20.—(1) The undertaker must at or near—
(a)a tidal work, including any temporary work; and
(b)any plant, equipment or other obstruction placed in connection with the tidal works,
during the whole time of construction, operation, maintenance, repowering and decommissioning exhibit every night from sunset to sunrise and in periods of restricted visibility such lights, if any, and take such other steps for the prevention of danger to navigation as the Welsh Ministers or Trinity House may from time to time direct.
(2) After the completion of construction or repowering of a tidal work, the undertaker must at the outer extremity of it exhibit every night from sunset to sunrise and in periods of restricted visibility such lights, if any, and must take such steps, if any, for the prevention of danger to navigation as Welsh Ministers or Trinity House may from time to time direct.