The Broad Street Quay Wall Reconstruction Project revitalized a 734-foot stretch of Broad Street in Philadelphia, enhancing safety and accessibility for the 150 businesses and 15,000 employees at the historic Navy Yard. The scenic waterfront area, with views of decommissioned naval ships, faced challenges due to a deteriorating relieving platform that had made the waterfront inaccessible.

The original Quay Wall was constructed over 120 years ago to form the eastern edge of the Navy Reserve basin. The timber low deck relieving structure had passed its useful lifespan. The deteriorating structure underwent a transformation costing $20 million. This collaborative effort involved PennDOT, the U.S. Economic Development Administration, the City of Philadelphia, and the Philadelphia Industrial Development Corporation (PIDC). The project introduced four vehicle lanes, a two-way raised bike lane, and a new pedestrian plaza. The project's key features included installing a new bulkhead to support the sidewalk and roadway, advanced streetscaping, and updated drainage infrastructure. The 734-foot section of Broad Street was realigned 16 feet inland to match the northern and southern legs of Broad Street through this area. This section was historically offset from the rest of the straight roadway due to the Reserve Basin. The realignment created a straighter, safer corridor for vehicles, cyclists, and pedestrians. Additional improvements included modernized water and sanitary utilities, enhancing the area’s safety, accessibility, and aesthetic appeal while preserving its historic charm. Overall, the project transformed the Quay Wall into a vibrant and inviting space for the community.

Project Details:

Urban was the lead engineering firm for the project, responsible for delivering bid-ready drawings and specifications, construction cost estimates, and schedules for each design development phase, from preliminary to final. The firm's services included replacing the deteriorated timber pile supported low deck quay wall, new utilities, a realigned street, new sidewalks, and a new designated elevated bike lane. Urban also contributed to enhancing the pedestrian experience by designing new landscaping and streetscaping features.

The new steel sheetpile wall is recessed approximately 6 feet beneath the sidewalk, completely hidden from view as the public travels along the roadway. The pile-supported deadman, responsible for anchoring the tie-rods that stabilize the top of the wall, is positioned 60 feet behind the sheetpile wall beneath the northbound lanes of the roadway. Additionally, the sidewalk is supported by steel pipe piles under the new railing at the edge of the project.

To ensure the longevity of the new structure, a bulkhead, deadman, and piles were incorporated to support the sidewalk and roadway. The elements were constructed using durable materials to withstand future environmental events such as flooding, and storm surges associated with climate change. In addition to structural enhancements, the project features new streetscaping, upgraded drainage systems, and an elevated bike lane, improving public safety and accessibility while enhancing the area's resilience.

Challenges:

Like many areas in Philadelphia, the Navy Yard has a rich history. The site was once known as League Island, an island in the Delaware River during the mid-1800s. At that time, a water channel flowed behind the Quay Wall, and a bridge carried Broad Street over the channel to access League Island. Remarkably, an old sketch of this bridge was uncovered during the project’s initial studies.

By the late 1800s, the channel was filled with dredged materials, and the original Quay Wall was built along the eastern edge of the Naval Reserve Basin. However, there were no records of what happened to the bridge.

During construction, a massive timber structure was discovered beneath the surface near the new concrete deadman. Careful excavation revealed that this structure matched the old sketch of the bridge, confirming that the original bridge had been buried and paved over in the late 1800s when the new roadway was built. 

While the buried bridge didn’t interfere with the placement of tie rods, driving the battered piles for the deadman became a challenge. The piles had to be driven toward the bridge, but its timber construction blocked their path. The project team overcame this obstacle by using conical tips on the piles, allowing them to penetrate the timber elements and be installed to their designed capacity.

Benefits:

The project improved accessibility, safety, and sustainability in a previously underused area of the Navy Yard, turning it into a more welcoming and functional waterfront space. By addressing outdated infrastructure and adding features like a pedestrian plaza and a raised bike lane, the changes encourage more public use and better connect the Navy Yard with the city. Economically, the $19 million investment created over 13,000 jobs and helped attract businesses, supporting local economic growth. Environmentally, the project included sustainable features like stormwater management and better transportation options, encouraging more eco-friendly travel. Finished ahead of schedule, the project achieved its goals while also considering long-term sustainability and resilience.