Police say a man was driving a horse-carrying truck near Cootamundra when a magpie flew into the open window and hit the driver in the head.

As a result, he lost control of the vehicle and was taken to Wagga Base Hospital for treatment for minor injuries.

Riverina Highway Patrol Acting Inspector Ben Smith said the accident was one of three to cause minor injuries over the long weekend's traffic patrols for Operation Slow Down.

"There were positives and negatives to come from the weekend," he said.

"In a positive, we didn't have any serious or fatal collisions on our roads, which is great, but disappointingly, we had three minor injury collisions where three people were taken to hospital to be treated."

A second incident occurred in Wagga over the weekend where a woman rolled her vehicle.

"We will alleged the woman admitted to police that she had been using illicit drugs and alcohol, and she was conveyed to Wagga Base Hospital where blood has been taken and will be analysed," Acting Inspector Smith said.

The third incident was a result of inattention on the road, according to Acting Inspector Smith, who said a driver in Junee failed to stop where needed at a Give Way sign.