NC Outstanding Resource Waters (ORW) and High-Quality Waters (HQW) Standards (NC)

Tracked preemption from the North Carolina overlay bundle.

Overview

Effective
1989-09-01
Sunset
Authority
state
Scope
state:NC

Trigger predicate

When this evaluates true for a parcel, the law's preempted fields take precedence over base zoning.

parcel.in_orw_hqw_basin == True

Preempted fields

4 fields on the base district schema are rewritten when the trigger fires.

FieldOpValueNote
base_districts[*].impervious_surface_max_pctcap_at12ORW low-density: ≤12% BUA OR 1 du/ac with no curb/gutter
base_districts[*].impervious_surface_max_pctcap_at12HQW low-density: ≤12% BUA; high-density option allows higher with 85% TSS removal and other controls
base_districts[*].stormwater_treatment_requiredrequire85_pct_TSS_and_runoff_volume_matchHQW/ORW high-density option requires 85% TSS removal AND match pre-development hydrology
base_districts[*].riparian_buffer_ftfloor_at3030-ft minimum buffer; 50 ft in ORW shellfish areas

Citation

Authority source
15A NCAC 02B .0224 (ORW); 15A NCAC 02B .0101 (HQW); NCGS §143-214.1
§ 15A NCAC 02B .0101 / .0224
https://files.nc.gov/ncdeq/Water%20Quality/Surface%20Water%20Protection/CSU/Surface%20Water%20Classifications/15A_NCAC_02B_.0200.pdf

Research notes

Outstanding Resource Waters and High-Quality Waters are NC EMC surface-water classifications conferring stricter stormwater and buffer requirements. ORW examples: portions of Tar-Pamlico, New River, Lumber, Eno, Watauga, several Sound waters and shellfish areas. HQW is broader (any water rated Excellent by NC DWR). Triggers local-government rule adoption (15A NCAC 02H .1006) for new development within affected basin. Independent of Water Supply Watershed but often overlapping.