Mangapu River

The Mangapu River is a river of the Waikato region of New Zealand's North Island. It has its sources in numerous streams which flow generally northwards from the King Country south of Te Kūiti, the longest of which is the Mangaokewa Stream. These streams join to form the Mangapu close to Te Kuiti, and from here the river flows north, passing close to the east of Waitomo Caves, where the Mangapu caves have the largest entrance in the North Island (about 100 m (330 ft) long and 90 m (300 ft) deep), before flowing into the Waipā River at Ōtorohanga.

The New Zealand Ministry for Culture and Heritage gives a translation of "double stream" for Mangapū.

SH3 crosses the river on a 111 m (364 ft) bridge near Ōtorohanga built in 1966 and near Hangatiki on a 41 m (135 ft) concrete bridge built in 1977. The railway follows the east bank for about 6 km (3.7 mi), crossing only small tributaries, though it did suffer from flooding, for example in 1905.

The river at Ōtorohanga is classed as being in the worst 25% of similar sites as regards all measured pollutants, though some attempts are being made at restoration.