Planning commission recommends RM‑6 zoning amendments to city council, backs universal 15‑foot rear setback

On July 10, 2025, the Riverton City Planning Commission voted unanimously to recommend that the Riverton City Council approve amendments to Section 18.45 (RM‑6 residential zone) to reinsert standards for private roads, clarify minimum lot-area calculations and set a uniform 15‑foot rear-yard setback.

Staff presented proposed changes (PLC-25-5005) intended to restore private‑road design standards that were removed from the RM‑6 text when multifamily standards were previously revised. The commission’s recommendation asks city council to adopt the staff-drafted ordinance amendments and to set rear-yard setbacks to 15 feet regardless of the zoning that borders a parcel.

Planner Tim (city staff) told commissioners the RM‑6 amendments would: reestablish private‑road cross-sections, specify two private‑road pavement-width categories (20 feet for one‑ or two‑lot roads; 26 feet where three or more lots share a private road), require fire access and turnarounds, and allow the planning commission to require connections to adjacent properties. Staff emphasized one substantive drafting choice: private‑road area would not be counted toward a lot’s 5,000‑square‑foot minimum. As staff illustrated, counting a private road as part of a 5,000‑square‑foot lot can reduce buildable area dramatically — examples used by staff showed buildable areas shrinking to about 1,760 square feet on a narrow/deep lot and about 1,260 square feet on a wide/shallow lot if the private road were included in lot area.

"Private roads cannot cut off access to other properties," Tim said, describing how the commission could require cross‑connectivity and limit curb cuts on major corridors such as Redwood Road. He also explained that the code would still prefer public streets when feasible but allow private roads by conditional use where public streets are impractical.

Commissioners debated whether the RM‑6 changes would yield more-affordable housing. Several members said the standard as written could enable smaller lots and more infill but that market forces and builder preferences may produce higher‑end product rather than lower‑cost homes. Commissioner Cannon raised concerns about off‑street parking and suggested wider driveways or other measures to reduce on‑street parking. Commissioner Clough referenced state legislation under which municipalities may not require a garage for certain owner‑occupied affordable units, noting the law's caveats and enforcement questions.

After discussion, Commissioner Clough moved that the commission recommend approval of the RM‑6 amendments as drafted and add a recommendation that rear setbacks be set at 15 feet citywide for RM‑6; Commissioner Matheson seconded the motion. The planning commission voted unanimously to send the recommendation to city council.

Staff flagged additional implementation questions for council consideration or for later refinement by the commission, including whether to allow private‑road area to count toward minimum lot size in some cases, whether to retain a two‑car garage requirement, and how to balance infill development with the character of adjacent single‑family neighborhoods.

The item is legislative; the planning commission’s action sends the ordinance amendment and the commission’s recommended revisions to the Riverton City Council for final action.