Work is progressing on the New Jersey Department of Transportation’s (NJDOT) $495 million Wittpenn Bridge replacement, the state’s first orthotropic bridge, over the Hackensack River.

“The new bridge offers operational and safety improvements,” says Nick Dogias, Project Manager for NJDOT.

The new structure replaces a bridge built in 1930, which has reached its life expectancy, is structurally deficient, and functionally obsolete, not meeting current standards. For instance, it has two 10-foot lanes in each direction and no shoulders.

The new bridge, about 200 feet to the north of the old structure, will have three 12-foot lanes eastbound and three westbound, inside and outside shoulders, a median barrier separating opposing traffic and a 6-foot sidewalk on the south side.

“We are putting this huge structure in a really congested area,” says Eric Neu, Field Manager for NJDOT. “Decreasing congestion will be a huge improvement.”

About 60,000 vehicles travel on the bridge and SR 7 daily, with a significant amount of truck traffic. Traffic volume is expected to increase. Port Newark and Elizabeth and Newark Liberty International Airport are in the vicinity. It also provides access to the Holland and Lincoln tunnels to New York City. A number of rail facilities and warehouses are located in the area.

“Route 7 is a key component of our Portway corridor,” says Steve Schapiro, Deputy Director of Communications for NJDOT. “The bridge, port, and airport are important for global commerce, not just New Jersey but the entire New York region.”

Both the old and new bridges are lift bridges to accommodate river traffic. The Wittpenn is located in a densely populated industrial area, with no room to build a tall, high stationary bridge. The new structure when closed will be twice as high above the mean high water mark for the deep channel, which can accommodate ocean-going ships at 70 feet, rather than the 35-foot-high current bridge. When open, the clearance will be 135 feet.

“It will require fewer openings, allowing traffic to flow more smoothly,” Schapiro says.

The project required an environmental assessment, primarily for the river work, but there are wetlands in the area. The bridge had been deemed historic. NJDOT will install interpretive signage on the bridge and in other places, including a park in Kearny and New Jersey Transit facilities, explaining the historic corridor.

Jacobs with offices in Clark, New Jersey, designed the new bridge.

This structure will be New Jersey’s first orthotropic bridge. The lightweight deck design features thin steel plates with ribs and transverse floor beams, explains Schapiro, adding that it will make it more efficient to operate the longer lift span. The orthotropic structure also will require less maintenance than a more traditional bridge.

“It was developed in Germany in the 1930s and is similar to U.S. battleship decks,” Schapiro adds. “It’s also like corrugated cardboard.”

The Golden Gate Bridge in San Francisco and the Bronx-Whitestone Bridge in New York have orthotropic decks. About 100 orthotropic bridges exist in the United States, according to a 2012 Federal highway Administration report.

The orthotropic decks were fabricated by Vigor in Portland, Oregon, and Vancouver, Washington, and shipped by barge through the Panama Canal.

The lift span is 324 feet long and 110 feet wide. Three approximately 700-ton deck spans were field welded together. The deck sits on bearings when not raised and lifts by cables.

The contractor used a Donjon Chesapeake 1000 marine crane, with 1,000 tons of lifting capacity to raise the spans. It is the largest marine crane along the East Coast, Neu says. Tug boats moved the crane barge into place. The contractor lifted one span into place per day.

“The crane was one of the larger marine cranes in the country, and the crane was part of the barge,” Schapiro says.

The approach spans, with concrete girders and decks make up the balance of the 3,277-foot-long bridge.

The location of the Wittpenn presented challenges for the construction, with crowded conditions on each end of the bridge, in Kerney and Jersey City. Traffic continued to flow on the old bridge during construction of the new Wittpenn and the approaches. “We have designed new ramps and tie-ins,” Schapiro says.

NJDOT divided the project into five separate contracts, allowing work on different portions to take place simultaneously. “A big challenge was coordinating with all of the contractors,” Neu says.

Contract 1 – awarded to Conti Enterprises of Edison, New Jersey – completed the river piers, large tower and approach spans in the river. Boat traffic needed to pass through the channel during the marine operation. All work took place on barges.

Union Paving and Construction Co. of Mountainside, New Jersey completed Contract 2 for the east approaches. The same contractor completed Contract 3A, the utility relocations and pump station.

CCA Civil of Jersey City, performed Contract 3, the work for the west approach and vertical lift span, with the orthotropic spans. The company completed installing the lift span in September 2020.

George Harms Construction Co. of Howell, New Jersey, received Contract 4 for the completion of the approaches, tie-ins to local roadways, some utility relocation and removal of the old bridge, which will require working off of barges. Additionally, Harms work has included constructing 10 cast-in-place concrete and MSE retaining walls, drilling shafts, placing H-piles, adding permanent sheeting, and making extensive ground improvements including vibro-concrete columns, load transfer mats, and surcharge with wick drains.

The new bridge is expected to open to traffic this spring with work continuing to construct a new ramp to Newark Avenue in Jersey City, as well as complete improvements to the Fish House Road interchange in Kearny. The project is scheduled for completion in early 2023. When it opens, it will increase capacity and enhance safety of motorists.

“You have a lot of commerce that moves through the area, and this bridge is key to that,” Schapiro says. “This bridge will handle the needs today and into the future.”

Photos courtesy of the New Jersey Department of Transportation