The Kokatahi River is a demanding whitewater run located on New Zealand's West Coast, draining the Southern Alps near Hokitika on the South Island. The run is typically accessed by helicopter, with Kokatahi Helicopters (03 755-7912) being one of the operators used to reach the put-in. The helicopter approach is not merely a convenience — the remote terrain makes it the standard method of access for most paddlers. The take-out is reached via the Hokitika River on Kaniere-Kowhitrangi Road, turning onto Upper Kokatahi Road after approximately 14 kilometres.

The river offers roughly 12 to 16 kilometres of continuous whitewater rated Class 4/5, with the run typically completed in a single day. The character of the river is relentless — paddlers describe it as unrelenting from top to bottom, featuring committing gorges, mandatory portages, and a high concentration of technical moves throughout. There is little opportunity for recovery between rapids, and the gorge sections add a serious commitment factor to the run. It is considered one of the premier expert whitewater runs on the West Coast and appears consistently on lists of must-paddle rivers in the region.

The scenery is a notable feature of the run, with spectacular gorge sections set against the backdrop of the Southern Alps. The river has also been paddled by packrafters, indicating it sees a range of craft, though the difficulty level means it is suited only to experienced whitewater paddlers regardless of craft type.

The West Coast of New Zealand's South Island is known for high rainfall, which keeps rivers running but also means flows can vary significantly. Helicopter costs for accessing the Kokatahi have been quoted at around NZD $150 per person, though rates may have changed. Shuttle services are also available through operators such as Alpine Adventures. The average cost of a shuttle on West Coast rivers generally runs between NZD $150 and $250. Sandflies are a noted nuisance in the surrounding bush and farmland areas, particularly during access hikes.