Cal. Water Code § 8802

At the time appointed, or such other time to which the hearing may be postponed, or which may be appointed by the board, the board shall hear any objections to the reapportionment and shall approve, modify, or alter the reapportionment in such manner as in their judgment will charge each of the smaller parcels with a just proportion of the assessment made upon the tract subdivided and shall enter an order on its minutes accordingly.