Interstate 99

Interstate 99
Map of southwestern Pennsylvania and vicinity with I-99 highlighted in red
Route information
Maintained by PennDOT
Length	85.0 mi (136.8 km)
Existed	1998–present
NHS	Entire route
Major junctions
South end	I-70 / I-76 / Penna Turnpike / US 220 near Bedford
Major intersections	PA 56 near Cessna US 22 near Altoona US 322 near State College PA 26 near Pleasant Gap PA 64 near Pleasant Gap
North end	I-80 near Bellefonte
Location
Country	United States
State	Pennsylvania
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Future Pennsylvania State Route System Interstate US State Scenic Legislative
← PA 98 → PA 99

Interstate 99 (I-99) is an intrastate Interstate Highway entirely within central Pennsylvania. The current southern terminus is at exit 146 of the Pennsylvania Turnpike (I-70/76) north of Bedford, where the road continues south as U.S. Route 220. The northern terminus is currently at Interstate 80 near Bellefonte, Pennsylvania. The interstate passes through Altoona and State College, home to Pennsylvania State University. I-99 closely follows the path of US 220.

Unlike most Interstate numbers, which were assigned by AASHTO to fit into a grid, I-99's number was written into Section 332 of the National Highway Designation Act of 1995 by Bud Shuster, then-chair of the U.S. House Committee on Transportation and Infrastructure, the bill's sponsor, and the representative of the district through which the highway runs. Interstate 99 violates the AASHTO numbering convention associated with Interstate Highways, since it lies east of Interstate 79 but west of Interstate 81.

When construction on I-99 is completed, the southern terminus of the route will be at an interchange with Interstate 68 in Cumberland, Maryland. The northern terminus will be at an interchange with Interstate 86 in Corning, New York.

Route description

While the current road runs from Bedford to Bellefonte, Pennsylvania, future plans have this road starting from the Pennsylvania–Maryland border mostly along US 220 and then continuing northward along U.S. Route 15 towards the New York state line.

The names given to this road include the Bud Shuster Highway and the Appalachian Thruway. The latter name continues north with US 220 and US 15.

Bedford to Altoona

Interstate 99 currently begins as a continuation of the two-lane portion of US 220 from Maryland near the Pennsylvania Turnpike (I-76). The interchange with the turnpike requires drivers to get onto Old US 220 near Bedford to enter the Pennsylvania Turnpike.

Altoona to I-80

From Altoona, the highway has a large intersection with U.S. Route 22 in Hollidaysburg. This interchange allows travellers to head west towards Ebensburg, Johnstown, and Pittsburgh. Pennsylvania Route 764 intersects further at Bellwood.

A map of the Mount Nittany Interchange.

Northward towards Tyrone, Interstate 99 runs along one of the older sections of the highways when US 220 was first converted to a limited access highway.

In Tyrone itself, Interstate 99 is a short elevated expressway at Pennsylvania Route 453.

Until the end of 2007, the highway ended north of Tyrone at the village of Bald Eagle, where traffic was diverted to US 220. On December 22, 2007, after several long construction delays, the section from Bald Eagle to Port Matilda was opened to traffic. The remaining section to just short of Interstate 80 near Bellefonte (via the Mount Nittany Expressway) was opened to traffic the week of November 24, 2008.

History

Interstate 99 excavation in 2002, looking south from Julian toward Port Matilda on Bald Eagle Mountain, where acidic rock was exposed. U.S. Route 322/220 (Skytop Mountain Road), runs below the I-99 alignment. Eagle Field private airport is at the upper left

Corridor O of the Appalachian Development Highway System was assigned in 1965, running from Cumberland, Maryland (Corridor E, now Interstate 68) to Bellefonte (Interstate 80) along US 220. The portion in Pennsylvania, from Bedford north to Bald Eagle, was upgraded to a freeway in stages from 1970 to 1995.

As the interchange with the Pennsylvania Turnpike near Bedford was built long before the new freeway opened, there is no direct freeway-to-freeway access between the Turnpike (I-70/76) and I-99. Traffic must use U.S. Route 220 Business, the old alignment of US 220 before the freeway.

In 1991, the Intermodal Surface Transportation Efficiency Act (ISTEA) was signed into law. It included a number of High Priority Corridors, one of which - Corridor 9 - ran along US 220 from Bedford to Williamsport, Pennsylvania, and then north on U.S. Route 15 to Corning, New York.

The National Highway Designation Act of 1995 amended ISTEA; among these amendments were that "the portion of the route referred to in subsection (c)(9) [Corridor 9] is designated as Interstate Route I-99." This was the first Interstate number to be written into law rather than assigned by the American Association of State Highway and Transportation Officials (AASHTO). The number was specified by Representative Bud Shuster, who said that the standard spur numbering was not "catchy"; instead, I-99 is named after a street car, No. 99, that took people from Shuster's hometown of Glassport to McKeesport. (Interstate 73 and the extension of Interstate 74 had been defined in 1991 by ISTEA as the "I-73/74 north–south Corridor", but not officially added to the Interstate Highway System or assigned those numbers.)

On November 6, 1998, AASHTO approved the I-99 designation from Bedford to Bald Eagle. Since then, the connection through the Nittany Valley between the existing State College bypass on U.S. Route 322 and Interstate 80 has been built (the northernmost piece was widened from a two-lane freeway in 1997). On its completion in 2002, US 220 was rerouted via US 322 and the new road, and the old US 220 north of US 322 was designated U.S. Route 220 Alternate.

Future

Future I-99 Corridor sign on US 15 South, north of Williamsport, Pennsylvania.

S. 719, sponsored by Paul Sarbanes of Maryland, would have extended Corridor O south to Corridor H in West Virginia.

As defined in Federal law, I-99 is to continue north to Corning, New York. Signs have been placed along the present US 220 and US 15, much of which are built to Interstate Highway standards, marking the route as the "Future I-99 Corridor".

Maryland

The full route of I-99 is part of Corridor O of the Appalachian Development Highway System, which runs along US 220 from Interstate 68 near Cumberland, Maryland north onto I-99 near Bedford, Pennsylvania.

Pennsylvania

Interstate 99 is planned to start from the Maryland border to be a continuation to the existing routing that starts in Bedford.

From Bellefonte to Williamsport, plans are to have this road continue along US 220.

From Williamsport to Corning, New York, plans are to have this road continue along U.S. Route 15 to the state line.

New York

In the state of New York, this road is slated to continue north from Pennsylvania along U.S. Route 15 to Interstate 86/NY 17 near Corning, where the freeway would then provide a link to Rochester via I-390. New reference markers installed on now US 15 indicate this stretch as the I-99 corridor with the "99I" on the markers.

Exit list

County	Location	Mile	Exit	Destinations	Notes
Bedford	Bedford Township	0.00	1	I-70 / I-76 / Penna Turnpike – Pittsburgh, Harrisburg
		2.93	3	PA 56 (US 220 Bus. south) – Johnstown, Cessna
	East St. Clair Township	6.65	7	PA 869 – St. Clairsville, Osterburg
	King Township	10.13	10	Blue Knob State Park
Blair	Greenfield Township	14.92	15	Claysburg, King (US 220 Bus. north)
	Freedom Township	22.88	23	PA 36 / PA 164 to US 22 east – Roaring Spring, Portage, Hollidaysburg
	Allegheny Township	28.12	28	US 22 – Ebensburg, Hollidaysburg
	Logan Township	30.60	31	Plank Road (US 220 Bus.)
		31.88	32	To PA 36 (Frankstown Road)
		33.24	33	17th Street
	Antis Township	38.62	39	PA 764 south – Pinecroft
		41.30	41	PA 865 north – Bellwood
		45.41	45	Tipton, Grazierville
	Tyrone	47.89	48	PA 453 – Tyrone
	Snyder Township	51.84	52	PA 350 (US 220 Bus. south) – Bald Eagle
Centre	Worth Township		61	Port Matilda (US 220 Alt. north)
			62	US 322 west – Philipsburg	South end of US 322 overlap; southbound exit and northbound entrance; northbound exit is via exit 61
	Patton Township		68	Gray's Woods, Waddle
			69	US 322 Bus. east (Atherton Street)	Northbound exit and southbound entrance
			69	Valley Vista Drive – Park Forest	Southbound exit and northbound entrance
			71	Toftrees, Woodycrest
	College Township		73	US 322 east – State College, Lewistown	North end of US 322 overlap
			74	Innovation Park, Penn State University	Northbound exit is part of exit 73
	Benner Township		76	Shiloh Road
			78	PA 150 – Bellefonte	Signed as exits 78A (south) and 78B (north)
	Spring Township		80	Harrison Road	Northbound exit and southbound entrance
			81	PA 26 south to PA 64 – Pleasant Gap	South end of PA 26 overlap
			83	PA 550 – Bellefonte, Zion
		North end of freeway
				I-80 / US 220 north (US 220 Alt. south) – Williamsport, Dubois

External links

• Interstate 99 at
• News on the I-99 acid-rock cleanup from CentreDaily.com

• Pennsylvania Highways: Interstate 99