Dawson Creek RCMP says the woman, who is in her 30s, was seriously harmed in the assault — which is thought to have taken place in a field off 17th Street, between 116th Avenue and the Dangerous Goods Route in Dawson Creek.
The woman was taken to hospital, and is working with police.
Police located some of her personal belongings along the Dangerous Goods Route, where it approaches Highway 97 South.
Officers found fresh ATV tracks in the area and would like to speak to the rider, who may have information about the incident.
Police are also asking anyone who might have witnessed any people or vehicles in the area between midnight and 4:20 a.m. PT on Friday to contact police.