151km. I dug this answer in 20 seconds.
Waimakariri River
The Waimakariri River rises in the mountains near Arthur's Pass, and enters the sea near Christchurch.
It is the Waimakariri
Waimakariri United was created in 2008.
A braided river is one of a number of channel types and has a channel that consists of a network of small channels separated by small and often temporary islands called braid bars. Example: Waimakariri River-New Zealand..
The Waikato River, in the North Island, which is the longest river in New Zealand. 'Wai' meaning 'Water' is a very common prefix in the name of New Zealand rivers. There is also: Waiau, waikouaiti, Waitaki, Waimakariri, Wairau, Waipa, Waianakarua, Waikaia, Waipori, Wairoa, waitahanui, Waitara, Waitati, waitotora, Waihou. (and many others).
A river can be as long as a country! For example the Mississippi River is almost as long as the U.S vertically.
Rangiora, located in New Zealand's Canterbury region, is approximately 30 meters above sea level. Its elevation allows for a relatively flat landscape, typical of the area. The town is situated near the Waimakariri River and is known for its agricultural surroundings.
The river Alt is 28kilometers long.
The Charles River is about 81mi long.
The Missouri River is 2,341 miles long and is the longest tributary to the Mississippi River.
The River Wharfe is a river in Yorkshire, England and is 60 miles long.