Protecting marine structures from corrosion

The protection of metal marine structures against corrosion in a sense presents greater problems than that of protecting ships themselves, since they cannot be hauled out of the water for inspection and overhaul. Buoys, jetties, piers, bridges in tidal waters and, more recently, oil rigs, are all exposed to the most severe corrosion conditions. There are three types of condition to be considered in any one structure—the parts which are always above the water line, those which are covered by water only at high tide, and those which are permanently underwater.