Buncombe County, NC Environmental Rules: Stormwater Management (2026)

A stormwater permit from Buncombe County Planning and Development is required for all development or redevelopment equal to or exceeding one acre of residential development, or on commercial lots of one acre or more, under Sec. 26-322(a). Several activities are exempt regardless of size, including commercial development under one acre with total disturbance under one acre, residential development disturbing less than one acre, and land with a vested right recognized before the stormwater ordinance took effect, all under Sec. 26-303. Once a permit is required, the design standard depends on density: low-density projects, defined as two dwelling units per acre or 24 percent built-upon area or less, must keep the post-development peak runoff rate for a one-year, 24-hour storm at or below the pre-development rate and keep all built-upon area at least 30 feet from perennial and intermittent streams, under Sec.

26-362(b)(1). High-density projects above that threshold must instead capture and treat the difference in runoff volume between pre- and post-development conditions for the same one-year, 24-hour storm, draw that volume down over 48 to 120 hours, and remove at least 85 percent of total suspended solids on average annually, while observing the same 30-foot stream buffer, under Sec. 26-362(b)(2). Planning and Development must act on a complete application within 30 days, and forwards a copy to the county soil and water conservation district for a 20-day review, under Sec.

26-322(h)-(i). A denied or modified plan can be appealed to a local plan review committee, then to the board of adjustment, and finally to superior court, under Sec. 26-322(j)-(n). Long-term maintenance of stormwater devices must be recorded against the property and, where a homeowners association is responsible, membership in that association is mandatory for every served parcel, under Sec. 26-385(6).