North American Benchmark Study Comparing CCTV Vs. FELL Inspection On 322 Gravity Sewer Mains

This case study presents key findings and the executive summary for a first-of-its-kind 14-mile North American pipeline benchmark study, comparing Closed-Circuit Television (CCTV) inspection against Focused Electrode Leak Location (FELL) inspection results. Both inspection techniques were completed by the same national pipeline contractor.

The project was conducted between August 2019 and March 2020, which assessed 322 gravity sewer mains, totaling 74,000 linear feet (LF), and included over 1,800 customer tap connections to the sewer mains. This benchmark is the first major evaluation of its kind to identify infiltration sources by comparing more conventional CCTV inspection results to innovative FELL inspection.