PennDOT's Squirrel Hill Tunnel Reaches New Heights

Over 65 years ago, crews broke ground on the single largest investment in PennDOT history. At the time, PennDot invested 18 million dollars into the eastern gateway to the City of Pittsburgh. The gateway became known as the Squirrel Hill Tunnel. The Squirrel Hill Tunnel is a twin bore, or twopassageway tunnel. Each bore serves as a two lane directional path in and out of the city. The 4,225 feet long, 28-foot wide, 13-foot 6-inch tall tunnel serves approximately 106,000 vehicles every day.

Due to rising fuel prices, the need to increase the size of shipments, and the advancements in technology, tractor trailers have increased in height. Because of the changing dynamic in the transportation industry, there have been hundreds of “ceiling strikes” over the past few decades. The “ceiling strikes” cause extreme traffic jams that can effect entire workdays. In order to correct this, PennDOT designed a plan to remove the ceiling in this tunnel.

For several months now, different trades have been working atop the tunnel ceiling. They are relocating all of the mechanical and electrical equipment to the tunnel roof. All of this preparation work is taking place in order to keep the tunnel operational during the ceiling removal phase.

Several weeks prior to mobilization, our fabricators, mechanics, engineers, and field managers all collaborated to design and fabricate lighting and roadway protection systems. These systems must be mobile, strong and functional. Their primary purpose is to protect the tunnel lighting, ceramic tile on the walls, concrete curbs, the roadway pavement, and, most importantly, the construction team and general public.

The first type of protection system is for the bulk ceiling removal. When processing the concrete from the ceiling, this system guides all of the bulk concrete debris down a steel plate and into a 30-yard roll-off dumpster. To protect everything, the protection apparatus for bulk removal must work in a pair, each one straddling the wall, lights, and curbs on either side of the tunnel.

The second type of protection system for the handwork has the same primary function as the first system. However, the second system is for use during single lane closures at night, during the week. This system protects all of the physical properties of the tunnel, as well as motorists. While standing atop of this protection system, laborers use jackhammers to remove the remaining portion of the ceiling, which is unreachable by heavy equipment.

Along with the ceiling removal, there are several drains that need removed. Due to the asbestos content of these drains, we enlisted the help of our sister company, Precision Environmental Co. Precision Environmental Co. has 25 years of experience in full-service asbestos abatement, environmental remediation, and selective demolition. Their experience and training assured us that all of the asbestos would be contained and disposed of safely and properly.

Over the next couple of years, 25,000 hours of running jackhammers, equipment, and sawing concrete will be completed. All of these hours will contribute to the removal of approximately 7,500 cubic yards of concrete ceiling. A project of this magnitude, coordination, and complexity requires many different resources. Our heavy equipment shop, design and engineering department, support team, and operations department give us the experience and the resources to take on, adapt, and complete such a unique project. This job fully demonstrates the diverse capabilities that Independence Excavating Inc. and DiGeronimo Companies can offer.

We would like to thank the Independence Excavating team who are working tireless night and weekend hours to keep this project moving forward. We would also like to thank PennDOT, Michael Baker Jr. Inc., Walsh Construction Company, McClymonds Trucking, Precision ProCut, and Precision Environmental Co. for their partnerships. This outstanding group of agencies, contractors, and engineers will contribute to the success of this historic project for the City of Pittsburgh and its 106,000 motorists passing through the tunnels every day.