I-95 Scotch Road Interchange

When Merrill Lynch proposed to relocate their corporate headquarters to Ewing, NJ, Arora and Associates was up to the challenge to meet the demanding schedule for a major I-95 Interchange reconstruction dictated by both Merrill Lynch and New Jersey Department of Transportation.

Arora went to work immediately to identify roadway design issues, projected traffic volumes, utility, right-of-way, environmental, community and traffic issues. In a remarkably short time frame, Arora proposed conversion of this diamond interchange to a full cloverleaf. Arora also recommended the addition of two collector-distributor (CD) roadways on Route I-95, superelevating over one mile of interstate roadway to eliminate substandard geometry and replacing the functionally obsolete bridge.

Arora's structural engineers found innovative solutions to reduce the project costs. Among them was NJDOT's first use of high performance weathering steel (HPS70W). The use of this material reduced costs by eliminating an entire girder line and provided greater flexibility in staging the replacement of the bridge. Construction time and costs were shortened by the design of prefabricated wall systems. Integral abutments eliminated deck joints and simplified construction details. Instrumentation of the high performance steel girders and the abutments were incorporated into the contract to assist NJDOT in evaluating the performance of this new material and preparing future design standards. During design, Arora used the bridge as a test case to evaluate the cost impacts of implementing the draft NCHRP 12-49 seismic specifications for NJDOT.

Other challeges that Arora handled were wetlands mitigation and numerous utilities that required relocation or protection including multiple gas pipelines and a sewer pump station. Maintenance and protection of traffic during construction was a concern due to the high volume of commuter traffic through the interchange. Arora provided complete MPT plans and developed contract durations and incentives for lane outages and detours.

The project was named Project of the Year by the Professional Engineer's Society of Mercer County and Outstanding Enginering Acheivement by the New Jersey Society of Professional Engineers.

The project was completed on schedule at a cost of $24.3 million.