The locality shall refund any impact fee or portion thereof for which construction of a project is not completed within a reasonable period of time, not to exceed fifteen years. In the event that impact fees are not committed to road improvements benefiting the impact fee service area within seven years from the date of collection, the locality may commit any such impact fees to the secondary or urban system construction program of that locality for road improvements that benefit the impact fee service area.

Upon completion of a project, the locality shall recalculate the impact fee based on the actual cost of the improvement. It shall refund the difference if the impact fee paid exceeds actual cost by more than fifteen percent. Refunds shall be made to the record owner of the property at the time the refund is made.