Inspection of structures in the coastal area is undertaken due to:

• age of the structure.
• deterioration, rusting or degradation of the structure.
• effects of collision or impact on the structure.

• use of a dive team.
• free diving from the surface by an engineer.
• removal of the structure to dry land or on board ship, and inspection.

A dive team inspection uses a professional three person dive team, including a diver, standby diver and dive supervisor. The diver has a video camera and communications to the surface, where there is an engineer directing the work and recording equipment for the video system. Some minor work is generally available (dependent on conditions) such as cleaning small areas, checking bolts, checking integrity of paint work etc. This method of inspection is often used as it offers the safest, most professional service. Operations are generally undertaken from a suitable dive tender boat. If the structure is in a safe area, close to the surface and in good water visibility, the inspection may be undertaken by an engineer free diving from the surface, generally at low tide. This greatly reduces the cost, but is limited in where it can be used.

Water quality varies greatly between projects, and often dictates the methods used. In some areas (such as the River Murray), underwater inspection can only be undertaken by feel.

In some cases, it may be possible and advantageous to remove the structure to dry land, which will allow cleaning, closer examination and repair.