An illicit discharge is the disposal of anything other than rainwater or snowmelt into the pipes, ditches, or streams that make up the stormwater system. Illicit discharges can be direct or indirect, possibly including anything on the ground that could reach the stormwater conveyance system. These pollutants are often harmful to stream water quality or ecology.
Allowable discharges that do not significantly impact water quality or cause or contribute to a violation of applicable water quality standards and are discharged in accordance with the best management practices (BMPs) in the Town’s Design Manual include:*
Water line flushing;
Diverted stream flows;
Uncontaminated groundwater infiltration;
Uncontaminated pumped groundwater;
Discharges from uncontaminated potable water sources;
Foundation or footing drains;
Air conditioning condensation (commercial/residential only);
Water from crawl space pumps;
Individual residential car washing;
Flows from stream habitats and wetlands;
Discharge of street wash waters;
Discharges from dechlorinated swimming pools. These discharges do not include pool filter backwash discharge or saltwater pool discharge, which are prohibited.
Discharges associated with emergency removal and treatment activities for hazardous materials if authorized by the federal, state or local government on-scene coordinator.
Maintenance activities of the stormwater drainage system requiring flushing or cleaning with potable water.
Illicit discharge permitted under an NPDES permit, waiver, or waste discharge order issued to the discharger and administered under the authority of the USEPA, or NCDWR, provided that the discharger is in full compliance with all requirements of the permit, waiver, or order and other applicable laws and regulations.
Discharges specified in writing by the Town Manager as being necessary to protect public health and safety or discharges that have been filtered through an approved pretreatment system that consistently demonstrate no discharge of pollutants.
*If any of the above-listed exceptions to the discharge prohibition are found to be polluted and may therefore negatively impact the quality of the waters of the State, the polluted illicit discharge exception shall be deemed unlawful and shall not be discharged into the stormwater drainage system. These conditions shall be determined by the Town Manager. These discharges, though listed as an exception above, shall be regulated as an illicit connection or discharge.
What are examples of illicit discharges?
Pollutants may include, but are not limited to:
Paints, varnishes and solvents;
Gasoline and other petroleum fuels;
Oil and other automotive fluids;
Food waste, including cooking oil and grease;
Non-hazardous liquids, solid wastes, and yard wastes;
Pool filter backwash;
Refuse, rubbish, garbage, litter, or other discarded or abandoned objects;
Insecticides, fungicides, herbicides, and other pesticides;
Soot, slag, and ash;
Hazardous substances and wastes;
Sewage, animal wastes, fecal coliform, Escheria coli, and pathogens;
Dissolved and particulate metals;
Wastes and residues that result from constructing a building or structure (including, but not limited to, sediments, slurries, and concrete rinsates);
Eroded soils, sediments, and particulate matter; and
1. Who do I call if I see mud or sediment coming off of a construction site?
For sites that disturb 20,000 square feet or more, contact Orange County Erosion Control at 919-245-2580. How big is 20,000 square feet? Picture half a football field without the end zones. Common examples include subdivisions, large apartment buildings, and large commercial or institutional projects.
If the site disturbs less than 20,000 square feet, call Chapel Hill Stormwater at 919-969-RAIN (7246). Most residential lots are less than 20,000 square feet.
Not sure who to call? Contact Chapel Hill Stormwater at 919-969-RAIN (7246).
You can also download the Muddy Water Watch app, which helps monitor and report erosion control issues. Partnering with county Sediment and Erosion Control programs, Haw River Assembly provides training, materials, and the tools necessary for volunteers to properly identify and report sediment and erosion control violations.
2. What are other types of water pollution issues at construction sites that I should report?
Possible construction site water pollution issues include:
Water has a sheen that could be from oil, grease, or paint solvents;
Trash and other debris from the site has drifted off-site;
A lot of algae is growing in nearby waters;
Oil or mud is tracked out into the street; and/or
Nearby waters are murky or cloudy.
If you notice any of these issues:
Do not enter the construction site.
Contact the NC Department of Energy, Mineral, and Land Resources (DEMLR) at 919-707-3639. They are responsible for regulating construction stormwater permits.
Call Chapel Hill Stormwater at 919-969-RAIN(7246) so local staff can follow-up on the issue.