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Stormwater Management
Illicit Discharge Detection and Elimination

Every year the City is charged with the task of detecting and eliminating any illicit discharges into the storm sewer system. An illicit discharge is the discharge of pollutants or non-storm water materials to storm water drainage systems via overland flow or direct discharge of materials into a storm drain. Only rain belongs down the drain! Illicit discharges can vary from the direct connection of a laundry machine into the storm sewer system to the blowing of grass clippings into a storm sewer inlet.

To help combat illicit discharges, the City performs "Dry Weather Screening" during the spring and summer months. The screening consists of randomly selecting 75 storm drainage structures. Once selected, technicians check these sites for flow. If detected, flows are sampled and tested for both quantitative and qualitative data.


Quantitative Data: Qualitative Data:
Chlorine concentration Odor
Copper concentration Oil sheen
Concentration of detergents Surface Scum
Phenol concentration Color
pH level Turbidity
Flow rate Surrounding vegetation
Temperature Condition of the structure


Following the initial detection and testing of flow, sites are rescreened the following day to confirm the first day's results. If any of these tests display results outside of standard operating parameters, then a sample is collected and sent to the Hampton Roads Sanitation District for more testing by a certified lab to confirm the in-field data. In total, the technician's main goal is to identify the source flow and address the problem accordingly. Residents are often our biggest eyes and ears so if you see an illicit discharge, report it at 393-8666.

Normal operating hours are M-F, 7:30am-4:00pm. To report an illicit discharge after hours, please contact the Department of Environmental Quality (http://www.deq.state.va.us/) 24 hour hotline at 1-800-522-0206.


City of Portsmouth, Virginia · All Rights Reserved · Portsmouth City Hall · 801 Crawford Street · Portsmouth, VA 23704 · 757-393-8000