Board discusses stray electrical currents after boat owners report accelerated zinc loss

The Petersburg Borough Harbor Board discussed complaints May 27 from vessel owners that sacrificial zinc anodes are disappearing at an increased rate at parts of the floats, raising concern about stray electrical currents or degraded grounding connections.

A board member said multiple boat owners reported the problem, noting the lower parts of C and D floats and an area described as Seaflo seem to be “getting hotter” and that inboard zincs have been disappearing more quickly over the last three years.

Board members and the harbor master said the issue could be caused by biological growth on grounding straps that reduces conductivity, corroded grounding connections, or stray currents. The harbor master suggested dock cleaning and inspection of grounding straps as a first step to identify causes and encouraged owners to report specific incidents so staff can investigate.

No remediation plan beyond inspection and cleaning was approved at the meeting; staff will include grounding‑strap checks in routine dock inspections and follow up with specific findings and recommended repairs if abnormalities are identified.