Interstate 476
Interstate 476 (I-476) is a 131.51-mile (211.66 km) auxiliary Interstate Highway entirely within the U.S. state of Pennsylvania.[1] The route begins at an interchange with Interstate 95 in Ridley Township, Delaware County, and heads north through the Philadelphia suburbs.[2] Its southern segment, known as the Mid-County Expressway or Blue Route, spans approximately 21 miles through Delaware and Montgomery counties to connect with the Pennsylvania Turnpike (Interstate 276) in Plymouth Meeting; this section acquired its nickname from the blue line used to denote it on 1960s planning maps.[3][4] North of Plymouth Meeting, I-476 follows the tolled Northeast Extension of the Pennsylvania Turnpike for about 110 miles, serving as a key north-south corridor through the Lehigh Valley and Pocono regions before terminating at an interchange with Interstate 81 near Clarks Summit in Lackawanna County.[5] Designated as part of the Interstate Highway System, I-476 facilitates commuter and freight traffic bypassing central Philadelphia, with the Blue Route portion completed in 1992 after decades of planning and legal challenges over environmental impacts and alternative alignments.[3][4] The Northeast Extension, operational since 1957 as an extension of the original Pennsylvania Turnpike, imposes electronic tolls managed by the Pennsylvania Turnpike Commission, while the southern Blue Route remains toll-free under Pennsylvania Department of Transportation jurisdiction.[5] Ongoing improvements, including flex lane additions between U.S. Route 1 and Interstate 95, aim to alleviate congestion on the heavily traveled southern section.[2]Overview
Route Summary and Design Standards
Interstate 476 (I-476) spans 131.51 miles in Pennsylvania, extending from its southern terminus at Interstate 95 (I-95) in Ridley Township, Delaware County, northward through Delaware and Montgomery counties to the Pennsylvania Turnpike mainline (Interstate 76/Interstate 276) in Plymouth Township, Montgomery County, and continuing as the Northeast Extension through Bucks, Lehigh, Carbon, Luzerne, and Lackawanna counties to its northern terminus at Interstate 81 (I-81) near Clarks Summit.[6] The route functions as an auxiliary interstate to I-76, providing a limited-access bypass of central Philadelphia and serving commuter, commercial, and recreational traffic to the Lehigh Valley and Poconos regions.[7] The Mid-County Expressway portion, locally known as the Blue Route, covers about 20 miles from I-95 to the Pennsylvania Turnpike and consists of four lanes south of Pennsylvania Route 3 (PA 3) with six lanes to the north.[7] This section incorporates 12-foot-wide travel lanes, 10-foot-wide shoulders, variable median widths, and a 65 mph design speed, constructed to Interstate Highway standards with full grade separation and controlled access.[7] The Northeast Extension, approximately 110 miles long and operated as a toll facility by the Pennsylvania Turnpike Commission, generally features four travel lanes throughout, with 12-foot lanes and 10-foot shoulders in keeping with turnpike design criteria aligned to federal interstate specifications for divided, limited-access highways.[7] Design standards for I-476 emphasize safety and capacity, including concrete or asphalt pavements designed for high-volume traffic (exceeding 50,000 vehicles daily in southern segments), rumble strips on shoulders, and ongoing upgrades such as variable speed limit systems to adapt to congestion and weather.[8] Posted speed limits are typically 65 mph, though reduced in construction zones or interchanges, with the entire alignment meeting Federal Highway Administration criteria for interstates: no at-grade crossings, minimum vertical clearances of 14 feet over roadways, and bridges engineered for Interstate loading standards (HS-20).[7]Strategic Importance and Traffic Patterns
Interstate 476 functions as the dominant north-south artery in eastern Pennsylvania, spanning from Interstate 95 near Chester to Interstate 81 near Clarks Summit and providing a high-capacity, limited-access alternative to urban routes through Philadelphia. This configuration supports efficient freight transport between Delaware River ports and Lehigh Valley logistics centers, which handle significant warehousing and distribution for regional manufacturing, while also enabling commuter flows from Philadelphia suburbs to employment hubs in Allentown and Bethlehem.[3] The highway's integration with the Pennsylvania Turnpike system enhances connectivity to broader Northeastern markets, mitigating bottlenecks on parallel arterials like U.S. Route 422 and promoting economic activity in areas with high industrial density.[9] Traffic volumes peak in the southern Mid-County Expressway segment (the "Blue Route"), where average annual daily traffic (AADT) reaches 86,800 to 108,000 vehicles per day north of MacDade Boulevard, driven by suburban commuters and regional travel.[10] Along the Northeast Extension, volumes taper northward, with mainline through traffic estimated around 80,000 to 100,000 AADT in southern portions, declining to 20,000 to 40,000 further north amid fewer local origins and destinations.[11] Interchange data from 2023 illustrates this gradient, as shown below:| Interchange | Milepost | Total AADT | % Trucks |
|---|---|---|---|
| Lansdale | A 31 | 32,519 | 12 |
| Quakertown | A 44 | 17,866 | 16 |
| Lehigh Valley | A 56 | 38,535 | 24 |
| Pocono | A 95 | 11,574 | 32 |
| Clarks Summit | A 131 | 6,951 | 24 |
Route Description
Mid-County Expressway Section
The Mid-County Expressway section of Interstate 476 spans 21 miles from its southern terminus at a partial cloverleaf interchange with Interstate 95 in Ridley Township, Delaware County, to the northern terminus at a trumpet interchange with Interstate 276 (the Pennsylvania Turnpike mainline) in Plymouth Meeting, Whitemarsh Township, Montgomery County.[14][15] This freeway, commonly referred to as the Blue Route, functions as a suburban bypass west of Philadelphia, carrying six lanes of divided highway through residential and commercial developments amid rolling terrain with interspersed wooded sections and local waterways such as Darby Creek.[16][17] Unlike the tolled Northeast Extension to the north, this segment operates as a free-access highway maintained by the Pennsylvania Department of Transportation.[7] From the I-95 junction, where traffic merges from the Delaware Expressway, I-476 heads north-northwest through Chester and Ridley Park areas, reaching Exit 1 (milepost 1), a partial interchange with MacDade Boulevard (State Route 3012), providing access to industrial zones and local connectors in Trainer and Marcus Hook.[18] The route then advances into Springfield and Marple townships, crossing Springfield Road and interchanging at Exit 5 (milepost 5) with U.S. Route 1 (Baltimore Pike) via a diamond configuration, serving Media borough and Springfield Township commercial districts.[19][16] Northbound, it curves slightly westward through Upper Darby and Haverford townships, encountering Exit 9 (milepost 9) for Pennsylvania Route 3 (West Chester Pike), a cloverleaf interchange linking to Newtown Square, Broomall, and westward extensions toward West Chester.[19][16] Entering Montgomery County near Ardmore, I-476 shifts northwest, paralleling the Schuylkill River valley, with Exit 13 (milepost 13) connecting to U.S. Route 30 (Lancaster Avenue) in a partial cloverleaf setup, offering entry to Radnor Township, Villanova University, and Saint Davids.[19] The freeway then accesses Exit 16 (milepost 16), a complex directional interchange with Interstate 76 (Schuylkill Expressway), directing traffic eastward toward Center City Philadelphia or westward to Valley Forge National Historical Park and King of Prussia.[19] Approaching the northern end, Exit 18 (milepost 18) provides a partial cloverleaf for Ridge Pike (State Route 3056), split into sub-exits for Conshohocken (18A) and Norristown (18B), facilitating connections to Plymouth Township and the Schuylkill River waterfront.[20][21] The segment concludes at the Mid-County Interchange (Exit 20), where northbound traffic enters the tolled Northeast Extension, while southbound merges from Interstate 276 feed into the free-flow Blue Route.[7][22]Northeast Extension Section
The Northeast Extension of Interstate 476 constitutes the northern segment of the highway, spanning approximately 110 miles from the Plymouth Meeting interchange with Interstate 276 in Montgomery County to its northern terminus at the Clarks Summit toll plaza in Lackawanna County, where it connects to Interstate 81.[23][17] This tolled portion, designated as part of the Pennsylvania Turnpike system, was constructed and opened to traffic in November 1957, providing a direct north-south corridor through eastern Pennsylvania's Appalachian terrain, including forested mountains, valleys, and farmland.[23][14] The extension primarily traverses rural areas, crossing Montgomery, Bucks, Lehigh, Carbon, Luzerne, and Lackawanna counties while serving key population centers such as Quakertown, Allentown, Hazleton, Wilkes-Barre, and Scranton.[19][24] Northbound from the Plymouth Meeting interchange at milepost 20, where the Mid-County Expressway merges into the turnpike alignment, I-476 proceeds through Montgomery County with an initial exit for Pennsylvania Route 63 serving Lansdale at mile 31.[19] The route then enters Bucks County, encountering the Quakertown interchange (Pennsylvania Route 663) at mile 44, facilitating access to local commerce and residential areas amid rolling countryside.[19] Continuing northward, the highway widens to six lanes in sections and reaches the Lehigh Valley interchange at mile 56, a major junction with Interstate 78 and Pennsylvania Route 309 near Allentown, handling significant freight and commuter traffic to the Lehigh Valley's industrial and educational hubs, including Lehigh Valley International Airport.[19][25] Further north, I-476 traverses Lehigh and Carbon counties, passing through the 1.2-mile Lehigh Tunnel at milepost 70 to navigate the Appalachian ridgeline, with an exit for the Mahoning Valley (U.S. Route 209) at mile 74 providing connections to Lehighton and the Slate Belt region's mining heritage sites.[19] The alignment then shifts into Luzerne County, crossing the Pocono Mountains plateau with an interchange at mile 95 for Pennsylvania Route 940 and Interstate 80, serving the recreational areas of the Poconos and access to nearby state parks.[19] Service plazas, such as the Allentown facility between miles 56 and 74, offer refueling and rest areas equipped with dining and maintenance services.[26] In its final segment through Luzerne and Lackawanna counties, the extension handles increased urban proximity, with exits at mile 105 for Pennsylvania Route 115 (Wilkes-Barre), mile 115 for the Wyoming Valley (Pennsylvania Route 315 and partial beltway access to Interstate 81), and mile 122 for Keyser Avenue in Scranton, supporting regional logistics tied to the Wyoming Valley's manufacturing base.[19][25] The route culminates at mile 131 in Clarks Summit, featuring a complex interchange with U.S. Route 6 and Interstate 81, including a prominent bridge structure over the Lackawanna River and a 17-lane toll plaza designed for high-volume processing via E-ZPass and toll-by-plate systems.[7][19] Throughout, speed limits range from 55 to 70 mph, reduced near exits and the Lehigh Tunnel for safety amid the varied topography of valleys, tunnels, and elevated spans.[19]Tolls and Financial Operations
Toll Structure and Collection Methods
Interstate 476 is tolled along its entire length by the Pennsylvania Turnpike Commission (PTC) using an all-electronic tolling (AET) system featuring Open Road Tolling (ORT).[27] Under ORT, implemented on the Northeast Extension by early 2025 with toll plazas removed starting June 2025, vehicles pass under overhead gantries at highway speeds without stopping.[28] [29] Gantries use sensors to detect E-ZPass transponders for automatic deduction or cameras for license plate imaging in the Toll by Plate system.[27] Tolls are calculated based on distance traveled and the number of gantries crossed, with a hybrid structure effective January 5, 2025: a base rate of $0.07 per mile plus $1.09 per gantry for E-ZPass passenger vehicles (Class 2).[30] Toll by Plate rates are higher, applying a markup equivalent to approximately 60% more than E-ZPass, with invoices mailed monthly and additional administrative fees for unpaid or late bills.[30] [31] E-ZPass provides seamless interoperability with 19 states, ensuring deductions from linked accounts.[29] The Mid-County Expressway section (from the Delaware state line to Plymouth Meeting) employs similar gantry-based collection, integrated into the PTC's AET framework since the system's full rollout.[29] Specific toll amounts vary by entry and exit points; for example, a full northbound trip from Swedesford to Clarks Summit costs approximately $25.50 with E-ZPass versus $40+ via Toll by Plate, subject to annual adjustments tied to inflation and infrastructure funding needs.[32] Multi-axle vehicles and commercial classes incur proportionally higher rates per the PTC's class-based schedules.[33]Revenue Generation and Cost Recovery
Revenue for Interstate 476, operated by the Pennsylvania Turnpike Commission as the Northeast Extension, is generated primarily through tolls collected via an all-electronic system using E-ZPass transponders or license plate recognition for Toll-by-Plate users.[27] This open road tolling (ORT) infrastructure, fully implemented on the Northeast Extension by 2022, assesses charges based on miles traveled and vehicle class, with rates adjusted annually to meet financial obligations.[34] For the broader Pennsylvania Turnpike system, which includes I-476, projected toll revenue for fiscal year 2026 stands at $1.8 billion, reflecting traffic growth and rate increases.[35] Cost recovery mechanisms allocate these revenues to operating expenses, capital improvements, and debt service, though a mandated $450 million annual payment to the Pennsylvania Department of Transportation—totaling over $8 billion since inception—diverts funds to state-wide transportation and public transit programs under Acts 44 (2007) and 89 (2013), rather than exclusively to Turnpike maintenance.[36] Approximately $1 billion of system-wide revenue in 2026 will service debt from toll-backed bonds, with long-term obligations driven by these statutory transfers exceeding direct infrastructure costs.[35] The 2026 operating budget of $459.7 million covers maintenance and administration, while a $8 billion 10-year capital plan addresses pavement, bridges, and safety upgrades across the network, including the Northeast Extension.[35] Supplementary revenue streams, such as commercialization of fiber optic infrastructure along the right-of-way through public-private partnerships, provide additional funds but constitute a minor portion compared to tolls.[37] This financing model ensures self-sustaining operations without general tax reliance, though critics argue the diversionary payments impair direct cost recovery and necessitate perpetual toll escalations, with a 4% increase scheduled for January 4, 2026.[38]Facilities and Support Services
Service Plazas and Amenities
The Northeast Extension of Interstate 476, operated as part of the Pennsylvania Turnpike system, includes two service plazas designed to accommodate traveler needs with 24-hour access to fuel, restrooms, and food services via easy-on, easy-off ramps.[39] These facilities, managed by the Pennsylvania Turnpike Commission, are positioned to minimize disruptions to traffic flow while providing essential refueling and respite options along the tolled corridor from Plymouth Meeting northward.[39] The Allentown Service Plaza, located at mile marker 55.9 in Upper Macungie Township, Lehigh County, serves bidirectional traffic with dedicated access ramps for both northbound and southbound directions.[40] Amenities there encompass tourist information centers, ATMs, Pennsylvania Lottery ticket sales, E-ZPass transponder purchases, dog walking areas, travel information boards, compressed air stations for tires, and outdoor seating spaces.[41] Fuel services include multiple gasoline pumps, and dining options feature national chain eateries alongside convenience store items.[39] A dump station for recreational vehicles is also available.[40] Seasonal farmers markets operate at this plaza during warmer months, offering local produce and goods.[42] Further north, the Hickory Run Service Plaza at mile marker 86 near Albrightsville in Carbon County provides similar core services, including restrooms, family restrooms, fuel stations, and a selection of food vendors.[43] This facility supports both travel directions and emphasizes quick access for long-haul drivers heading toward the Pocono Mountains or Scranton area.[39] Like other Turnpike plazas, it maintains round-the-clock operations to align with peak travel demands, such as holiday periods or regional tourism spikes.[39] No service plazas exist along the non-tolled Mid-County Expressway portion of I-476 between Interstate 276 and Plymouth Meeting, where travelers rely on adjacent highway exits for amenities.[39] Both plazas incorporate modern features like Wi-Fi access and E-ZPass compatibility to enhance efficiency, reflecting ongoing investments in traveler infrastructure by the Turnpike Commission.[39]Emergency Response and Maintenance Infrastructure
The Pennsylvania Turnpike's Northeast Extension, comprising the northern portion of Interstate 476 from Plymouth Meeting to Clarks Summit, features a dedicated emergency response system coordinated by the Pennsylvania Turnpike Commission (PTC). Motorists can dial *11 (or 1-800-332-3880) from cellular phones to report incidents, crashes, or request assistance, connecting directly to the PTC's traffic operations center for rapid dispatch.[44][45] The GEICO Safety Patrol operates as first responders, providing traffic control, accident scene management, customer assistance, and minor roadside repairs 24/7 along the route.[46] Authorized towing and emergency road services are contracted through over 20 garages, with response times typically under 45 minutes; charges apply for non-warranty services, such as tire changes or jump-starts, billed directly to drivers.[47] Pennsylvania State Police Troop T exclusively patrols the Turnpike system, including the Northeast Extension, with stations positioned for quick access, such as the Pocono Station serving northern segments.[48][49] Troop T handles enforcement, crash investigations, and security, issuing citations for violations like speeding or wrong-way driving, as seen in incidents on I-476 where they responded to fatal crashes in Lehigh and Washington Townships in 2025.[50][51] Designated emergency response areas, marked by flashing lights and flares, facilitate safe pull-offs during incidents, supported by service plazas like Allentown and Hickory Run for auxiliary aid.[52] The 511PA Connect system enables emergency broadcasting during prolonged closures, alerting drivers via geofenced texts to hazards like stopped traffic.[53] Maintenance infrastructure for the Northeast Extension includes three primary facilities: Lansdale (Milepost A31), Quakertown (Milepost A44), and Lehigh Valley (Milepost A56), each equipped for routine patrols, snow removal, pothole repairs, and vegetation control.[54] These sites support a fleet of over 100 first-responder and safety patrol vehicles system-wide, including specialized units from contractors like McCutcheon Enterprises for hazardous material spills.[55] The PTC maintains 20 facilities across its 550-mile network, with Northeast Extension operations focusing on widening projects, such as the Milepost A38-A44 reconstruction started in April 2022, ensuring structural integrity amid high traffic volumes.[56][57] In contrast, the southern Mid-County Expressway segment of I-476, managed by the Pennsylvania Department of Transportation (PennDOT) from I-95 to Plymouth Meeting, relies on county-level emergency services and PennDOT's district maintenance crews rather than PTC-specific infrastructure, with incidents routed through 911 or PennDOT's traffic management centers.[58] This bifurcation reflects the route's dual governance, prioritizing Turnpike protocols for the tolled northern extent where dedicated resources enhance response efficiency.Exits and Junctions
Comprehensive Exit List
Interstate 476's exits are numbered progressively from its southern terminus at Interstate 95 in Ridley Township, Delaware County, northward to its northern terminus near Clarks Summit in Lackawanna County. The southern Mid-County Expressway portion features closely spaced urban and suburban exits from 1 to 20, while the Northeast Extension includes longer stretches with fewer interchanges, some serving as ticketed entry/exit points under Pennsylvania Turnpike Commission management. All exits provide access in both directions unless noted, with destinations oriented for northbound travel.[19]
| Exit | Destinations | County(ies) |
|---|---|---|
| 1 | MacDade Boulevard, Widener University | Delaware |
| 3 | Media, Swarthmore, Springfield Mall | Delaware |
| 5 | Media Bypass, Lima, Springfield | Delaware |
| 9 | PA 3 – Broomall, Upper Darby | Delaware |
| 13 | US 30 – Villanova, Saint Davids | Delaware/Montgomery |
| 16A | I-76 East – Philadelphia | Montgomery |
| 16B | I-76 West – Valley Forge | Montgomery |
| 18A | Conshohocken, Ridge Pike East | Montgomery |
| 18B | Norristown, Ridge Pike West | Montgomery |
| 19 | Plymouth Meeting, Germantown Pike East | Montgomery |
| 20 | I-276 East (PA Turnpike) – New Jersey; I-276 West – Harrisburg (toll plaza northbound) | Montgomery |
| 31A | PA 63 East – Lansdale | Montgomery |
| 31B | PA 63 – Harleysville, Kulpsville | Montgomery/Bucks |
| 44 | PA 663 – Quakertown, Pottstown | Bucks |
| 56 | I-78, PA 309 – Allentown | Lehigh |
| 74 | US 209 – Lehighton, Stroudsburg | Carbon |
| 87 | PA 903 – Jim Thorpe, Lake Harmony | Carbon |
| 95 | PA 940, I-80 – Hazleton, Mount Pocono | Carbon/Luzerne |
| 105 | PA 115 – Wilkes-Barre, Bear Creek | Luzerne |
| 115 | PA 315 – I-81, Pittston, Scranton | Luzerne |
| 122 | Keyser Avenue – Old Forge, Taylor | Lackawanna |
| 131 | US 6 East – Binghamton, NY (northern terminus) | Lackawanna |