County adds Thistle/Schertz canyon parcels to natural‑hazards overlay after UGS input

Brandon Morrison, community development staff, outlined a proposed amendment to the land‑use ordinance to add portions of the Thistle Slide and Schertz Canyon Slide areas to the county’s natural‑hazards overlay. Morrison said the change responds to UGS mapping and an inquiry that suggested up to 700 lots might be considered for development in the area, prompting closer review.

Staff clarified the overlay does not prohibit development but requires a natural‑hazard assessment for proposals to build habitable structures, subdivisions or critical facilities; mitigation must be incorporated where the assessment identifies it. Morrison told commissioners staff used UGS map data (2010 series) and the Utah Geological Survey participated in planning‑commission consideration.

Landowners had asked for more time to prepare studies; commissioners and the county attorney noted landowners may later submit parcel‑specific hazard assessments to demonstrate that mitigation is unnecessary and that the commission could carve parcels out as warranted. After discussion, the commission moved and voted to adopt the ordinance adding the described parcels to the natural‑hazards overlay; the motion carried by voice vote (recorded as 3‑0). The county will apply the overlay to the legal descriptions provided and accept future geotechnical or hazard assessments when submitted.

Next steps: staff will incorporate the ordinance language and legal descriptions into the county code and publish the updated overlay requirements; landowners who provide acceptable assessments may seek parcel removal or mitigation agreements through the normal process.