Updated 4:45 p.m. Aug. 18: Officials have declared another Spare the Air Day for Sunday, Aug. 19 — the 19th such declaration in the region this year. Unitrans will waive all fares Sunday, but the transit system's practice of providing free rides on Spare the Air days will come to an end Monday, Aug. 27. Complete information in the article below.

•••

A Spare the Air declaration for Saturday (Aug. 18) means Unitrans will once again waive its fares as a way to encourage people to leave their cars at home. The fare waiver will be the last or one of the last ones of the year, as the UC Davis and city of Davis transit system has announced that it will end the program Aug. 27.

“With the high number of wildfires this year, Davis and the surrounding area have experienced an unprecedented number of Spare the Air days, more than Unitrans anticipated in its annual budget,” said Jeff Flynn, general manager of Unitrans, which is operated by the Associated Students of UC Davis.

Unitrans is one of the last transit systems in the region to provide free rides on Spare the Air days, which are declared when the Air Quality Index hits 126 in the range of “unhealthy for sensitive groups.” This year has seen Spare the Air days: June 13 and July 18; July 27-Aug. 10 (15 days in a row); and Aug. 18 — that’s 18 total, one more than the last two years combined.

“The program, though, has not resulted in higher transit usage,” Flynn said. Nevertheless, he said, Unitrans will bring back free Spare-the-Air rides for a limited amount of days in 2019 with the hope that more people will take advantage.

“With fewer cars on the road, we’ll have a lessening of greenhouse gas emissions,” he said. “Not only that, but most of our buses run on natural gas, which burns cleaner than diesel.”

Follow Dateline UC Davis on Twitter.