Water Resources Act 1991

10 (1) The Authority may, as respects any drainage charge raised by it for the current or the preceding year, make such amendments in any demands or other documents relating to the charge as appear to the Authority necessary in order to make the raising, levying and collection of the charge conform with this Act.

(2) In particular, the Authority may—

(a) correct any clerical or arithmetical error;

(b) correct any erroneous insertions or omissions or any misdescriptions;

(c) make such additions or corrections as appear to the Authority to be necessary by reason of any change in the occupation of any chargeable land or any property ceasing to be chargeable land.

(3) The Authority shall serve a notice of any amendment made by the Authority in pursuance of this paragraph on the occupier of all land affected thereby.

(4) Where an amendment is made in pursuance of this paragraph—

(a) any amount overpaid shall be repaid or allowed; and

(b) any amount underpaid may be recovered as if it were arrears of the charge.