Utah County, UT Environmental Rules: Flood Zones (2026)

16 applies to Areas of Special Flood Hazard identified in the FEMA Flood Insurance Study for Utah County (effective June 19, 2020, or as later updated) and the accompanying FIRM map, adopted by reference into the county's records at the County Clerk/Auditor's office. No structure or land use may be constructed, located, extended, converted, altered or developed in one of these areas without full compliance, and 'new construction' is defined as structural work commencing after October 29, 1982. Before any development, grading or construction permit issues, the Floodplain Administrator, who may be assisted by the County Building Official, County Engineer or Zoning Administrator, must find the proposal complies with this section and the underlying zoning district and issue a written clearance; nothing may begin until that clearance and permit are issued.

Inside a mapped Floodway, encroachments including fill, new construction and substantial improvements are flatly prohibited unless a professional engineer licensed in Utah certifies in a written report that the encroachment will not raise flood levels during a base flood discharge, and even then all flood hazard reduction requirements still apply. No manufactured home may be placed in a floodway except in an existing manufactured home park or subdivision. A property owner who disputes being mapped into a one-percent-annual-chance flood area must pursue a FIRM map revision through federal channels; there is no local appeal to redraw the map.

The Appeal Authority may grant variances from the section's size, distance or elevation standards under UCLUO 16, weighing factors such as danger to life and property, availability of alternate sites, and the cost of emergency services during flooding, but a variance can never be granted inside a floodway if it would raise flood levels during a base flood.