WILMINGTON, Del. — A school district here is reorganizing its bus routes and shifting start times for the 2018-19 school year to address the most severe shortage of bus drivers it has ever experienced.

The Red Clay Consolidated School District will move to a three-tier school schedule in the fall, according to an announcement on the district’s website. The new system will reduce the number of drivers needed to cover routes because high school and middle school students will no longer need to be picked up at the same time.

The district is shifting the start time for the high school instructional day about five to 10 minutes earlier, to 7:25 a.m. It is also moving the start times for the middle school instructional day 30 minutes later, to 8:05 a.m., and is pushing back the elementary school instructional day by 10 minutes, to 9 a.m.

Although the school start time for high school students will be earlier than last year, the school bus pickup times will remain the same, the district notes on its website.

Minimal adjustments will be needed for transportation to and from athletic and other extracurricular activities.

The district analyzed its bus routes last year and determined that moving to a three-tier schedule was the most viable solution, since other school districts in the area have already seen success in running three-tier schedules, a three-tier system frees up drivers to cover vacant routes, and the plan frees up bus aides, allowing them to be assigned to other routes. Additionally, the change will reduce the amount of time many students spend on the bus, according to the district’s website.

The district is dealing with the most severe shortage it has ever encountered, its website said.

“Our transportation department worked very hard this past year to try and provide reliable bus service while facing the worst driver shortage in history,” said Merv Daugherty, the district’s superintendent. “Unfortunately, we don’t believe those efforts solved the problem. We are not happy with the status quo, so we are making some needed adjustments in school start times. The center of this plan will be the outstanding men and women driving our buses every day.”

The Delaware News Journal reports that the district had merged several bus routes for the 2017-18 school year, which put school buses closer to maximum capacity. It had also introduced an app that allows parents to track their child’s school bus and can help with route planning. However, some parents said the arrival times aren’t accurate, which exacerbated "the issue that buses were frequently late.”

Earlier this year, Kelly Shahan, the transportation director for Red Clay Consolidated School District, told the newspaper that there is a national school bus driver shortage, and that the district has been contending with driver shortages for years, in part due to low pay, the fact that drivers go through a lot of screening, and that it is a tough job. Drivers interviewed by the Delaware News Journal said that in addition to pay, other factors contributing to the shortage are safety and behavior management issues.

The district will share more details on the changes over the summer.