The Philadelphia School District is bracing for a possible SEPTA strike, warning parents and staff that city schools may need to shift to online learning if the city’s buses, subways, and trolleys grind to a halt Nov. 1.

In a letter to parents, Superintendent William R. Hite Jr. said that a SEPTA strike “would have a devastating impact on the operation of our School District and our ability to sustain in-person learning five days a week for all students — something we all worked extremely hard to make happen for all students this school year.”

A strike is not guaranteed; members of the Transport Workers Union Local 234 would have to vote to authorize a strike if no deal is reached by Oct. 31, when the current pact expires. The union is expected to soon schedule a strike authorization vote.

Nearly 60,000 city students rely on SEPTA to get to their schools; many of the district’s 20,000 employees also use public transportation. The district on Tuesday began asking staff to complete a survey about their transit usage, saying responses would help “inform our options” if a strike is called.

“In the midst of increasing gun violence and the many other traumas impacting our communities as the COVID-19 pandemic continues, our schools are a safe haven for thousands of Philadelphia’s young people,” Hite wrote in the letter. “We are advocating relentlessly with the city leaders for a non-strike resolution to SEPTA negotiations.”

» READ MORE: SEPTA workers vote to authorize a strike

In-person learning would be ideal, the superintendent wrote, but “staffing challenges or other conditions that may result from a strike could require some or all of our schools to shift to 100% virtual learning. Should the need arise, we will explore all feasible options based on the results of the survey, with the goal of continuing in-person learning safely for as many students as possible.”

The district has begun making contingency plans, Hite said, and is “committed to maintaining vital supports for our students such as grab-n-go meals.”

» READ MORE: SEPTA workers might strike soon. It wouldn’t be the first time.

When SEPTA workers last went on strike, in 2016, schools remained open. But since then, the district has equipped every student with a computer and virtual learning became a possibility. Most children learned remotely for the entire 2020-21 school year.

Hite urged families whose children have a Chromebook needing repair to reach out to their child’s school for a replacement or tech support.

Staff writer Thomas Fitzgerald contributed to this article.