Manawatu River - Physical Environment

Physical Environment

The river is unique among New Zealand rivers, starting on the east side of the main dividing range and having its outflow to the west. The explanation for this is the uplift of the central ranges. The ranges moved upwards at the same time as the gorge was eroded by the river, instead of the more usual erosion of an already existing range. This suggests that the river is an old one, as it must have existed before the Ruahine and Tararua Ranges.

Major tributaries of the river include the Makakahi, Mangahao, Pohangina and Oroua Rivers. The Manawatu's total length is 180 km, making it only the 12th-longest in the country, but at 102 m³/s it is one of the country's greatest rivers in terms of flow, and second only to the Waikato River among North Island rivers.

The Manawatu River flooded in February 2004, displacing over 2000 people (primarily from Marton and Feilding) and damaging over 1000 Manawatu farms. The cost of the flood in terms of insurance payouts was NZ$122 million. Further damage was prevented by the opening of the Moutoa floodgates, which intercept the river between Foxton and Shannon.