(1)A local authority shall not carry out or maintain any drainage works authorised by sections 14 to 16 above in connection with any watercourse except with the consent of, and in accordance with any reasonable conditions imposed by, the NRA.
(2)Before giving any consent or imposing any condition under subsection (1) above with respect to any drainage works in connection with a watercourse under the control of an internal drainage board the NRA shall consult with the internal drainage board.
(3)A consent required under subsection (1) above—
(a)shall not be unreasonably withheld; and
(b)shall be deemed to have been given if it is neither given nor refused within two months after application for it is made.
(4)Any question arising under this section whether the consent of the NRA is unreasonably withheld, or whether any condition imposed by the NRA is reasonable, shall be referred to and determined by the Ministers.
(5)Subsection (1) above shall not apply to any work carried out in an emergency, but a local authority carrying out any work excepted by this subsection shall, as soon as practicable, inform the NRA in writing of the carrying out of the work and of the circumstances in which it was carried out.