If there is a Sanitary Sewer Overflow (SSO) problem, Electro Scan can find the source. Electro Scan identifies and measures ALL pipe defects that cause leaks. On average, typical visual inspections using CCTV inspections miss 2 out of 3 defects; oftentimes, mis-interpreting or mis-cataloging larger defects, making it impossible for engineers to prioritize pipe segment that should be rehabilitated. In contrast, Electro Scan provides a complete data set, without the need of visual assessment, indicating the type of defect, its location, and relative size. Relying on electro scan, the worst ten percent (10%) of pipe segments analyzed can be accurately and reliably targeted for rehabilitation. Electro Scan should be used as a new standard to warranty all repairs, rehabilitation, and replacement projects.
The ASTM Standard F2550-13 “Standard Practice for Locating Leaks in Sewer Pipes Using Electro-Scan–the Variation of Electric Current Flow Through the Pipe Wall” provides a blueprint for implementing an Electro Scan project, including: Contract responsibilities, principle of operation, apparatus specification, specification of information and data to be reported and detailed procedure. To purchase and download a copy of the ASTM standard click on the following link to the ASTM standard by clicking on the following link ASTM Standard F2550-13.
The U.S. EPA* sponsored a five-day field demonstration in Kansas City (MO) that compared Electro Scan with CCTV. The report was published in July 2011 and stated that “Electro-scan technology can be used to estimate the magnitude and location of potential leaks along a pipeline, helping utilities better understand and control sources of infiltration/exfiltration. It directly measures leak potential, independent of external conditions that are temporal in nature (e.g., seasonal, wet weather). Its use of direct measurements provides a quantitative analysis of leak potential without relying on visual observation.” The demonstration showed that sewer electro-scan identified 2.4 times more defects that can leak than CCTV.
For more information, download a copy of the EPA Benchmark report by clicking on the following link U.S. EPA Benchmark Study.
*The U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, Water Supply.
Over 500,000 linear feet of sewer main inspection has benefited from electro scan. Investor-owned and municipal utilities that have used electro scan include American Water Works, Inc., Louisville and Jefferson County Metropolitan Sewer District, City of Pasadena (Texas), City of Redding (California), and Sacramento Regional County Sanitation District (California).
Electro Scan measures the variation of electricity passing through the pipe wall. Electricity does not pass through non-metallic sewer pipe walls. Electricity will pass through a pipe defect that can leak water. The bigger the defect the larger the electricity flow.
6. Do you have to fill the entire sewer main, manhole to manhole, in order for electro scan to work?
No. Water in the sewer main is what provides the electrical connection between the Electro Scan probe and the pipe wall. To Electro Scan the complete circumference of a pipe, it only must be full of water at the location of the probe. This can generally be achieved by using a funnel plug that creates a moving reservoir of water with the probe.
For large pipes the existing flow level can be used as long as it is realized that only that part of pipe submerged is Electro-scanned.
For sewer laterals, it is best to submerge the entire segment of the pipe, from the sewer clean-out to close to the mainline sewer connection.
Yes. The voltage between the probe and the surface electrode is about 10 volts and the current is limited to 40 milliAmp, so there is no chance of spark or electric shock, and therefore, safe for humans even in the event of a cable break or a short circuit.
No. The two inspection methods require different pipe conditions. CCTV inspection is best utilized during low flow or no flow conditions, so an operator is able to view and record the entire circumference of the pipe. In contrast, Electro Scan requires the pipe to be full at the location of the probe. Since the probe used for the ES-660™ for Sewer Mains is pulled through a sewer main by a cable, Electro Scan recommends disconnecting the CCTV camera and attaching the ES-660™, instead.
Electro Scan data covers every inch of a pipe. Once raw data is captured, a series of sophisticated algorithms are run to validate the data. Once processed, the user can either generated a report of pipe defects or upload the data to Electro Scan’s Critical Sewer™ Cloud Computing application, to further refine the data to map directly to the pipe’s joints and other pipe features.It can generate side-by-side comparisons to past CCTV inspection results to show key differences. As an option, municipal and investor-owned utilities may partner with Electro Scan to develop custom web service applications to make available data to their internal systems.
No. Critical Sewers™ is a software-as-a-service application, offered on a monthly subscription basis, with partnering agreements available to create bi-directional integrations with your existing systems.
Legacy sewer inspection techniques, such as CCTV, smoke testing, dye flood testing, and sonar, are not effective at r finding defects that are sources of infiltration/exfiltration, and therefore are not appropriate to certify post-rehabilitation projects.
In the case of pipe relining projects, the most difficult task is re-connecting service laterals while maintaining the water tightness of the liner. CCTV cannot effectively examine the water tightness of this connection. Electro Scan readily detects the potential of water flowing through the lateral connection and the connection of the liner to the manhole.
The same is true for post-grouting projects. According to ASTM 2304-03, Standard Practice for the Rehabilitation of Sewers Using Chemical Grouting, and ASTM 2454-05, Standard Practice for Sealing Lateral Connections and Lines from the Mainline Packer Method, Using Chemical Grouting, a seal is not achieved by simply placing an internal grout ring. Grout must be placed outside the joint. This is not able to be verified by a CCTV camera. Again Electro Scan is able to determine water tightness of a grouted joint.
Yes. Electro Scan has developed a 4-in-1 solution for find and measure leaks in pressurized water mains. Available in 2021, exclusively as a service from Electro Scan, the reliable and repeatable solution provides results from 4 technologies: low voltage conductivity (Electro Scan), HD CCTV, acoustic sensor, and pressure sensor.
Yes. The electric current used by Electro Scan to identify leaky pipe defects has a frequency that is detectable by commonly used pipe/cable locators. By connecting the ground of the pipe locator to the ground of the probe, the pipe can be located on the surface from the pipe entry to the probe position.