A special air quality statement is still in effect for Vernon Friday, March 12, due to dust and high concentrations of coarse particulate matter that is stirred up by traffic.
But, advisories, like the one first issued March 9, is not unusual in Vernon.
Air quality advisories have been issued at least three times since the snow started to melt in February.
A dust advisory issued March 3 saw particulate matter concentrations (PM10) reach 85.8 in Vernon by Friday, March 5, compared to Kelowna’s 45.4. The provincial air quality objective for PM10 is 50 micrograms per cubic metre averaged over 24 hours.
The city’s road manager Chris Ovens offered an update on March 8 on how the department is keeping up with dust control.
Ovens provided a full report to council this time last year (March 23, 2020) that found aggregate compared to sister cities is similar “if not better.”
Since that update, Ovens said continuous work with a geotechnical engineer resulted in the launch of a new aggregate product that was used through winter.
The city focused on measurements below 0.6 millimetres as particulate matter smaller than this likely related to dust complaints, according to a ministry report.
“If you’re to imagine a sieve you would, as a kid, use on the beach, it would have that opening (0.6mm),” Ovens said. “Previously, we had 26 per cent of the product pass through.”
“We dropped that down to 9.5 per cent.”
The old product had 10.9 per cent pass through 0.3mm, that’s been halved to 5.2 per cent, Ovens said.
“It’s continually getting smaller,” he said. “This product was used all winter. Unfortunately, not a huge winter that we’re used to having, but it was out there.”
Improved aggregate that is more in line with ministry standards will work to alleviate dust, he explained.
The department also took advantage of “value-added opportunities” and will deploy six additional air-quality sensors around the city providing live-time data tracking PM10 measurements providing “comparative data with what the city is experiencing as a whole,” Ovens said.
Ovens also put in a request to have the provincial air-quality sensor outside the Okanagan Science Centre, along Highway 6, relocated. Word has returned from the province that a secondary temporary monitoring site is being looked at as a possibility.
“We understand the effects (dust) has on residents, so we’ve committed to providing that sweeping focus so we do focus on the highway as soon as possible,” Ovens said. “But, we’re also under the governance of weather.”