File photo: Route 42 in New Jersey. (Tom MacDonald/WHYY)
An investigation has revealed that the retaining wall, built as part of the I-295 “Direct Connect” project in Camden County, collapsed due to multiple factors, including the wrong type of sand used to support the wall, which was already standing on land previously identified as showing signs of instability.
Also, the concrete columns were not adequate to withstand loads from the elevated roadway or the wall to provide a “suitable safe” foundation. Heavy rain showers the day before the wall collapsed in March 2021 didn’t help either. The roadway was not open to traffic.
The New Jersey Department of Transportation hired engineering firm Hardesty & Hanover to conduct a forensic investigation into the wall collapse. Transportation Commissioner Diane Gutierrez-Scaccetti announced the hiring of an independent engineer, nearly two weeks after the collapse. The 7,000 page report was completed in January, but media outlets — including WHYY News — received it this week in 11 parts after filing an Open Public Records Act request.
Construction on the wall — referred to in the report as “Wall 22” — began in 2018 as part of the long-term road project designed to allow I-295 to flow freely without using ramps connected to the Route 42 freeway.
The project was plagued with challenges even before construction began.
Issues began to appear as early as 2016 when a split or “fissure” in the land slope where the wall was ultimately built appeared. In February 2019, construction was paused for several weeks when several of the panels shifted. About two weeks before the wall collapsed, the first cracks in the pavement above Wall 22 were noticed.
Prior to the completion of the report, Commissioner Gutierrez-Scaccetti said last December that the area where the collapse occurred was “a fairly wet area” already. It was not clear at the time who would pay for the new wall. However, the collapse has pushed the expected completion date of the “Direct Connect” project to 2028.
In a joint statement, U.S. Rep. Donald Norcross and Assemblyman Bill Moen said issues at the site can be traced back almost a decade, and vowed to make sure similar problems don’t happen.
“We want to be clear: this is unacceptable,” they wrote. “We will work to ensure that an event like this never occurs again.”
Moen introduced a bill in the Legislature in May that would require a geotechnical engineer to provide recommendations concerning the type and frequency of tests needed for transportation projects. The recommendations would then be included in construction contracts.
It would also require a groundwater test within six months before construction begins on projects that would need it, and ongoing testing should conditions warrant.