Whenever a water resource board discovers or ascertains that the county, a township, or city therein, or that any tract, parcel, or piece of land is being benefited by a project and that the county or such township, municipality, tract, piece, or parcel of land was not included in the project area assessed for the cost of construction and maintenance of the project when established, the board shall commence proceedings for reassessment of lands originally assessed for the cost of establishing and constructing such project and shall apportion and assess the part of the balance remaining unpaid, if any, of the cost of such project, and the expense of maintenance, which such county, township, or city and each tract of land found benefited thereby should bear.

Before making such reassessment or reapportionment of benefits, the board shall hold a hearing for the purpose of determining the benefits of the project to the county, such township, or city and to each tract, piece, or parcel of land being benefited. At least ten days’ notice of the hearing shall be given by publication in the newspaper or newspapers having general circulation in the county and by mailing notice thereof to each owner of land assessed for the cost of construction and maintenance when the project was established, and by mailing such notice to the governing body of the county, township, municipality, and to the owner, as determined by the records in the office of the recorder or county treasurer of each tract, piece, or parcel of land found to be benefited since the establishment of the project. The provisions of this chapter governing the original determination of benefits and assessment of costs shall apply to the reassessment and assessment of benefits carried out under the provisions of this section.