Sewer Vapour Testing on Empire Avenue Next Week

Friday, October 14, 2022 - 8:45 AM
Image of manhole with non-toxic water vapour

On October 18 to 22, the City of St. John’s will be conducting sewer vapour testing on Empire Avenue and surrounding areas.

Testing is required to identify areas of the sewer system that needs updating. Work is scheduled along Empire Avenue and adjacent streets from Columbus Drive to Water Street. See project area map.

Consultant RV Anderson and Biomaxx Environmental will be conducting testing for the City of St. John’s. A large fan is placed over manholes in the street to blow artificially produced, non-toxic water vapour into the sewer system. Crews then walk the street and onto properties and use aerial drones to record locations where vapour is observed exiting the system.

Water vapour is not harmful to humans, pets, or plants, and will not stain clothing, drapes, or furniture. It may make you cough, as any vapour can be an irritant. If vapour enters into your home, exit your home immediately and notify the testing crew in the area, or contact Access St. John’s at 311 or 754-CITY (2489) or email

The vapour should not enter your home unless there is a deficiency within the plumbing system of your residence. If the vapour enters your home, it could be the result of:

  • damaged, or improper plumbing
  • infrequently used drains that have dried out over time
  • uncapped pipping rough-ins 

There will not be any service interruptions as a result of the vapour test. For more details about the work, please read the FAQ on