ESCANABA — Smoke testing is continuing today on sanitary sewer systems along Ludington Street in downtown Escanaba. Crews are hoping to find where storm and groundwater may be entering the city’s sewer system.

Water Wastewater Operator Rick Gascon says they have found areas that need to be addressed.

“Mostly roof vents and some roof drains and one storm that is allowing rain water in,” Gascon said.

The smoke itself is generated at a manhole in the middle of Ludington Street and pushed through the system.

“It’s a liquid smoke that’s odorless, non-toxic and it burns off on the exhaust manifold of the motor that has a blower on it and then blower pushes it into the sewer,” said Gascon.

Crews then walk around the buildings to see where the smoke might be escaping. Spotters from the top of a fire ladder truck check rooftops to see if they can identify drains connected to sewer rather than storm drains.

Testing started Wednesday. Gascon says it could continue into next week.