Metro Vancouver has dropped its air quality advisory issued Sunday for the eastern portions of the region and the Fraser Valley.
The caution against outdoor exertion, especially for those with respiratory problems, was in response to high readings of ground-level ozone that have since moderated.
The advisory was ended Tuesday evening.
Metro officials said slightly cooler temperatures have helped improve air quality.
That trend is expected to continue – Environment Canada has forecast cooler temperatures turning to rain by Friday.
Haze still hung over much of the region as of Wednesday morning.
Despite the end of the advisory, the B.C. Air Quality Health Index still predicted a moderate health risk level of 4.0 (on a scale of 1-10) today in northeastern Metro and the eastern Fraser Valley, declining to a lower risk level of 3 tomorrow.
The air quality health index readings peaked at 5.1 in the eastern Fraser Valley on Sunday, 5.0 in the central Fraser Valley, 4.9 in northeastern Metro and 4.2 in southeastern Metro.
High air quality index readings of around 7.0 are occurring in Williams Lake, Quesnel and Prince George, where residents are being affected by Interior forest fires.
For detailed air quality readings, forecasts and graphs of recent readings, see bcairquality.ca.
Ground-level ozone, or smog, forms when nitrogen oxides and volatile organic compounds react in sunlight.
The Fraser Valley Regional District issued a news release predicting Metro’s plans to build a a new garbage incinerator will further increase air pollution levels in the years ahead.
FVRD board chair Sharon Gaetz said the regional district is very concerned pollution from a new incinerator will further affect elderly and vulnerable Valley residents who often can’t go outside due to poor air quality.
“We hope that Metro Vancouver will finally acknowledge the pressure they will be putting on all British Columbians if they build another incinerator,” Gaetz said. “It would be ludicrous to consider building more facilities that will further harm our communities.”
Metro has argued the waste-to-energy project would have no significant net effect on air quality, because the energy generated can offset the burning of other fuels, as well as advanced emission scrubbing technology.
One of the proponents, a Delta cement plant, wants to burn the processed garbage as fuel and thereby reduce its current use of coal.
The project is not certain to be built in Metro either – a final site could be on Vancouver Island or near Squamish instead.
Air quality readings and forecast as of Wednesday morning: