Utah Code § 10-20-408

(1) Municipalities may adopt an official map. (2) (a) An official map does not: (i) require a landowner to dedicate and construct a street as a condition of development approval, except under circumstances provided in Subsection (2)(b)(iii); or (ii) require a municipality to immediately acquire property it has designated for eventual use as a public street. (b) This section does not prohibit a municipality from: (i) recommending that an applicant consider and accommodate the location of the proposed streets in the planning of a development proposal in a manner that is consistent with Section 10-20-911; (ii) acquiring the property through purchase, gift, voluntary dedication, or eminent domain; or (iii) requiring the dedication and improvement of a street if the street is found necessary by the municipality because of a proposed development and if the dedication and improvement are consistent with Section 10-20-911.