NJDOT Water Force Main Support Project in Princeton, NJ

The challenge

This project required construction directly over a critical utility with zero tolerance for movement, settlement, or vibration-induced damage. The work was performed under strict NJDOT oversight, with the local water authority present throughout drilling operations to ensure the integrity of the force main. In addition, a third-party testing agency conducted vibration monitoring adjacent to the pile installation, and survey crews measured the pipe elevations before and after construction to verify that no displacement occurred. Coordinating these requirements within a constrained right-of-way created a highly controlled and technically demanding construction environment.

The Claycor solution

Fuller Pile provided a “no-vibration” deep foundation system capable of transferring roadway loads away from the force main while maintaining constructability within tight site constraints. The FP450 piles were strategically installed to flank the pipeline, creating a structural system that effectively isolated the utility from new surface loads. A key advantage of the Fuller Pile system on this project was its inherent flexibility, which allowed the delegated design team to quickly and economically accommodate a late-stage load-change request from the project engineer just before installation, without impacting the schedule or requiring redesign of the overall system.

Implementation & construction

Construction was executed with a high level of coordination among NJDOT, the local utility, testing personnel, and survey teams. Continuous vibration monitoring and real-time oversight ensured that installation activities remained within strict tolerances. Survey data collected before and after installation confirmed that the force main experienced no measurable movement. The Fuller Pile installation process enabled efficient sequencing, allowing the team to mobilize, install all 76 piles, and demobilize within a one-week timeframe, minimizing disruption within the active right-of-way while maintaining full compliance with all project requirements.

The outcome

• Zero measurable movement of the 48-inch force main before and after installation
• No damage or service interruption to the existing utility
• Full compliance with NJDOT requirements and continuous oversight protocols
• Successful coordination between NJDOT, local utility, testing agency, and survey team
• All 76 FP450 piles were installed safely within a highly constrained right-of-way
• Project completed in just one week, including mobilization and demobilization
• No vibration-related impacts observed during installation
• Late-stage load change accommodated without schedule delay or redesign impacts

Why this solution worked

This solution was successful because it combined a low-vibration installation method with a highly adaptable deep foundation system that could be tailored in real time to project demands. The Fuller Pile system effectively transferred loads away from the force main, eliminating the risk of settlement or structural distress while maintaining constructability within a tight and highly monitored corridor. Its inherent flexibility allowed the delegated design team to quickly respond to changing load requirements without introducing delays or additional costs. Equally important, the installation process supported precise control and verification through vibration monitoring and survey confirmation, ensuring that performance objectives were not only met but documented throughout construction. Together, these factors provided a reliable, efficient, and risk-mitigated solution ideally suited for critical utility protection under active roadway infrastructure.