At a final cost of more than $110 million, Section A09 of the Lewistown Narrows is one of PennDOT’s largest and most complex construction projects.  This section was the second largest construction project bid ever awarded by PennDOT, when the $104.36 million bid was awarded in 2004.  (The largest single construction project bid prior to A09 was Route 202, Section 404, in Montgomery County at $104.86 million.)

A09 is the third and final section of the nearly 10-mile long Route 22/322 Narrows reconstruction project in Central Pennsylvania's Mifflin and Juniata counties.  

What it took to build this section:

• 46 miles of 7-inch diameter slope stability micropiles

• 15 miles of steel beam bearing piles (H-piles)

• about 25 lane miles or 100,000 cubic yards of roadway concrete/slipforming

• 18.2 miles of barrier and parapet concrete/slipforming  

• 9 reinforced concrete retaining walls cast in place totaling 1.7 miles

• almost 3 miles of MSE (mechanically stabilized earth) walls: one at 12,100 feet long is the 2^nd longest in the world

• 400,000 tons of backfill

• 8.5 miles of drainage pipe

• 50,000 tons of bituminous paving

• 170,000 cubic yards of concrete

• 2 million cubic yards of excavation, including 1 million cubic yards of rock

Begun in 2004, the four new lanes of Section A09 were open to traffic by December 14, 2007, far ahead of the original Fall 2008 schedule.  Public amenities are to be completed in Spring 2008.  At 6.65 miles in length, this section was one of the more complex projects to design and build because of the need to position the four-lane highway between the talus rock slope of the Shade Mountain and the Juanita River.  For more than three decades, engineers considered ways to efficiently build a wider, modern highway while maintaining slope stability even after construction. 

Some 40,000 core drillings, seismic refraction, and ground penetrating radar were used to analyze potential stability issues and evaluate construction alternatives.   Seismic monitoring continued during construction. 

The design 

The design minimized excavation along the talus rock slope.  All of the project design elements tie together to help ensure "global" stability of the site. Part of the highway is bifurcated, with the two westbound lanes elevated above the eastbound (riverside) lanes for about three miles.

There are more than four miles of retaining walls, including two mechanically stabilized earth (MSE) walls, one of which is two miles in length and is the longest MSE wall in the United States and the second largest in the world.  There are nine reinforced concrete retaining walls along the riverside totaling 8,280 feet.

There are also more than 46 miles of remediation pipe piles – piles embedded into the bedrock and filled with cement grout to add slope stability and also to counteract the weight of the completed highway.  These piles are installed between the new highway lane areas and along the river's edge. 

Construction included two bridges, 55 feet and 290 feet long, both over Macedonia Run, and three box culverts totaling 486 feet.  There are 51,000 feet, or 15 miles, of H-piles in project walls and bridge foundations. 

The completed highway has two 12-foot-wide lanes in each direction with 10-foot outside concrete shoulders. Inside shoulders vary from four to nine feet.  The completed median area includes concrete glare screen barrier, where the median is narrow, and in other areas there is earth median, which varies from 45- to 84-feet-wide.

Special traffic provisions

One lane of traffic in each direction was maintained throughout the project using combinations of the two-lane, existing roadway; temporarily widened portions of the highway; temporary crossovers and roads; and the newly-built lanes as the project progressed. 

Frequent traffic alerts were issued and also posted on this site.  (See Narrows traffic alerts page.)  

Traffic on the roadway.

Traffic updates are also posted on message boards as well as highway advisory radio (16.40 AM).

Environmental Considerations

Because of wetland impacts, a wetlands mitigation area was created in Lack Township, Juniata County. (See Section A11.)  There also was compensatory mitigation in Oliver Township, Mifflin County, done under Section A10.

There are bass and trout in the streams and river.

Work at Horning Run, Macedonia Run, Roaring Run and two tributaries was timed to minimize impacts on both wild and stocked trout.   

Fish baffles were placed in box culverts to provide habitat.

A causeway was built along the river as a platform to construct a concrete retaining wall along the river for the eastbound lanes.  Special provisions, such as working downstream to upstream to keep the water clearer, helped minimize impacts to fish and turtles.  

Other measures to protect fish habitat included putting native rock in place; dropping and anchoring some trees in the river; and placing fish baffles in the box culverts.  The causeway was left in place to provide ongoing habitat.

During causeway construction, a herpetologist or reptile expert was on site to catch or chase away any turtles.  There are several turtle species in the area, including the Wood Turtle.  That turtle is not considered endangered in Pennsylvania, but is endangered in some other states.

Trees and vegetation were not disturbed if it wasn’t necessary. The endangered Wild Senna wildflower was protected with fencing during construction.

Encountering snakes, such as Timber Rattlesnakes and Northern Copperheads, is a possibility when constructing a highway in this setting.  How snakes are protected under the Pennsylvania Fish & Boat Code was included in special crew training, as was snake identification and first aid procedures.  Some of the crews wore snake boots or chaps for additional protection, and Lewistown Hospital stocked anti-venom in case someone is bitten.  

Recreation, History & Education

The Pennsylvania Canal and the Canal House, built in 1860, are special features in the area.   As much of the canal as possible is being preserved.  The Canal House structure was saved for future conversion to a museum/visitor center.  

As one of the last construction phases, part of the canal towpath will become a 1½ mile-long trail along the Juniata River between the new Canal Park and a new fishing boat access area.  When completed in Spring 2008, it will feature an overlook above the canal lock. 

	The Canal house, built in 1860 Photo by John Strawser

The new Macedonia Run Canal Park will have a picnic area, parking, and information kiosks.  Along the river will be a parking area, a boat launch, information kiosks and an access area for people who are physically challenged.

The A09 project team

• PennDOT
• Maguire Group Inc., Pittsburgh – construction management
• EADS Group, Inc. Altoona – principal designer
• Erdman Anthony Associates, Inc. and GTS Technologies Inc. – design consulting
• Walsh Construction, Pittsburgh – prime contractor
• T.W. Consultants, Inc., Pittsburgh  –  inspection