ROTHSAY, Minn. - One lane of westbound Interstate 94 near Rothsay remained closed at 9:40 a.m. today, more than seven hours after a semitrailer hauling bottled water overturned on the road.

The driver, Bill Fisher, 44, of Strafford, Mo., told authorities he fell asleep at the wheel and the truck entered the median. He tried to pull back onto the traffic lanes and the 2006 Peterbuilt semi rolled onto its side, sliding under the County Road 24 overpass and blocking both westbound lanes, the Minnesota State Patrol said.

Fisher wasn't injured in the accident, the patrol said.

Crews were working to unload the bottled water from the trailer. The Minnesota Department of Transportation put up signs warning motorists of the situation, and drivers are asked to slow down when going through the area.

The accident happened at about 2 a.m. at mile marker 39 just east of Rothsay. The Otter Tail County Sheriff's Office assisted at the scene.