The 3 MW Arnold Power Station was commissioned in 1932. Due to high rainfall in the region, the “run of the river” Arnold Scheme is able to generate at high capacity all year without any need to control the level of Lake Brunner which feeds it. A dam across the Arnold River provides the increase in water levels required for the station’s turbines.

The Arnold Station has an installed capacity of 3 MW and an average annual output of 25 GWh.

The scheme provides an excellent recreational fishery upstream of the dam, as well as recreational camping and walking areas. A combination of generation flow, flow over the spillway gates and residual flow past the Arnold Dam ensures the continued stability of the downstream fishery and availability of the river for kayaking.

An ongoing annual elver trap and transfer programme has been implemented at the Arnold Dam, to focus on improving (in particular) the indigenous long finned eel numbers that are declining throughout the country.

Plans to construct a dam in the valley behind the Dobson Township were abandoned when it became clear the land would not be released from the conservation estate. However plans for a smaller scheme with smaller storage areas and an output of 46 MW were developed, and consent applications were subsequently publicly notified. Hearings for this project were held in early 2008 with the decision being expected in the last quarter of 2008.