34.—(1) The Agency may operate the barrier and among other things may—
(a)open or close the barrier; and
(b)regulate water levels in the river by means of the scheduled works.
(2) The power conferred in paragraph (1) is to be exercised so as to safeguard and improve the environment and amenities of the river.
(3) Paragraph (2) does not prevent the exercise of the power contained in paragraph (1) in order—
(a)to prevent or alleviate any emergency;
(b)to release flood water;
(c)to ascertain the safest and most effective ways of using the scheduled works, to test its working or to train staff in its operation;
(d)to facilitate the construction, maintenance or re-laying of any works in or beside the river; or
(e)to secure and maintain satisfactory navigation in the vicinity of the scheduled works and the river.
(4) When operating the barrier the Agency must have regard to—
(a)the safety of vessels in the river;
(b)the requirements of vessels in the river (including the need to have freedom of access to moorings and berths in the river upstream of the barrier);
(c)the desirability of developing and conserving flora and fauna in the river; and
(d)any reasonable request of—
(i)A.B. Ports or other navigation authority for the time being for or in connection with their functions; and
(ii)the police or other emergency services.
(5) Subject as otherwise expressly provided in this Order, no liability arises in respect of any costs, damages, losses or expenses incurred by any person as a direct or indirect result of—
(a)any obstruction to, delay of, or other interference with the passage of vessels; or
(b)any change in the level of water in the river,
occasioned by the operation of the scheduled works unless the costs, damages, losses or expenses are incurred by reason of negligence in their operation.