Explain the Damage inspections - underwater inspection of bridge?

Sometimes referred to as post-event inspections, damage inspections are typically unscheduled inspections aimed at rapidly assessing the stability of a structure in the event of structural damage resulting from environmental or man inflicted causes.

The scope of inspection can vary substantially by the type and severity of event. Inspection must be sufficient to determine the need for emergency load restriction or closure of bridge to traffic and to assess the level of effort necessary to repair the damage. If measurable damage has occurred, inspections must evaluate section loss, misalignment of members, and loss of foundation support if any.