Zinc anodes offer a sacrificial method of maintaining the steelwork of the pier.. The anodes 'attract' corrosion thereby extending the life and protecting the steel work. (same as on ships hulls etc)

Zinc anodes can help protect buried water tanks or any buried steel structure from external corrosion. The use of zinc anodes protect a structure from corrosion by a principle is known as cathodic protection. Corrosion is an electrochemical reaction where the reaction can be separated into two halves (two half-cell reactions): the anodic and the cathodic reactions. Deterioration (or corrosion) of the metal occurs at the anode. When zinc is in electrical contact with the steel and immersed in the same liquid, the zinc become the anode and the steel structure becomes the cathode. The zine is preferentially corroded, leaving the steel structure protected.

To protect a steel tank, the anodes should be buried and evenly distributed around the tank. Deep anodes are sometimes needed to protect tanks with large flat bottoms. The holes around the anode are often filled with carbon to ensure good electrical contact with the ground water. Electric cables need to connect the zinc anodes to the steel.

The anodes do not protect against internal corrosion of the tank.

Aluminum and zinc are close enough not to cause too much trouble. In highly electrolytic solutions there will be a voltage potential between them.

Different metals should be avoided if at all possible when in contact with water or solutions.

K. F. Lorking has written:

'Inhibition of corrosion of magnesium and zinc in chromate solutions' -- subject(s): Chromates, Corrosion, Magnesium, Zinc

'The corrosion of zinc' -- subject(s): Corrosion, Zinc

'Some electrode processes on copper anodes in orthophosphoric acid solutions'

Zinc or Aluminium anodes are often used to stop iron struts on oil rigs from corroding due to salt water.