WEST BATH — A tractor-trailer jackknifed on Route 1 in West Bath on Wednesday afternoon, closing the busy highway to traffic and threatening a nearby river with leaked diesel fuel.

No one was injured in the incident but the driver was taken to Mid Coast Hospital as a precaution, police said.

The saddle tank on the truck ruptured when it hit the right guardrail on Route 1 during the crash.

There were no other vehicles involved.

The tank can hold up to 100 gallons of diesel fuel, and it had begun to spill into the New Meadows River. Brunswick and West Bath fire departments set up dikes to prevent diesel from leaking into the river.

“That’s a lot of diesel to spill in the pouring rain near a river,” Lt. Brian Quinn of the Sagadahoc Sheriff’s Department said. “EPA doesn’t like that very much.”

The state Department of Environmental Protection arrived at the site around 2:30 p.m. to assess the spill.

Northbound Route 1 traffic was being rerouted from Cook’s Corner in Brunswick onto Old Bath Road.