I-95 Section CP2 Cottman Avenue Interchange Improvement 

The $212 million reconstruction of I-95, Section CP2— a 1.4-mile-long elevated highway between the Academy Road and Bridge Street interchanges in Philadelphia— is the Pennsylvania Department of Transportation (PennDOT)’s second largest infrastructure investment, ever. Urban is providing construction inspection services for the complex, six-phase project. Work includes widening I-95 to four lanes with the construction of 16 retaining walls; reconstructing seven bridges; reconfiguring the Cottman Avenue interchange with the construction of a new southbound on-ramp; widening and improving a southbound off-ramp; and upgrading the intelligent transportation systems network with 13 Arterial Dynamic Message Sign (ADMS) structures. Other work includes reconstruction of several blocks of New State Road, extension of Princeton Avenue under I-95, and replacement of several water mains and a large reinforced concrete sewer culvert.

Urban’s inspection team reviews submissions for compliance with standards, monitors construction schedules, audits costs, and verifies that work complies with contract documents. We coordinated with local businesses to provide alternate truck routes for use during replacement of 800 feet of Conrail track and three grade crossings. We also meet weekly with various utility companies to help keep the project on schedule and within budget.

Unique to this project is the relocation of a large 84-inch diameter water main and 10’x10’ sewer, which is required to construct a new southbound on-ramp.  This is the first relocation of a water main of this size, composition, and importance to be completed in America. The water main impacted by the work supplies half of Philadelphia’s drinking water. To maintain water service, a bypass main was installed. Two pressurized water taps will tie in the relocated main to an adjacent main, which will stay in service during the relocation. This involves use of a large cutter within a pressurized chamber. Once the new main is installed and the wet taps are completed, two additional line stops will be installed on the existing water main to divert the flow into the newly relocated water main. Urban meets weekly with the Philadelphia Water Department and specialty contractors completing this complex work. We help study the feasibility of the relocation, review plans, and address problems that arise, such as difficulties dislodging the cutter from the pipe.

Other critical underground work includes construction of seven 3-foot to 7-foot diameter stormwater drains on a pile-supported foundations. These drains snake under residential neighborhoods and carry stormwater from I-95 to the Delaware River.

Completion of Section CP2 is the final phase in PennDOT’s Cottman Avenue Interchange Improvement Project. This rebuilt and wider section of I-95 will provide better, safer access to Philadelphia neighborhoods and businesses and enhance travel along a major east coast highway. 

 ​Highlights

• High-profile massive interstate reconstruction in urban environment
• Relocation of large water main—the first of its kind to be completed in America
• Close coordination with public and private utilities
• One of PennDOT’s largest infrastructure investments