FAIRHAVEN — A serious rollover crash on Route 195 Thursday afternoon led to a portion of the highway being closed down, and it likely will not reopen until sometime Friday.

Shortly after 3:30 p.m., Fairhaven Police and Fire Departments responded to a motor vehicle crash on Route 195, between the Alden Road and Adams Street overpass on the westbound side of the highway. The crash involved a pickup truck and a septic tank truck. The septic truck, owned by Flomaster of Middleboro, was carrying approximately 3,000 gallons of sewerage, which spilled onto the roadway.

Fairhaven paramedics transported the driver of the pickup truck to Rhode Island Hospital, and a Medflight helicopter transported the septic truck driver to Rhode Island Hospital. Both patients were listed in serious condition, and their names are being withheld at this time. Massachusetts State Police said both victims are expected to survive.

State Police are conducting an investigation into the cause of the crash.

Frank Corp. and the Massachusetts Department of Environmental Protection are conducting a cleanup of the septic waste spill. Traffic on the westbound side of Route 195 has been diverted and that portion of the roadway has been closed for the cleanup. The roadway is estimated to reopen sometime on Friday.