18.—(1) Any street to be constructed under this Order shall be completed to the reasonable satisfaction of the highway authority and shall, unless otherwise agreed, be maintained by and at the expense of Network Rail for a period of 24 months from its completion and at the expiry of that period by and at the expense of the highway authority.
(2) Where a street is altered or diverted under this Order, the altered or diverted part of the street shall when completed to the reasonable satisfaction of the street authority, unless otherwise agreed, be maintained by and at the expense of Network Rail for a period of 24 months from its completion and at the expiry of that period by and at the expense of the street authority.
(3) Paragraphs (1) and (2) do not apply in relation to the structure of any bridge or tunnel carrying a street over or under any railway of Network Rail.
(4) Except as provided in this article and notwithstanding anything in section 46 of the Railways Clauses Consolidation Act 1845(1) as incorporated in this Order, Network Rail shall not be liable to maintain the surface of any highway under or over which the scheduled works shall be constructed, or the immediate approaches to any such highway.
(5) Nothing in this article shall prejudice the operation of section 87 of the Street Works Act (prospectively maintainable highways); and Network Rail shall not by reason of any duty under this article to maintain a street be taken to be the street authority in relation to that street for the purposes of Part 3 of that Act.
(6) Nothing in this article shall have effect in relation to street works as respects which the provisions of Part 3 of the Street Works Act apply.