The bus was traveling down Whiskey Bottom Road at Northgate Road when police say it left the roadway and hit a mailbox and a water runoff drain. No one was seriously hurt.
The bus carrying 44 students from Forest Ridge Elementary School when the accident happened.
Police were called to the scene and the driver, 33-year-old Stacy Jean McKinney of Laurel, Md. was arrested. She faces multiple charges including driving while impaired, drug possession, and negligent driving.
A Howard County Schools spokesperson told FOX 5 the driver of the bus has been suspended from transporting students pending the outcome of the police investigation. A new driver was assigned to the route.
The school system doesn't operate its own fleet of buses, instead outsourcing its bus service through private contractors in and around Howard County.
Court documents say McKinney told police she wasn't able to stop the bus because the brakes failed.