A probe continues by construction engineer Hardesty and Hanover LLC into what caused the late March collapse of a retaining wall that is part of one of New Jersey's largest roadbuilding projects—the already late-running effort called Direct Connection, which aims to untangle the convoluted interchange of north-south I-295 and east-west Route 42 in Camden County.

NJ Dept. of Transportation officials, who also are investigating the collapse of the 35-ft-high, 300-ft-long wall section, have yet to reveal any potential causes or estimate schedule impacts for the interchange reconstruction, already pushed back to 2028, or cite repair costs added to the project, now budgeted at more than $900 million overall.

DOT spokesman Steve Schapiro says the investigation is not completed, "with the goal of determining the cause as soon as possible." He adds that it is "too soon to know how the collapse will affect the project schedule."

Schapiro says there were no injuries in the collapse and that no other similar project ramps are being investigated for possible collapse danger.

State officials have said Direct Connection already is four years off a previous 2024 completion estimate, noting that when a collapse cause is determined, a repair will be designed.

Demolition of the collapsed wall and site excavation began in April and will continue in stages, but DOT officials won’t know how soon the work will be completed until experts determine if the soil is secure.

The contract for the portion of the project that collapsed had been awarded to contractor South State Inc., Bridgeton, N.J. The firm did not return a request for comment.

An estimated 240,000 vehicles travel through the affected area daily, according to the state DOT.