In case of damage to, or destruction or decay of, a tidal work or any part thereof excluding the exposure of cables, the undertaker must, as soon as reasonably practicable and no later than 24 hours following the undertaker becoming aware of any such damage, destruction or decay, notify Natural Resources Wales, Trinity House, the Maritime and Coastguard Agency, the United Kingdom Hydrographic Office and the Kingfisher Information Service of Seafish and lay down such buoys, exhibit such lights and take other such steps for preventing danger to navigation as Trinity House may from time to time direct.

In case of exposure of cables on or above the seabed, the undertaker must within three days following identification of a potential cable exposure, notify mariners by issuing a notice to mariners and by informing the Kingfisher Information Service of Seafish of the location and extent of exposure. Copies of all notices must be provided to the Natural Resources Wales, the Maritime and Coastguard Agency, Trinity House, and the United Kingdom Hydrographic office within five days.