A man lay hurt for 17 hours before being found with serious abdominal and pelvic injuries after his quad bike fell on top of him near the edge of a river.

Nathan Cleverley, 40, was found just before 11am yesterday at the back of a farm in Matamata - but his ordeal began when he came off his quad bike at 6pm on Monday.

Farm owner Craig Garland, who found Mr Cleverley, said he was too injured to walk for help.

Mr Cleverley rents a sleepout at a neighbouring farm and is a casual worker there. Mr Garland saw him fishing on the bank of the Waihou River on the Old Te Aroha Rd property on Monday afternoon. When he was told yesterday that Mr Cleverley had not returned home that night he went to search for him.

"As soon as he heard my bike he knew someone was there and he started yelling out," Mr Garland told the Herald.

Mr Cleverley's ordeal started when he got off his bike to open a gate and the vehicle rolled towards him.

As he tried to stop it, he was knocked into a deep ditch, with the bike toppling on to him.

He climbed out from under the bike and out of the ditch, but because of his injuries he fell down a second bank and stopped just before he went into the river.

"He was a couple of inches away, it's lucky he stopped," said Mr Garland.

"He's a diabetic, and I thought he'd collapsed because of that. I was more worried about that and when I first saw him I probably thought the worst. I didn't think he'd had an accident on his 4-wheeler.

"He was in a bit of pain and he was thirsty. I told him he'd just spent the night right by a river and there was plenty of water there ..."

Mr Cleverley was treated at the scene by St John Ambulance paramedics before being airlifted to Waikato Hospital by the Bay of Plenty TrustPower TECT Rescue Helicopter. He was in a serious condition last night in the hospital's High Dependancy Unit.

The owner of the farm where he lives had spoken with Mr Cleverley's Nelson-based father. She had been told he had a crushed pelvis with multiple breaks.

"From what his father is saying, he's looking at a six to eight-week recovery in hospital.

"They can't operate and he can't be put in a cast. It's going to be a very painful recovery."

Mr Cleverley had been living in Matamata for about 18 months, after returning from a stint living in Australia.

Mr Garland said he could not work out how the accident happened.

"It's not very steep where he was at all. The bike's gone down the culvert and he's been thrown ... then he's climbed back up the bank and somehow, he's ended up down by the river and that's where he's spent the night."

The accident follows a spate of quad-bike crashes over the Christmas holiday period, including two where people were killed.

The spike in quad-bike incidents has led to renewed calls for better safety around bike use.

Last week the Ministry of Business, Innovation and Employment said farmers needed to make quad-bike safety a priority, but Federated Farmers hit back saying it was recreational users, not farmers, who were not getting the safety messages.