A citywide Interference current testing project was recently conducted on a small municipality. This city has about 400 miles of water mains and about 28,000 connections. 65 streetlights were releasing AC interference currents due to electrical wiring faults. That is, 1 interference current source for every 6 miles of water main.
11 of those 65 interference currents (17%) were directly linked to water main damage. From the group of 11 subset, the lowest damaging voltage found was 5.2 volts, the highest was 121.
This project did not look at the impact of these currents on the municipal gas pipelines as this data was not available from the local gas utility or public sources.
This survey did not calculate the amps per meter squared at each leak location- but these external interference current voltage sources may be responsible for damaging more municipal water (and possibly gas) distribution systems than previously thought.
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Mark Voigtsberger
Port St Lucie FL
+14253817265
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