Sewer inspection system outperforms CCTV

Plumbers and sewer utilities have traditionally used closed-circuit television (CCTV) cameras to inspect sewers. Unfortunately, CCTV relies on subjective visual observations which are unreliable in finding leaks.

In contrast, a system from Electro Scan (Sacramento, CA, USA) automatically finds leaks by measuring the variation of electric current passing through a pipe’s wall to locate cracks, fractures, defective joints, and faulty taps.

Now, the company claims that an independent EPA-sponsored field demonstration has actually showed that the electro scan technology is more effective than CCTV at finding and quantifying leaks in sewers. The field demonstration was conducted in August 2010 and was hosted by Kansas City, MO Water Services Department.

Five technologies were selected for the field trials: zoom camera, electro-scanning, digital scanning, laser profiling, and sonar, which were all compared to CCTV inspection. Each technology identified defects by collecting data or images of the pipe condition.

A copy of the report is available here.

-- by Dave Wilson, Senior Editor, Vision Systems Design