Nothing in this Act shall affect prejudicially any estate, right, power, privilege or exemption of the Crown, or authorise the apportionment of any part of the cost of carrying out a scheme to, or the recovery of any part of the cost of maintaining drainage works in respect of, any lands (including tidal lands below the high-water mark of ordinary spring tides) belonging to His Majesty in right of his Crown or to any Government Department, and nothing in this Act shall authorise the use of or interference with any lands (including as aforesaid) belonging to His Majesty in right of his Crown, without the consent of His Majesty or the Government Department, as the case may be.