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Ric Georgeson sees much more than a waterway as he casts his eye over the mighty Rakaia River.
Framed by the soaring tree-lined stone walls of the Rakaia Gorge, this icy blue flow of water from the Southern Alps to the Canterbury coastline is his livelihood, and one of the great passions in his life.
"It's a dynamic, living thing. It's an exciting force in my life. I love it," he says.
"The river is constantly changing. With every flood it's like boating on a new section of river. It makes the river quite an exciting playground."
When Mr Georgeson is not powering through the river in his jet boat for thrill-seeking passengers, or guiding fishermen to the best spots, he is likely to be out on the water for himself.
"A friend of mine will come round and we'll just put a couple of beers in, and a bit of dinner, and we'll go up and fish till dark. If you spend the time, you will catch a fish."
The Rakaia River was formerly known as O Rakaia, meaning "the place where people were ranged in rank".
It was a traditional mahinga kai (place where food is grown/cultivated) for the people of Ngai Tuahuriri, of Kaiapoi, just north of Christchurch. Earth ovens for cooking moa have been found near the river mouth.
Sourced primarily from the Lyell and Ramsay glaciers of the Southern Alps 150km from the east coast, the river flows from two unnamed alpine lakes down the mountainous country.
"The source of the river is a totally different colour. You wouldn't recognise the Rakaia River's blue from the origins. The origins are sort of like a muddy grey," Mr Georgeson says.
"The alpine lakes fall out of the mountains in a very steep little river flow."
In the summer the river is fed by melted snow from the mountains, but in winter as the glaciers freeze up, part of the river near the main divides dries up and the high country lakes become its source.
High country farmer Ben Todhunter often looks out over the river as he tends to his stock, and like many riverside dwellers, has plenty of stories to tell about it.
"I love sitting up here, looking up the river. It's a nice place to sit and contemplate life."
Smaller rivers such as the Matthias, the Wilberforce and the Acheron from the north, as well as Lakes Coleridge, Heron and Lyndon, all feed into the Rakaia River as it winds down from the high country.
Heavy rains may cause the river to flood several times each year. The last time was in mid-November when the river reached 5000 cubic metres per second. The average river flow is 160 cubic metres per second.
"That really does change the lay of the whole river. The river moves millions of tonnes of debris. The river may form a number of different channels, a number of different shingle bars, pools [and] eddies can change direction," Mr Georgeson says.
"Through the braided river sections you may get as many as seven or eight different streams, and seldom do they ever meet."
Although known for being one of the great fishing rivers, this image has declined in the past few years due to over-fishing and changes in climate and ocean currents. One salmon farm near the gorge is releasing 100,000 fish each year to boost the stocks.
Rainbow and brown trout are the fishermen's target. Mr Georgeson's boasts of catching a 32lb salmon "that took me an hour and five minutes to land".
The diverse birdlife near the river adds to the community. Gulls, ducks, oyster catchers and the odd albatross are among many species of bird adding a special character to the river.
From the high country, the river flows down through the 7km-long canyon known as the Rakaia Gorge. Here the river forms into a singular flow, as it passes the popular skiing destination of Mount Hutt.
Maori legend has it that the gorge was formed in a titanic struggle between a taniwha living in the river and a northwest demon that came down from the mountains.
According to the legend, the demon came down and flattened the taniwha's property, and in response the taniwha brought down huge stones and boulders to block and imprison the demon, giving birth to the gorge.
Joiner Robert Lavery lives with his wife Jane and son Joseph in the Rakaia Gorge and admits he was not a river person when he first arrived there 10 years ago.
"I took me a long time because I wasn't a fisherman, and didn't go boating or anything. But you become a special breed. The river is important to people. You worry about things like didymo [an invasive weed] and people abusing the river."
As the river emerges from the gorge it spreads out again into a series of braided channels stretching across the shingle bed.
From here it meanders through the expanses of the Canterbury Plains, passing farms and tiny settlements, and the small township of Rakaia, next to State Highway One, which celebrated its 150th anniversary in November.
At Rakaia, the river is crossed by the country's longest road and rail bridges, each of which is 1750 metres long.
The final part of the river's journey is through more farmland before it meets the Pacific Ocean 50km south of Christchurch.
The tiny Rakaia Huts, next to the mouth of the river, is where Clarke Wilkes, 66, and partner Pam Williamson found their piece of paradise in semi-retirement.
"This is why we live here," Mr Wilkes says, looking out his second-floor lounge window to the neighbouring spring-fed lagoon where the Rakaia River and sea meet.
Aside from two days a week in Christchurch working as a hairdresser, Mr Wilkes will be out boating, fishing or on the quad bikes with his partner.
"Where else can you catch whitebait, trout, eels, flounder, mullet, salmon - all off your front lawn? Possibly this is the last of the untampered waters or areas to live."
Floodwaters often spilled in their yards, but "you don't worry about it".
As long as Mr Wilkes remains where he is, with his spot near the river, he will be happy.
"We have to keep to keep it the way it was. We don't try to spoil it."
