Smoke Testing

Smoke testing is part of the City's ongoing program to improve the sewer collection system by reducing unwanted water inflow and infiltration. Inflow occurs when storm drainage is improperly piped into the sewer. Infiltration occurs when cracks or other defects in the sewer mains allow groundwater to enter. Unwanted storm drainage and groundwater inflow to the sewer increases risk of sewage overflows and unnecessarily increases the volume of wastewater treated at the Treatment Plant, ultimately increasing ratepayer costs.

The smoke testing program will use an air blower and smoke to fill the sewer mains with non-toxic, non-odorous or staining smoke. Technicians will observe and document where smoke escapes from stormwater catch basins, rain gutters, or below-grade pipe defects, indicating inflow sources.