Project #1460

Sewer Lateral Electro Scan Field Verification Pilot

Principal Investigator
Research Manager
Mr. Walter L Graf, Jr.
Milwaukee Metropolitan Sewerage District
Asset Management
Condition Assessment
Sanitary Sewer Overflows (SSOs)
Groundwater Management & Protection


This project field tested an emerging technology, Electro Scan, which is designed to inspect sewer laterals to find defects that allow infiltration of groundwater. The Electro Scan technology involves passing an electrical probe through a pipe filled with water. The probe emits a focused electrical beam that is able to pass through defects in the pipe wall into the surrounding soil, complete an electrical circuit with a ground rod. The significance of the electrical signal suggests the degree of the infiltration defect. Over 100 laterals were tested in the City of Wauwatosa, Wisconsin. These tests were then compared to information concerning the condition of the laterals, including internal television inspection, infiltration rates produced in a rainfall simulation test, and water exfiltration rates. The results of these comparisons, lessons learned, and costs related to the testing are presented in the report. Published by WERF. 122 pages. Online PDF. (2013)

Originally funded as WERF project INFR4R12.