The Poutu Canal supplies water taken from the Tongariro River across to Lake Rotoaira, which then feeds the turbines of the Tokaanu Powerstation, so it is an important part of the Tongariro Power Scheme.
The flow varies in the canal, but when the water level is high, it can be quite ferocious and very fast flowing. The canal can also be emptied entirely when maintenance work needs to be carried out.
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