The Rakaia River is one of New Zealand’s largest braided rivers, and is highly valued for recreational (e.g. salmon fishing, jet boating and kayaking), aesthetic and ecological values. The river is fed from the Southern Alps and travels 150 kilometers in a easterly/southeasterly direction before entering the Pacific Ocean 50 kilometers south of Christchurch.
For much of its journey, the river is a braided river, characterised by wide shingle beds, numerous snaking channels and highly variable water flows. Braided rivers are formed when sediment and gravel build up on the riverbed. Eventually the build-up becomes so high that the water, seeking the lowest path, begins to flow down a new channel. In this way the streams of a braided river are constantly moving across their wide bed.
Close to Methven / Mount Hutt the river is briefly confined to a narrow canyon known as the Rakaia Gorge. Here, Discovery Jet operate exhilarating and breathtaking jet boat rides up the river and provide a water taxi service for the Rakaia Gorge Walkway which traverses the edge of the river.
State Highway One and the South Island’s Main Trunk Railway cross the river using separate bridges approximately 20 kilometres from the river mouth. These two bridges are New Zealand’s longest road and rail bridges respectively, approximately 1750 metres long.
The Rakaia River is home to one of the best salmon fisheries in New Zealand with good runs from November to March each season. The Rakaia also supports very good populations of sea-run trout in the lower reaches, and river resident trout in the middle and upper reaches.
The river also supports breeding colonies of the endangered black-billed gull, and is also known for its large wrybill population. Other important bird species using the riverbed are black-fronted tern and banded dotterel.