The biggest transportation agency in the South County in terms of ridership isn’t Regional Transit or the Altamont Corridor Express. It’s the Manteca Unified School District.

Every school day its fleet of 72 buses transports an average of 1,430 students from home to school.

Last year, district busses traveled 1,325,424 miles. That’s the equivalent of going to the moon (238,857 miles) and back 2.7 times every year.

Eight years ago the number of students transported was significantly higher for the 23,000-student school district. That was before state budget cuts prompted the district to increase the minimum distance for providing bus transportation between a student’s residence and their school campus.

Walking distance from home to school is now 1.25 miles for kindergarten through eighth graders and 2.5 miles for high school.

Parents can request an exemption to the rule and have their child picked up providing certain criteria are met: If a bus route goes in that direction and it doesn’t add time to the run.

Manteca Unified is currently transporting 52 students that qualified for a walking exemption.

“They typically involve safety issues on busy streets where it may be too dangerous to walk,” noted Superintendent Jason Messer. “There are some locations as an example, within the walking distance that we transport because students live along high-speed French Camp Road.”

The district expanded their bus fleet in the middle of the Great Recession to save money. They added short buses to provide transportation for special needs students instead of contracting the service out to First Student. The transport costs for special needs students have been slashed by upwards of $1,000 a year down to $11,000 per student. It costs $3,788 to transport other students for a year with the cost difference mainly in larger busses that aren’t designed for wheelchair access. The district also contracts with First Student to transport students to county-run special education schools. There are 2,800 special education students in Manteca Unified.

There are 27 special needs routes, 18 regular education bus routes and two field trip buses built into the daily schedule. In addition, there are four McKinley-Vento routes — legislated for homeless students — that are driven to school in a district van. That allows students, regardless of how often their families are forced to move around to keep a roof over their heads, to still be able to get to school. In some cases students are picked up in Stockton so they can finish the school year in Manteca Unified if their families are forced to relocate there. The rationale behind the state law is to minimize the education disruption of kids caught in a chaotic and uncertain living situation.

During the 2013-14 school year, there were 858 activity trips for sports and other organized activities and event excursions that resulted in extra work for drivers.

Messer noted the district’s vehicle mechanical staff that also looks after other district cars and trucks besides busses routinely get high marks from California Highway Patrol motor carrier officers during mandatory and random bus inspections.

The district also does an inspection of its own either every 45 days or 3,000 miles — whichever comes first — on each bus.

Bus drivers receive a minimum of 10 hours of training annually.

Manteca Unified was among the first districts in the Central Valley to equip busses with flashers to make them more visible in fog.