It was just artificial smoke, but it led to a number of calls to the Langley Township Fire Department on Wednesday.
The Township’s engineering department was doing smoke testing of sanitary sewers in Aldergrove for several days leading up to Sept. 14.
The tests resulted in smoke coming up out of sewer grates or vents on houses, leading to the emergency calls.
Assistant fire chief Bruce Ferguson confirmed there had been a number of calls, particularly on Wednesday.
The testing is part of a regular program of sewer repair.
“It actually helps us to find if there’s any leaks into the sanitary [sewer] system,” said Wyatt Babcock, the utilities operation superintendent. “If smoke can get out, water can get in.”
If the smoke appears to be coming out of a house, it will be coming from a roof vent linked to the sewer system. It’s a sign that the house’s plumbing may have an issue where it hooks to the sewer, said Babcock.
The smoke may also come from grates where the storm drain system is leaking into the sewer system.
Finding and repairing leaks like those saves the Township money.
The smoke used is “Hollywood smoke.”
“It’s perfectly harmless,” said Babcock.
Large areas south of 33rd Avenue are being tested, with the testing expected to wrap up on Sept. 14.