Utah Code § 11-36a-602
§ 11-36a-602. Expenditure of impact fees.
(1) A local political subdivision may expend impact fees only for a system improvement: (a) identified in the impact fee facilities plan; and (b) for the specific public facility type for which the fee was collected. (2) (a) Except as provided in Subsection (2)(b), a local political subdivision shall expend or encumber an impact fee collected with respect to a lot: (i) for a permissible use; and (ii) within six years after the impact fee with respect to that lot is collected. (b) A local political subdivision may hold the fees for longer than six years if it identifies, in writing: (i) an extraordinary and compelling reason why the fees should be held longer than six years; and (ii) an absolute date by which the fees will be expended.