If the drainage board for any internal drainage district are of the opinion that the amount of the annual value of any chargeable property in that district should be increased or reduced, having regard to changes in the relevant circumstances, for the purpose of securing that the burden of the drainage rates payable in respect of all chargeable properties in the district is fairly distributed so far as reasonably practicable among the persons liable to pay those rates, the board may make a determination of annual value under this section.
If the occupier of any chargeable property in a drainage district is of the opinion that, having regard to changes in the relevant circumstances, the amount of the annual value of the property should be altered for the purpose mentioned in subsection (1) above—
A determination of annual value under this section shall be a determination in accordance with section 44 below specifying as the annual value of the chargeable property in question such greater or smaller amount than the amount of the annual value as the board, having regard—
consider just for the purpose mentioned in subsection (1) above.
For the purposes of this section a change in the relevant circumstances, in relation to any chargeable property, is a change in the circumstances by reference to which the annual value of the property in question, or of any other chargeable property in the district in question, was fixed.