18.—(1) Any authorised activity which takes place on land within the Order limits (whether the activity is undertaken by the undertaker, by its successor pursuant to a transfer or lease under article 7 of this Order, by any person deriving title under them or by any of their servants or agents) is authorised by this Order for the purposes of this article if it is authorised by the Order apart from this article and done in accordance with the terms of this Order, notwithstanding that it involves—
(a)an interference with an interest or right to which this article applies; or
(b)a breach of a restriction as to the user of land arising by virtue of a contract.
(2) In this article “authorised activity” means—
(a)the erection, construction or carrying out, or maintenance of any building or work on land;
(b)the erection, construction, or maintenance of anything in, on, over or under land; or
(c)the use of any land.
(3) The interests and rights to which this article applies are any easement, liberty, privilege, right or advantage annexed to land and adversely affecting other land, including any natural right to support and include restrictions as to the user of land arising by the virtue of a contract having that effect.
(4) Where any interest or right to which this article applies is interfered with or any restriction breached by any authorised activity in accordance with the terms of this article the interest or right is extinguished, abrogated or discharged at the time that the interference or breach in respect of the authorised activity in question commences.
(5) In respect of any interference, breach, extinguishment, abrogation or discharge in pursuance of this article, compensation—
(a)is payable under section 7 or 10 of the 1965 Act; and
(b)is to be assessed in the same manner and subject to the same rules as in the case of other compensation under those sections where—
(i)the compensation is to be estimated in connection with a purchase under that Act; or
(ii)the injury arises from the execution of works on or use of land acquired under that Act.
(6) Nothing in this article is to be construed as authorising any act or omission on the part of any person which is actionable at the suit of any person on any grounds other than such an interference or breach as is mentioned in paragraph (1).
(7) This article does not apply in respect of any agreement, restriction, obligation or other provision contained in a deed made pursuant to section 106 of the 1990 Act or section 278 of the 1980 Act.