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As more people work from home and social distance in an effort to curb the spread of the coronavirus, several major metropolitan areas have seen a decline in emissions linked to cars and trucks and an improvement in air quality overall.

But because March is already one of the state’s best months for air quality, there’s no data to suggest these measures have made much of a difference in Utah, according to Jared Mendenhall, Department of Environmental Quality spokesman.

“If this were happening in December,” in the thick of the state’s inversion months, “you’d probably see something that was different,” he told The Salt Lake Tribune on Tuesday.

Utah’s capital city has among the worst air quality in the nation, with a recent analysis of large metro areas ranking Salt Lake City as No. 7 among the most polluted areas in the country. That dirty air is associated with a host of health risks, including an increased likelihood of heart attack among some populations and a higher risk of death among the elderly.

While the state is enjoying a steady string of green air days, experts say the broad social shifts implemented in response to the coronavirus could have a positive impact on pollution in the long run — even after the risk of contracting the illness is gone.

Thom Carter, executive director of the Utah Clean Air Partnership, said the coronavirus outbreak has forced some businesses that were otherwise resistant to teleworking to give it a try. And that means that on the next red air day, those companies will have the systems necessary to direct their employees to stay home.

“They can say, ‘OK, look, we’ve held 30- to 100-person Zoom meetings [during the coronavirus outbreak] — moving our board meetings to Zoom conference calls during December, January or February is not going to be a problem,’” he said. “Having everybody invest in infrastructure now will allow people to change their behaviors, be aggressive come winter.”

After teleworking for weeks, maybe even for months, during the virus scare, a few days here and there to help improve the air may seem much easier in the future, he added.

The coronavirus may also prompt Utahns to make changes on an individual level, said Mendenhall, with the DEQ.

“The thing we hope is people take this opportunity to evaluate how often they are using their automobiles and start to recognize there are some possibilities,” he said. “They don’t need to go to the grocery store every day and can do things that limit how they use their automobiles in the future.”

Data from the Utah Department of Transportation shows that traffic along the Wasatch Front has decreased by at least a fourth over the past eight days compared to typical weekdays before the coronavirus outbreak, John Gleason, a spokesman for the agency, said Tuesday.

UDOT set up 15 checkpoints, mostly on freeways, to count cars along the Wasatch Front to measure how coronavirus closures are affecting congestion.

“In general terms, what we’re seeing right now is about a 25% to 30% decrease in traffic,” Gleason said. “There was one particular point during the weekend — on Saturday — when it was down by 40%.”

That suggests that people are not only changing their typical weekday commute but are also making fewer social trips as they attempt to “flatten the curve” by social distancing to reduce the impact of the virus on the state’s health care systems.

While a New York Times analysis of satellite data found the response to the coronavirus had led to major declines in pollution over major metropolitan areas — including Los Angeles, Seattle, New York, Chicago and Atlanta — several experts said they expected air pollution to return to pre-coronavirus levels once the outbreak subsides.

Carter said it’s possible that once the coronavirus restrictions are lifted, Utahns will return to living their day-to-day lives much as they were before. Humans are, after all, “social people," he said, “and I think they’re craving interaction.”

But Carter said he’s still optimistic that when the dust from the coronavirus settles, new air quality solutions will emerge from the social changes people implemented to fight the spread of the virus.

“We hope there will be some space between when the restrictions are lifted and when we get back into an air quality emergency,” he said. “And so that will allow us to assess and reevaluate and put people in a quality position to make some changes.”

Tribune reporter Lee Davidson contributed to this report.