During a planned maintenance outage at a major 30-million-gallon-per-day (MGD) coastal New Jersey water treatment plant, inspection revealed severe corrosion and structural deterioration of a carbon-steel clarifier feed well. Constant exposure to turbulent flow, abrasive particles, and corrosive water treatment conditions had caused extensive metal loss, wall thinning, pinholing, and heavy scale buildup throughout the well panels, vanes, and support beams. The deterioration had progressed to the point that the clarifier was removed from service, reducing the plant's available treatment capacity until repairs could be completed.
Replacing the clarifier well would have significantly increased project costs, extended downtime, and required lengthy fabrication. Instead, the facility's heavy civil construction contractor engaged Banks Industrial Group (BIG) as a specialty repair contractor to perform an in-place clarifier repair, restoring the structure during the scheduled outage.
How BIG Completed the Repair
With cranes and aerial lifts unable to access the work area, BIG overcame significant access constraints by engineering and erecting a specialized scaffold system inside the clarifier, providing safe access to the damaged structure. Technicians then prepared the deteriorated steel, rebuilt areas of metal loss using Belzona repair composites, and restored structural integrity to the complex well panels, vanes, support beams, and cylindrical sections using the Belzona SuperWrap II composite repair system. Finally, the restored structure was encapsulated and protected with Belzona 5812 DW, an NSF-approved protective coating for potable water immersion service, providing long-term corrosion protection. The entire restoration was completed without welding, hot work, or costly component replacement.
Results for Contractor and Facility
The restored clarifier was returned to service, allowing the facility to regain treatment capacity while extending the service life of a critical asset. For water utilities, consulting engineers, and heavy civil contractors, this project demonstrates how specialized composite repair techniques can restore critical infrastructure during planned maintenance outages—
avoiding unnecessary replacement, minimizing downtime, and helping maintain reliable, compliant plant operation.
