11.—(1) Subject to sub-paragraphs (2) and (3), if by reason or in consequence of the construction of any such works authorised by this Part or in consequence of the construction, use, maintenance or failure of any of the authorised development by or on behalf of the undertaker or in consequence of any act or default of the undertaker (or any person employed or authorised by the undertaker) in the course of carrying out such works, including without limitation works carried out by the undertaker under this Part or any subsidence resulting from any of those works, any damage is caused to any apparatus or alternative apparatus (other than apparatus the repair of which is not reasonably necessary in view of its intended removal for the purposes of those works) or property of a protected person, or there is any interruption in any service provided, or in the supply of any goods, by any protected person, or the protected person becomes liable to pay any amount to any third party, the undertaker must—
(a)bear and pay on demand the cost reasonably incurred by that protected person in making good such damage or restoring the supply; and
(b)indemnify that protected person for any other expenses, loss, demands, proceedings, damages, claims, penalty or costs incurred by or recovered from the protected person, by reason or in consequence of any such damage or interruption or the protected person becoming liable to any third party.
(2) The fact that any act or thing may have been done by a protected person on behalf of the undertaker or in accordance with a plan approved by a protected person or in accordance with any requirement of a protected person or under its supervision does not (subject to sub-paragraph (3)) excuse the undertaker from liability under the provisions of sub-paragraph (1).
(3) Nothing in sub-paragraph (1) imposes any liability on the undertaker with respect to any damage or interruption to the extent that it is attributable to the neglect or default of a protected person, its officers, servants, contractors or agents.