The Mapleton City Critical Environmental Zone includes an allowance for cluster zoning when such zoning will improve ridgeline protection, decrease or not increase environmental hazards, and decrease the cost of infrastructure to the city. While the overall allowed density is not increased, dwellings that have been approved for clustering are allowed an increase in density from one dwelling per three acres to one dwelling per acre. Designed open space in approved cluster development may be owned by the city or an approved non-profit.