The Wairahi River is a river of New Zealand's Great Barrier Island. It is the only river (so named) on the island — the island's other watercourses all having names ending is "stream". The Wairahi flows generally west, roughly paralleling the island's long southwestern shore, from its origins north of Whangaparapara Harbour. A walking track from Whangaparapara to Port Fitzroy follows the river for part of its length.

• List of rivers of New Zealand

"Place name detail: Wairahi River". New Zealand Gazetteer. New Zealand Geographic Board. Retrieved 12 July 2009.