Ben Franklin Bridge steel crack spurs inspection

CAMDEN - A contractor is re-inspecting Ben Franklin Bridge steel supports after a crack in a critical roadway support prompted emergency repairs last month, the Delaware River Port Authority revealed Wednesday.

The situation also has prompted the authority to explore the use of drone technology as an added inspection resource.

CEO John Hanson told authority commissioners that HNTB Corp. discovered the crack March 28 as it performed its own inspection work for the design of bridge maintenance painting and other steel repairs at the anchorage on the Philadelphia side of the bridge.

More: Cherry Hill journalist faces child-porn charge

More: 10 updates on biking in South Jersey: Laws, lanes and trails

The contractor found "significant deterioration" of one of two steel, V-shaped wind braces under the roadway that are designed to provide stability and prevent excessive sideways sway, especially in strong winds, according to Hanson.

The suspension bridge is designed to have some flexibility of movement.

"A HNTB employee was inspecting the lateral brace when a PATCO Hi-Speedline train passed overhead and he saw that there was too much movement," Hanson explained.



"Due to the location, knowledge of the bridge and magnitude of the repairs required, we enlisted the assistance of HNTB and Cornell & Co. Inc. of West Deptford — already on DRPA property performing steel repairs on the Walt Whitman Bridge — to make these repairs," he said.

As soon as the problem was discovered, PATCO trains using the bridge were ordered to reduce their speed from 30 mph to 15 mph until the repairs were completed.

"As an abundance of caution, we also placed restrictions on roadway crossings by overweight vehicles that require a truck permit," Hanson said.

The last full bridge inspection was in 2016.

"The 2016 inspection found only minor deterioration of that same support," Hanson recalled.

There are two V-shaped lateral supports under the roadway at both the Philadelphia and Camden anchorages, and a subsequent inspection of the other three has revealed no problems so far, DRPA Chief Engineer Michael Venuto said.

The repair was completed April 5 and PATCO trains resumed their normal bridge crossing speed.

Hanson said he invoked his emergency powers to authorize a $150,000 payment to Cornell for parts, delivery and installation. He expects additional charges for HNTB's engineering to determine the type of repair — replacement of part of the support beam and a bolted connection.

"I know we have a robust inspection program," board Chairman Ryan Boyer said at the commissioners meeting Wednesday, "but can we consider using drone technology for routine inspections?"

Although Venuto said a drone would have been unable to detect this particular steel support problem because of its location, he agreed "it's time to incorporate that technology into the inspection program."

Carol Comegno: @carolcomegno; 856-486-2473; ccomegno@gannettnj.com

Also in South Jersey