If all goes well, Michelle Donia’s daughter arrives home in Westtown Township from Collegium Charter School in Exton around 5 p.m.

But on days the bus driver “forgets the route,” Donia said, her fourth grader has been late by a half-hour or more: “It’s hit or miss.”

Donia’s daughter is bused by the West Chester Area School District, which, like other Pennsylvania districts, transports charter and private school students in addition to those enrolled in its schools.

And along with districts across the country, it doesn’t have enough bus drivers.

Nationally, 24% of school districts reported “desperate” or “severe” driver shortages in a survey this year by School Bus Fleet, an industry trade publication. An additional 38% reported “moderate” shortages. The median pay for bus drivers in 2018 was $34,450, according to the U.S. Bureau of Labor Statistics — which predicts a “very good” job outlook, “as many drivers are expected to leave the occupation.”

Locally, whether they contract out for bus services — as most in Pennsylvania do — or manage their own fleets, school districts around Philadelphia are experiencing a driver shortage.

The situation has forced some districts like West Chester to rely on substitute drivers not familiar with routes, or to double up on runs, prolonging the amount of time kids sit on buses.

“That can be upsetting to the students. It can be upsetting to the parents,” said Joanne Yarnall, the West Chester transportation manager.

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She and others attributed the shortages to a strengthened economy that has presented potential drivers with other job options.

“Typically in this industry, if the economy is in the toilet, we have enough drivers,” said Yarnall, who has managed West Chester’s department for 19 years. “Part-time work is better than no work.”

Driving a school bus requires hours of training, background checks, a willingness to work a split shift — and an affinity for managing students.

“You’re looking for a specific kind of person,” said Mike Berk, executive director of the Pennsylvania School Bus Association, which represents companies that provide districts with busing services. About 85% of Pennsylvania districts contract for busing, according to Berk.

“It’s not as if you can take pretty much anybody off the street,” he said.

School Bus Fleet said the national shortage, which has been ongoing for years, appears to have lessened from 2018. In Pennsylvania, Berk’s association doesn’t collect data. Anecdotally, he said he thinks the situation has gotten “progressively worse.”

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The number of licensed school bus drivers in Pennsylvania has declined over several years — from 46,000 in 2013 to 44,000 last year.

In West Chester, “we’ve received more complaints this year than we have in the past,” Yarnall said. As of this week, she said, 12 of the district’s 192 routes didn’t have permanent drivers. On days the district is short, she said, it’s assigned some drivers a double route — meaning students whose typical ride home takes 20 minutes may be on the bus for 35 or 40.

In Bucks County, the Council Rock School District began the school year with a shortage of 16 drivers. In September, the district told parents that First Student, its bus contractor, was averaging nine callouts a day, leaving the district down 25 drivers for its 150 buses.

First Student is advertising school bus driver jobs in Pennsylvania and New Jersey with sign-on bonuses of $1,000.

The Krapf company, which contracts with a number of area districts primarily in Chester County — including West Chester — this year began paying drivers to go through training.

“It’s just competitive. I think that’s how you have to look at it,” said Shawn McGlinchey, who works for Krapf’s safety team. With an “acute shortage” of drivers, McGlinchey said, he and others in management have stepped in to drive buses as needed.

The shortage is also affecting plans to delay school start times to allow kids to get more sleep: In Lower Merion, district leaders have cited the difficulty in finding drivers as an impediment to certain schedule options.

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Some districts are thinking strategically about how to recruit more drivers. Unionville-Chadds Ford parked a bus outside its high school and middle school in July to advertise open positions.

“Strangely, it seems that’s what brought in the most eligible applicants for us,” said Marco Sordi, the district’s transportation supervisor. His department, which manages its own bus fleet and employs 64 drivers, was down six last October; this year, it was fully staffed.

Besides advertising, Sordi said the department this year added bonuses for new drivers: $300 after three months, $700 after a year, and $1,000 after two years. Starting pay is $18.50 an hour.

Sordi also tries to make sure drivers feel appreciated. “If one of my bus drivers goes above and beyond, I like to write a letter to my superintendent telling them what the driver did,” he said. He gives the driver a copy of the letter.

In New Jersey, the Burlington Township School District will host a job fair at its middle school next Saturday to hire substitute bus drivers. The district timed the event to coincide with a holiday craft show, hoping to attract people who might not have otherwise considered driving a bus, said spokesperson Liz Scott.

Burlington Township hasn’t had to double up its bus routes as much this year, but it still has to cope with a shortage — sending managers out to cover when needed, Scott said.

While some people like the split shift that comes with driving a school bus, “if you don’t live right down the street, it’s not exactly ideal,” Sordi said.

But he and others emphasized the positive aspects of being a driver. In West Chester, drivers can bring their children with them, Yarnall said.

A school bus driver of 23 years before taking over West Chester’s department, Yarnall said she tries to dispel myths about driving a school bus.

“It’s the negative in this industry that catches the news — an accident, the bus hits something,” Yarnall said.

“Most of our drivers, they enjoy driving a school bus," she said. "It’s fun to get to know the kids, to know their families, when you’re on the same route every year. I actually miss it.”