13.—(1) Before beginning to construct any specified work, Network Rail must submit to the lead local flood authority plans of the specified work and such further particulars available to it as the lead local flood authority may within 28 days of the submission of the plans reasonably require.
(2) Any such specified work must not be constructed except in accordance with such plans as may be approved in writing by the lead local flood authority, or determined under paragraph 20.
(3) Any approval of the lead local flood authority required under this paragraph—
(a)must not be unreasonably withheld or delayed;
(b)is deemed to have been given if within 2 months of the submission of the plans for approval or receipt of further particulars if such particulars have been required by the lead local flood authority—
(i)it is neither given nor refused; or
(ii)in the case of a refusal, a statement of the grounds of refusal has not been provided; and
(c)may be given subject to such reasonable requirements as the lead local flood authority may make for the protection of any drainage work.
(4) The lead local flood authority must use its reasonable endeavours to respond to the submission of any plans before the expiration of the period mentioned in sub-paragraph (3)(b).