Indiana Code Title 14. Natural and Cultural Resources § 14-26-8-51

Sec. 51. (a) The county surveyor in charge of a project established under this chapter shall, within ten (10) days after letting the contract for construction, carefully compute the entire cost of the improvement, including the following:

(b) The county surveyor shall apportion the costs and expenses to the tracts of land assessed in proportion to the total assessment against the respective parcels of land benefited by the construction of the work.  The apportionment to the respective tracts or parcels of land may not exceed the benefits assessed against the tracts or parcels, respectively.

(c) The county surveyor shall certify the assessments, apportionments, and time to make payments to the county auditor.  If the improvement affects the landowners in more than one (1) county, the county surveyor shall certify the assessments, apportionments, and time to make payments to the auditor of each other county affected.