be a lot smoother which would make it a lot easier to negotiate through the bends."  In the meantime, work is scheduled to begin on a new high-tech alert system with new electronic signs and equipment that will measure speed and determine the type of vehicle.  If it detects a truck traveling at 55 MPH or higher, it will send out a warning to the signs along and over the roadway.  The system went into operation on February 7, 2020.

Longwall mining again began to attack Interstate 79 in September 2004 when mining activities by the Foundation Coal Corporation, now Alpha Natural Resources, began underneath segments of the Interstate south of Waynesburg in Greene County.  Mining was completed in November 2009.  The Department of Environmental Protection deemed damage to the roadway as minimal with the majority being cracking and heaving along the edges of the northbound and southbound lanes which was easily fixed by PennDOT.

The northern Ohio River crossing has not had good luck what with cracks developing after it just opened, more developing in 1999, and then came June 14, 2005.  The high heat inundating the Pittsburgh area for the previous few days caused an expansion dam on the southbound side to become dislodged and rise.  The bridge was closed around 6:15 PM with traffic detoured off at PA 65 to the Sewickley Bridge and PA 51 back to I-79, then later the detour was changed to I-279.  Repair crews spent the night repairing the expansion dam and reopened the bridge at 5 AM the next morning, while bridge inspectors used a special crane to examine the underside of the bridge to assure no other damage had occurred.

Remedying old interchange design problems seems to be on the agenda all along Interstate 79 as work began April 12, 2010 to complete ramps at Exit 88 in Butler County.  The $18 million project included construction of a new southbound on-ramp and northbound off-ramp, improvements to the original ramps, installation of sound barriers, drainage, guide rail, pavement markings, and signage, and was completed December 20, 2011.  Not all were happy with the new ramps, as one resident who lost trees to the project was the only one whose were not replaced in her neighborhood.  PennDOT officials looked into the matter, and determined that they should have been replaced and were.  Similar work began March 28, 2011 in Washington County to complete the missing ramps at the Meadow Lands interchange.  The project included construction of a southbound exit ramp to Manifold Road, Locust Avenue, and Pike Street, construction of an on-ramp to the northbound side of I-79, installation of traffic signals at the ramps, new signage, and new lighting at the ramps.  The $22.4 million project came to an end on December 27, 2012.

On the morning of February 20, two Waynesburg University nursing students got some real-world experience and then some.  Alissa Boyle and Cami Abernehty were among several students and a professor who stopped to help a Washington man who had rolled his jeep around 6 AM in Greene County.  While helping the crash victim, the three had to jumped off an overpass to avoid being hit by an oncoming tractor-trailer and fell about 40 or 50 feet to the ground.  Another student also jumped, but held on to the edge of the overpass until others could pull him to safety.

Lake-effect snow showers from Lake Erie was the cause of a chain-reaction accident around noon on February 25, 2012 in Mercer County.  The pile-up involved 30 vehicles, including two commercial vehicles, occurred in the southbound lanes at mile marker 133.  The Interstate was shut down for 10 miles in each direction for about three hours while the accident was cleared.


Weather also played havoc with the roadway in March 2017 with a major accident and a power disruption.  The 20 vehicle pile-up took place on March 3 just before Exit 105 in the northbound lanes.  White-out conditions were blamed for the initial minor accident that bloomed into a major one involving that many vehicles, while others became stuck in the median trying to avoid adding to the pile-up.  Then a week later, weather caused power lines to come down between mile marker 84 and 85 around 11 AM.  The lines were repaired and the Interstate reopened shortly after Noon.

Keeping in that same theme, during the last week of May 2019, weather was not kind to Interstate 79.  On the evening of May 29, a bolt of lightning hit a telephone pole that carries lines along PA 910 and across the Interstate at Exit 73 in Franklin Park.  That pole snapped, causing a chain reaction with the weight of the lines falling causing the poles that carry the lines across Interstate 79 to lean.  Erring on the side of caution, PennDOT decided to close the roadway northbound between Exit 68 and Exit 75, southbound between Exit 73 and Exit 68, as well as the northbound off-ramp at Exit 73 around 5:30 PM until repairs could be made.  Due to the latter, northbound Interstate 279 had to be closed at Exit 8 which caused massive traffic congestion in the area.  "We were concerned with public safety with live wires above I-79, a spokesman for the Department of Transportation said.  Penn Power crews responded and began to replace the leaning poles.  The Interstate reopened a little before 11 PM, with the exception of the northbound off-ramp which remained closed until repairs were completed which was a little after 5 AM the following morning.

When the Coronavirus, or COVID-19, pandemic swept into the country in March 2020, PennDOT took measures to stem the spread to their employees and staff.  At 12:01 AM on March 17, all rest areas and welcome centers across the state, including the ones in Greene, Allegheny, Lawrence, Mercer, and Crawford counties, were closed to the traveling public.  Also all Driver License and Photo License centers were closed for two weeks and construction projects on roads under the Department of Transportation's jurisdiction were stopped.  Hearing that construction work was halted could come as welcome news, the idea of closing down the rest areas did not sit well with truckers, trucking firms, nor some elected officials.  It was then announced that on Thursday, March 19, barricades would come down at 13 rest areas across the state, including the northbound one in Allegheny County and both in Crawford County, and they would be reopened with portable restroom facilities while the permanent facilities would remain closed.  "Every decision made has been in the interest of mitigating the spread of COVID-19 and we are constantly reevaluating our response," said PennDOT spokeswoman Alexis Campbell.  "That said, we also recognize that drivers need and deserve access to rest areas."  PennDOT announced on March 24 that an additional 10 would reopen, including the ones in Lawrence and Mercer counties.  Those as well as the ones reopened earlier would provide normal service with additional cleaning and maintenance.  An additional five were reopened on Friday, March 27 which included the rest area/welcome center in Greene County.

Exit Guide
Interstate 79 Ends
Interstate 79 Pictures
Bayfront Parkway
I-79 Interchange Browser - Tim Reichard
Interstate 79 - Andy Field/Alex Nitzman
Interstate 79 - David Steinberg
I-79 Exit 147 - David Brunot
I-79 Neville Island Bridge - Bruce Cridlebaugh
I-79 Neville Island Back Channel Bridge - Bruce Cridlebaugh
Interstate 79 Pictures - Steve Alpert
Interstate 79 Pictures - Andy Field/Alex Nitzman
Interstate 79 Pictures - Dan Garnell/Scott Steeves
Raymond P. Shafer:  Highways - Allegheny College

Southern Terminus: West Virginia state line one-half mile south of Mount Morris
Northern Terminus: PA 5/PA 290 and Bayfront Parkway at Exit 183 in Erie
Length: 183.30 miles
National Highway System: Entire length
Names: Raymond P. Shafer Highway
Pittsburgh-Erie Expressway
SR Designations: 0079
0070:  Exit 34 to Exit 38
Counties: Greene, Washington, Allegheny, Butler, Lawrence, Mercer, Crawford, and Erie
Multiplexed Route: I-70:  Exit 34 to Exit 38 in Washington
Former Designations: I-70 (1957 - 1964):  Exit 38 to Exit 59A
I-179 (1958 - 1959):  Exit 178 to Exit 180
I-279 (1958 - 1971):  Exit 59A to Exit 72
Yellow Belt
Belt System:
Exit 65 to Exit 66
Emergency: 911
Traffic Cameras:
Bridgeville North
Chartiers Creek
Prestley Road
Kirwin Heights Interchange
Thoms Run Road
Collier Avenue
Carnegie South
Ewing Road
Pittsburgh Interchange South
Pittsburgh Interchange North
West Harbison Road
PA 60
Clever Road
S-Bend Northbound Entrance
First Bend (Northbound)
Second Bend (Northbound)
Third Bend (Northbound)
Third Bend (Southbound)
PA 51
Deer Run Road
Kilbuck Street
Duff Road
Glenfield Road
Mount Nebo Road
Red Mud Hollow South
Red Mud Hollow North
Magee Road Extension
Nicholson Road
Rochester Road
Wedgewood Drive
PA 910
Advisory Radio: 1630

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Page updated October 13, 2020.
Content and graphics, unless otherwise noted, copyright Jeffrey J. Kitsko. All rights reserved.
Information sign courtesy of Richard C. Moeur.
Allegheny County Belt System shield courtesy of Bruce Cridlebaugh.
Information courtesy of the Pennsylvania Department of Transportation, Pennsylvania Department of Environmental Protection, Rand McNally, WTAE-TV Pittsburgh, KDKA-TV Pittsburgh, WPXI-TV Pittsburgh, Pittsburgh Post-Gazette, Pittsburgh Tribune-Review, Bruce Cridlebaugh, Len Pundt, Washington Observer-Reporter, and the Cranberry Patch.