So I punched him on the shoulder, and he punched me on the arm, and we both laughed. We gazed down at the roaring Waimoana. ‘Wonder if that was how the river at Tangiwai looked that time?’ I said. ‘The Whangaehu?’

Tipene nodded, and we both stood silent for a bit. A black tree-trunk showed for a second in the racing current, then vanished. No, not a tree-trunk: a dead cow. Dad had been telling Grandad Duncan on the phone this morning how the creeks and rivers were getting higher every hour. Some sheep and cattle had been swept away. I wouldn’t want to be in the river today.

The rain had started again, although the sky looked a bit lighter in the west: dark grey instead of black grey. We turned to head back towards the house.

My Uncle Angus was killed four years ago. ‘Little Angus’ Mum called him, even though he was a tall, strong guy. ‘Big Angus’ was my great-great-great-grandad; he’s buried up in the cemetery, with lots of my other rellies.

My uncle was on the night express train heading to Auckland, on Christmas Eve 1953. He’d met a woman in Auckland while he was studying up there (he wanted to be a soil scientist, and help farmers grow more without harming the land), and they were planning to get married. He’d been down to visit my parents and grandparents, show them her photo, tell them all about her.

It was late at night, and his train was passing near Mount Ruapehu. What nobody knew was that the crater lake on the mountain had filled with so much water that the crater walls couldn’t hold it back any longer.

About an hour before the express train was due to pass, the crater collapsed, and a huge torrent of water, ice and boulders went hurtling down the side of Ruapehu and into the Whangaehu River. It tore downstream ‘like a battering ram’, the papers said, and smashed into the bridge where road and railway crossed. The bridge broke apart and was swept away.

A man driving north reached the bridge, saw the thundering river, and realised what had happened. At the same moment, he glimpsed the train’s headlight as it sped towards the bridge. He sprinted for the railway line, waving his torch. The driver must have seen something, because he slammed on his brakes. But the express couldn’t stop in time, and the engine, plus half a dozen carriages crashed down into the water.

Over 150 people died, and my uncle was one of them. Some survivors saw him dragging people through the carriages’ broken windows, pushing them towards the bank. Then one carriage flipped over, and a wall of water swept him away. They found his body the next day, half a mile downstream. He’s buried in our cemetery, too.