Galvanic Cathodic Protection uses the natural activity of materials when placed in a conductive solution. When two different materials are connected, the material which is more active will corrode before the less active material. By connecting the steel, ductile iron, or copper structure to a more active materials such as magnesium or zinc anode, the anode will corrode before the structure.

Galvanic Cathodic protection is typically used in the following situations:

  • when a small amount of current is needed to protect the structure
  • lower resistivity solutions
  • localized area


  • no external power source
  • lower maintenance requirements
  • small current output
  • easy to install
  • easier to add anodes
  • minimum right-of-way/easement costs


  • low driving current
  • lower efficiency
  • bare structures could require many anodes