The expenses under this or any other Act of the drainage board for an internal drainage district (including any contribution made by the board towards expenses of the appropriate supervisory body) shall, in so far as they are not met by contributions from the appropriate supervisory body, be raised by means of—
drainage rates made by the board under and in accordance with Chapter II of this Part or, in relation to any time before 1st April 1993, the provisions saved by virtue of paragraph 15 of Schedule 2 to the Water Consolidation (Consequential Provisions) Act 1991; and
special levies issued by the board under and in accordance with regulations made under section 75 of the Local Government Finance Act 1988.
The expenses of a drainage board which are raised by means of drainage rates in respect of the financial year beginning in 1993 and subsequent financial years shall be defrayed out of such rates without regard to the purpose for which any such expenses were incurred.