Union County, NC Landscaping Rules: Rainwater Harvesting (2026)

050's Table 100-1, Permitted Setback Obstructions, lists rainwater harvesting equipment that projects no more than 4 feet into the setback alongside similar small encroachments such as eaves, chimneys, bay windows and geothermal heat pumps that the UDO allows to intrude a few feet into an otherwise unoccupied setback. Setbacks in unincorporated Union County are otherwise required to stay unobstructed and unoccupied from the ground to the sky, so without this listed exception a cistern, rain barrel stand or catchment tank installed close to a lot line would have to meet the full street, side or rear setback that applies to the house itself, which under Table 5-2 runs from 20 to 40 feet on the street/front line and 5 to 15 feet on the side, depending on the zoning district.

Because the 4-foot allowance is measured from the setback line rather than from the property line, a rainwater system mounted near the side of a house that already meets its own setback gains extra room to project outward without pushing the whole structure into the setback. The ordinance does not set a separate size, capacity or height limit on the equipment itself, only the 4-foot maximum intrusion into the setback.