NPDES is a federal Environmental Protection Agency (EPA) program. Its goal is to reduce pollution in our waterways through the use of permits for facilities and municipalities/tribes/states that discharge effluent and/or stormwater into waterways. Although previously applied only to industrial and commercial dischargers and sewage-treatment operations, permits through the program are now also required for municipal stormwater, or non-point source, discharges. Water Permitting 101 explains the history of water quality legislation, NPDES and the use of permits.
EPA requires six minimum measures called Best Management Practices (BMPs) for NPDES Phase II permitting. Each of these management practices must have measurable goals defined to evaluate their effectiveness in the removal of pollutants from stormwater runoff:
1) Public education and outreach
2) Public involvement and participation
3) Illicit discharge detection and elimination (IDDE Ordinance)
4) Construction site stormwater runoff control: Orange County Erosion and Sedimentation Control performs all
permitting, inspection, and enforcement in Chapel Hill.
5) Ensuring post-construction stormwater management in new development and redevelopment
6) Pollution prevention/good housekeeping for municipal operations
NPDES - Phase I permitting was required in 1989 for North Carolina for: 1) large state facilities and municipalities with stormsewer systems; 2) eleven categories of industrial activity; and 3) construction activity that disturbs more than 5 acres of land. NPDES - Phase II permits, which went into effect in 2005, apply to medium and small municipalities with stormsewer systems, such as Chapel Hill's, and construction activities that disturb from 1 to 5 acres of land.
In North Carolina, the Department of Environmental Quality- Division of Energy, Mining and Land Resources (DEMLR) oversees NPDES permitting through its Stormwater Permitting Program.