The Iowa State Patrol investigated a tractor trailer accident on Interstate 35 south of Williams on Wednesday night. The accident happened at the northbound 139 mile marker at around 9:10 p.m.. Reportedly a 2005 Kenworth semi tractor trailer operated by Cory Studer of Corwith,Iowa was traveling northbound at the time when it ran off the road and went into the ditch colliding with a fence. The Studer semi then came to rest in the shrubs and field. Studer was transported to Van Diest Medical Center in Webster City by the Williams Ambulance for treatment of possible injuries. Damage to the semi was estimated at $20,000 with the damage to the fence and mile marker post estimated at $300. Iowa State Patrol trooper Dylan Hoelscher cited Cory Studer with Failure to Maintain Control.