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Stormwater Management
For questions related to Orange County's Stormwater Management Program please call (919) 245-2575
TO FILE AN INQUIRY OR COMPLAINT RELATED TO STORMWATER - CLICK HERE
Stormwater Management Plan
Section 6.14: “Stormwater Management” of the Orange County Unified Development Ordinance (UDO) states that a Stormwater Management Plan must also be submitted for any new development or land-disturbing activity exceeding the thresholds noted in the Watershed Matrix Table. The requirements apply to all new development within the Orange County planning jurisdiction, including private, public, state, and federal development not covered by a separate NPDES permit.
Stormwater Management Plans must address the following:
- Protection of riparian areas;
- Nitrogen and phosphorus load contributions;
- Peak flow attenuation for the 1-year, 24-hour storm;
- Control and treatment of runoff generated by one inch of rainfall from all project area surfaces;
- Engineered Primary and Secondary Stormwater Control Measures (SCMs) as outlined in the NC Department of Environmental Quality Minimum Design Criteria (MDC) Manual
Note: Regulation of any standards for the removal of nutrient exports within the Jordan Lake Watershed are currently under review and have been delayed. Currently, Orange County only has the regulatory authority to regulate stormwater quantity within this watershed.
- Neuse Buffer Rules
- Non-Neuse Buffers
- Surface Water Identification
- Stormwater Pollution / Illicit Discharges
- Open Burning
Neuse Buffer Rules
The State of North Carolina has designated Orange County as the delegated authority to administer the Neuse Buffer Rules within Orange County's Neuse River Basin, outside the Town of Hillsborough and it surrounding Extra Territorial Jurisdiction (ETJ). Located in the northeast portion of the County, the Neuse River Basin is comprised of the:
- Flat River
- Little River
- Lower Eno protected watersheds
- Lower Eno unprotected
- Upper Eno Critical Area
- Upper Eno
Neuse buffered streams have a 50 feet riparian buffer, however under the Orange County Unified Development Ordinance, these watersheds also have more restrictive County stream buffer requirements. See the Orange County Unified Development Ordinance for additional information.
Non-Neuse Buffers
The non-Neuse River Basins include the Roanoke Basin in the extreme northwest portion of the County (approximately 10 square miles comprised of the Hyco Creek and South Hyco Creek watersheds) and the Cape Fear Basin in the western and southern portions of the County, comprised of the:
- Back Creek
- Cane Creek Critical Area
- Cane Creek
- Haw Creek
- Haw River protected
- Haw River unprotected
- Jordan Lake protected
- Jordan Lake unprotected
- University Lake Critical Area
- University Lake watersheds
See the Orange County Unified Development Ordinance for specific watershed stream buffer requirements.
Surface Water (Stream) Identification
The presence of a stream buffer can affect proposed land use such as driveways and building locations. The county has, in the Planning Department, a base map of all known streams. Anyone who wishes to dispute the map may request staff to "field" or "ground" truth the stream. Staff will use methodologies and criteria developed by the North Carolina Division of Water Quality to determine if the stream feature shown on the map is indeed subject to buffer requirements.
Additional Information
Stormwater Pollution
So why do we care about stormwater? Quite simply North Carolina’s number one water quality problem is stormwater runoff pollution. As stormwater flows across impervious (i.e. paved) surfaces or exposed soil, it picks up various pollutants, such as oil and grease, excess nutrients, bacteria and sediment. Polluted stormwater flows down our storm drains and ditches where it is discharged, untreated, into our streams, rivers, and lakes. Stormwater runoff pollution causes adverse impacts to aquatic ecosystems, poses human health risks, and can greatly increase the cost of treating our drinking water. For more information about stormwater pollution and stormwater resources contact by phone at 919-245-2575.
Illicit Discharge Detection and Elimination (IDDE) Program
Orange County does not own, operate, or maintain any public stormwater collection/treatment systems. Almost all of the public stormwater systems that you see in Orange County are owned, operated, and maintained by the North Carolina Department of Transportation (NCDOT) or local municipalities (e.g. Town of Hillsborough, Town of Chapel Hill, Town of Carrboro, City of Mebane, City of Durham, etc.). Orange County does own, operate, and maintain site-specific stormwater collection/treatment systems that are located on Orange County government-owned properties; however, the majority of those site-specific systems fall under the stormwater management jurisdiction of local municipalities.
The Orange County Erosion Control / Stormwater Division monitors all non-incorporated areas of Orange County (i.e. areas located outside of NCDOT/Town/City jurisdictional limits) for illicit discharges to local stormwater collection/treatment systems and local watersheds. An illicit discharge is defined as any discharge, dumping, or spill that is not composed entirely of stormwater, except for allowable non-stormwater discharges and discharges resulting from firefighting activities.
Orange County implements an Illicit Discharge Detection and Elimination (IDDE) Program for non-incorporated areas located within Orange County, as detailed within Section 6.14.12 of the Orange County Unified Development Ordinance (UDO). The UDO states that no person shall discharge or cause to be discharged into the stormwater collection system or receiving waters any materials, including but not limited to pollutants or waters containing any pollutants that cause or contribute to a violation of applicable water quality standards, other than stormwater.
The information shown below is applicable to all new development and existing projects within Orange County’s planning jurisdiction:
Allowable Non-Stormwater Discharges:
- Waterline flushing,
- Landscape irrigation,
- Diverted stream flows,
- Uncontaminated rising groundwater,
- Uncontaminated groundwater infiltration to the stormwater collection system,
- Uncontaminated pumped groundwater,
- Discharges from potable water sources,
- Foundation drains,
- Uncontaminated air conditioning condensation,
- Irrigation water,
- Springs,
- Water from crawl space pumps,
- Footing drains,
- Lawn watering,
- Non-commercial car washing,
- Flows from riparian habitats and wetlands,
- NPDES permitted discharges,
- Street wash water,
- Fire fighting emergency activities,
- Wash water from the cleaning of buildings,
- Dechlorinated backwash and draining associated with swimming pools,
- Flows from firefighting,
- Discharges specified in writing by the County as being necessary to public health and safety,
- Dye testing is an allowable discharge, but requires verbal notification to the Erosion Control Officer prior to the time of the test, and
- Any non-stormwater discharge permitted under an NPDES permit, waiver, or waste discharge order issued to the discharger and administered under the authority of the Federal Environmental Protection Agency, provided that the discharger is in full compliance with all requirements of the permit, waiver, or waste discharge order and other applicable laws and regulations, and provided that written approval has been granted for any discharge to the stormwater collection system.
Prohibited Discharges
It is a violation of the UDO for any person to discharge any substance into the stormwater collection system or receiving waters which by its nature, may:
- Become a public health hazard endangering human or animal health.
- Interfere with the free and rapid flow of surface water,
- Be flammable or explosive,
- Be toxic to human, animal or plant life,
- Be corrosive or damaging to the stormwater collection system, or
- Affect adversely the State of North Carolina classification of the stream into which the discharge flows.
- Non-allowable discharges include, but are not limited to, the following
- Dumping of oil, anti-freeze, chemicals, garbage, paint or cleaning fluids,
- Untreated animal waste,
- Commercial car washes,
- Industrial discharges,
- Contaminated foundation drains,
- Cooling water unless no chemicals are added, and a NPDES permit is in place,
- Washwaters from commercial and industrial activities,
- Sanitary sewer discharges,
- Septic tank discharges,
- Washing machine discharges, and
- Chlorinated backwash and draining associated with swimming pools.
Illegal Connections to Stormwater Collection Systems
- The construction, use, maintenance, or continued existence of illegal connections to the stormwater collection system is prohibited
- Any connection to the stormwater collection system which allows the discharge of non-stormwater, other than the exclusions listed in Section 6.14.12(C) of the UDO, is prohibited.
- The prohibition of illegal connections expressly includes, without limitation, illegal connections made in the past, regardless of whether the connection was permissible under law or practices applicable or prevailing at the time of the connection.
- A person is considered to be in violation of the UDO if the person connects a line conveying sewage to the stormwater collection system, or allows such a collection to continue.
- Grace Periods
- Where such connections exist in violation of the UDO, the property owner, or person using said connection shall be required to remove the connection within one year following the notice of violation. This grace period shall not apply to connections which may result in the discharge of hazardous materials or other discharges which pose an immediate threat to health and safety, or are likely to result in immediate injury and harm to human, animal or plant life, and natural resources.
- Where it is determined that the one year grace period shall not apply, the Erosion Control Officer shall determine the time within which the connection shall be removed. In setting the time limit for compliance, the Erosion Control Officer shall take into consideration the following:
- The quantity and complexity of the work.
- The consequences of delay.
- The potential harm to the environment, to the public health, to public and private property, to wildlife, and to natural resources.
- The cost of remedying the damage.
Spills
Spills or leaks of polluting substances discharged to, or having the potential to reach the stormwater collection system or receiving waters, shall be contained, controlled, collected, and removed promptly. All affected areas shall be restored to their preexisting condition.
- Notification of Spills
- Notwithstanding other requirements of law, as soon as any person responsible for a facility or operation, or responsible for emergency response for a facility or operation (the Financially Responsible Person) has information of any known or suspected release of materials which are resulting or may result in illegal discharges or pollutants discharging into or may reach the stormwater collection system or waters of Orange County, the Financially Responsible Person shall take all necessary steps to ensure the discovery, containment, and cleanup of such discharge.
- In the event of such a discharge of hazardous materials, the Financially Responsible Person shall immediately notify emergency response agencies of the occurrence via emergency dispatch services, and shall notify the Erosion Control Officer within 24 hours.
- In the event of a discharge of non- hazardous materials, the Financially Responsible Person shall notify the Erosion Control Officer no later than the next business day.
- All notifications shall be confirmed by written notice addressed and mailed to the County within three business days of the discharge.
- Notification shall not relieve the Financially Responsible Person of:
- Any liability or expense related to the discharge.
- Restoration of any area affected by the discharge to preexisting conditions.
- Liability or violation of any regulatory body of the County, State or Federal government.
Additional Information
Development Related Burning Information: Open Burning Prohibited
Effective September 16, 2003 Per Orange County Unified Development Ordinance. Open burning of trees, limbs, stumps, and construction debris is prohibited in Orange County for all activities associated with the development of a subdivision and/or any other permitted land-disturbing activities. This does not include activities involving the production and management of agricultural or forestry products.
View the Non-Development related Burning Permits and Requirements website.
- April 2020 Neuse Nutrient Strategy
- Memorandum of Understanding For Clean Water Education Partnership (CWEP) Services Provided by the Triangle J Council of Governments
- CWEP Introduction to Stormwater Runoff Video
- 2012 Stormwater Requirements (PDF)
- Stormwater Management Plan Review Fee
- Current Nutrient Offset Fees
- Stormwater Management Programs as outlined in the Unified Development Ordinance
- Rain Gardens for Orange County (PDF)
- Stormwater Best Management Practices Manual - Division of Water Resources (DWR)