20 January 2015
Sewer Leak Identification: Electro Scan Compliments CCTV for Inspection
by Don Rigby
Public enemy #1 for managers of sanitary sewer collection systems is infiltration. Groundwater and soil fines enter into mainlines, manholes, laterals, and lateral connections through joints and defects. According to the EPA, nearly half the water entering treatment plant operations is clean groundwater - a direct result from lack of maintenance. CCTV has long been the most reliable technology for inspecting non-man entry underground assets, but experts agree, visual proof is not 100% conclusive. Enter: Electro Scan. As a diagnostic tool, Electro Scan is brilliant technology built on the theory that water conducts electricity, and is well proven to detect leaks whether or not infiltration is active at that time. At the very least, Electro Scan a complimentary technology to CCTV inspection.
In addition to locating and quantifying infiltration in old pipes, Electro Scan can be used to certify new and CIPP relined pipes. However, when it comes to grout, Electro Scan is currently not a recommended validation technology. Water is a vital component in the gel/soil matrix produced by acrylic grouts used to create a positive seal of joints and defects on the outside of the pipe structure. Electro Scan’s probe identifies the presence of water in a sealed joint and reports a false/positive reading. Discussions between Avanti and Electro Scan are underway to enhance the reporting so this technology can be utilized not only to identify, but also to validate with confidence.
We’ll keep you posted on progress, but in the meantime if you have personal experience with Electro Scan, please volunteer your thoughts and we’ll keep the open dialog flowing…