Case Study

TrapBag Cofferdam Supports Riverbank Remediation in Scranton, Pennsylvania

Standard TrapBag® TBRCD120 Liftable Cofferdam Bags were used to construct a 12-foot-tall temporary cofferdam along the Lackawanna River as part of an environmental remediation project in Scranton, Pennsylvania.

Designed by Stantec Consulting Services for UGI Utilities, the cofferdam isolated the active work area, allowing in-situ soil stabilization to be performed while helping protect the adjacent river.

Project Specifications

Product used: Standard TrapBag® TBRCD120 Liftable Cofferdam Bags

Installation configurations: Multiple stacked courses over a permanent gabion foundation

Material: TrapBag Cofferdam Bags; specific fabric composition is not provided

Fill material: Dense graded aggregate

Reinforcement: Temporary steel protection plates

Liner: Protective liner secured with sandbags

Barrier height: 12 feet

Application: Environmental remediation and temporary water control

Waterway: Lackawanna River

Project owner: UGI Utilities

Engineer: Stantec Consulting Services

Initial Solution

The project required a temporary water-control barrier that could accommodate changing streambed elevations and support construction immediately adjacent to the Lackawanna River. The installed system included:

  • Standard TBRCD120 Liftable Cofferdam Bags
  • A permanent gabion base
  • Dense graded aggregate fill
  • A protective liner
  • Temporary steel protection plates
  • Sandbags securing the liner
  • Temporary erosion and sediment control measures

The modular design allowed the cofferdam to adapt to existing site conditions while creating a stable, protected work area.

Project Expansions and Reinforcements

The TBRCD120 Cofferdam Bags were installed over a permanent gabion foundation and stacked in multiple courses to achieve a total barrier height of 12 feet.

The stacked TrapBag system worked together with a protective liner, temporary steel protection plates and sandbags securing the liner. These components helped isolate the work area and provided additional protection for the temporary barrier during construction.

No later expansion of the original installation is documented.

Performance

The TrapBag Cofferdam System successfully created a protected construction zone immediately adjacent to the Lackawanna River. It supported the environmental remediation effort, adapted to varying streambed conditions and integrated with the project’s permanent gabion structure.

The completed system provided temporary water control while in-situ soil stabilization was performed and remained removable after the work was completed. No catastrophic flood, storm or other extreme-event performance is documented for this project.

Key Outcomes

  • Created a protected construction zone for in-situ soil stabilization immediately adjacent to the Lackawanna River.
  • Adapted to varying streambed elevations while integrating with the project’s permanent gabion structure.
  • Provided a removable temporary water-control solution that supported remediation without becoming a permanent barrier.

Conclusion

The Scranton remediation project demonstrates how the TrapBag® Cofferdam System can be configured for temporary water control in challenging riverbank environments. By stacking standard TBRCD120 Liftable Cofferdam Bags over a gabion foundation, the project team created a 12-foot barrier capable of adapting to existing streambed conditions.

Installation Highlights

  • Lackawanna River installation in Scranton, Pennsylvania
  • 12-foot-tall temporary cofferdam
  • Standard TBRCD120 Liftable Cofferdam Bags
  • Multiple stacked courses
  • Installed over a permanent gabion foundation
  • Filled with dense graded aggregate
  • Adapted to varying streambed elevations
  • Protective liner secured with sandbags
  • Temporary steel protection plates
  • Removable after remediation was completed